FitSugar

Foods That Rob Your Bones

FitSugar — Tue, 19 Aug 2008 13:00:00 -0700

Some food combinations create nutritional synergy, like plums increasing iron absorption. On the other side of the spectrum are food pairings that block absorption of vitamins and minerals. Calcium, a vital mineral for bone health, can be negatively affected by seemingly innocent foods. Two types of chemicals, oxalates and phytates, bind to the calcium and block your bodies ability to absorb the mineral.

Oxalates are found in spinach and rhubarb and phytates are found in bran and beans. Cheese sprinkled on a spinach salad should not be factored into your daily total of calcium consumption. Same goes for milk you eat over your bran cereal.

Since eating calcium is better absorbed by your body than a calcium supplement, make sure you're not undermining your efforts by combining the mineral with an unwanted chemical.

Source

Vitamins

FitSugar — Wed, 08 Oct 2008 17:35:00 -0700

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Cancer

Growing evidence suggests that vitamins and micronutrients, especially from foods, may play important roles in the prevention or treatment of certain cancers:

One study found that the risk of prostate cancer risk dropped as consumption of vegetables high in vitamin C, such as broccoli and bell peppers, rose.
A diet high in cruciferous vegetables has been found to reduce the risk of kidney cancer; low consumption of cruciferous vegetables increases the risk.

On the other hand, high amounts of folic acid (a B vitamin) may be associated with colorectal cancer, and beta-carotene supplements are associated with increased lung cancer risk in smokers and people exposed to asbestos.

Macular Degeneration

In 2007, the National Eye Institute recommended that people with intermediate or advanced macular degeneration in one eye take a vitamin formula shown to reduce the risk of macular degeneration in the other eye by 25%. The formula contains vitamin C, vitamin E, beta-carotene, and zinc.

Osteoporosis

Vitamin K is widely used in Japan to treat osteoporosis, and studies suggest it also may be effective in treating rheumatoid arthritis.

Heart Disease

Although people with high levels of homocysteine are prone to developing blood clots in their arteries and veins, a 2007 study found that lowering homocysteine with B vitamins and folic acid does not reduce the incidence of deep vein thrombosis (DVT). A 2007 trial in adults with stable coronary artery disease found that lowering homocysteine levels 33% with folic acid and other B vitamins had no effect on arterial inflammation, meaning that lower levels were unlikely to offer protection against heart attack or stroke.

Introduction

Vitamins do not share a common chemistry, but they do share certain characteristics. They are all organic nutrients that are necessary in small amounts for normal metabolism and good health. Your diet or supplements provide most vitamins. The body can manufacture only three vitamins (D, K, and the B vitamin biotin) from nondietary sources. Unlike carbohydrates, fats, and proteins, vitamins are not sources of energy. Instead, vitamins are chemical partners for the enzymes involved in the body's metabolism, cell production, tissue repair, and other vital processes.

Vitamins are either fat soluble or water soluble. The fat-soluble vitamins, which include A, D, E, and K, are absorbed by the body using processes that closely parallel the absorption of fat. They are stored in the liver and used up by the body very slowly. The water-soluble vitamins include C and the B complex vitamins. The body uses these vitamins very quickly. Excess amounts are eliminated in urine.

The Recommended Daily Allowance (RDA) for vitamins, set by the Food and Nutrition Board of the National Academy of Sciences-National Research Council, has been used for years as a guide for determining the amount of vitamins needed for a healthy diet. The RDA refers to an estimate of the average daily requirement. It is not completely adequate, however, for informing people about the amounts of vitamins they may need.

The RDA is gradually being enhanced using a new standard called the Dietary Reference Intake (DRI). The DRI is based on the following ratings, which will eventually appear on labels:

The recommended daily allowance (RDA). This is the current rating on most vitamins.
The estimated average requirement (EAR). This is the amount adequate for 50% of all people, which will be put on labels when it can be calculated.
Adequate intake (AI). This is an amount that will be used if there is insufficient data to calculate the EAR.
Tolerable upper intake level (UL). This is the maximum dose likely to be safe in nearly all individuals. It will be included on labels if this amount is known.

Food and supplement labels now typically list the Daily Value (DV). This is the percentage of the amount of a nutrient that experts believe a person needs in their daily diet. On food labels it is usually based on one serving size for a person who takes in 2,000 calories a day.

Regulation of dietary supplements by the U.S. Food and Drug Administration (FDA) is a complex issue.

Labels on vitamins and other dietary supplements now include nutrient information and list all ingredients, including identifying parts of plants from which ingredients may be taken. Unlike the labels for drugs, however, labels for vitamins and supplements may not claim to prevent or treat any specific disease. Labels for vitamins and supplements include one of the following:

Health claim -- description of how the substance may reduce the risk of a health-related condition
Nutrient claim -- description of the amount of the nutrient in the product or
Structure or function claim -- description of how the product may affect organs or systems of the body, without claiming to prevent or treat specific disease

The quality of dietary supplements depends on the manufacturer and is not ensured by FDA. The U.S. government does not require that supplements be standardized, meaning that the amounts or quality of nutrients may vary depending on the batch. So, more expensive supplements are not necessarily better than the less expensive ones. Government regulations are in the process of catching up to the boom in the supplement industry. In the meantime, some companies voluntarily adhere to rigorous quality controls, while others do not.

The U.S. Pharmacopeia (USP), an independent organization that sets quality standards for drugs, has also implemented standards for vitamins. Consumers may look for the USP label on products of companies that adhere to these standards. USP verification means the following:

What is in the bottle matches what is listed on the label.
There are no harmful levels of contaminants.
The supplement will be absorbed properly into the body.
It has been produced according to good manufacturing standards.

Before selling any supplement introduced after 1994, manufacturers must submit information as to why the product is considered safe for people. The FDA may refuse to allow it on the market if it finds the evidence insufficient. The FDA does not require manufacturers to provide any scientific evidence that dietary supplements are safe and effective before a product is sold (unlike drugs, which must be proven both safe and effective through clinical trials). If a supplement causes side effects in people once it is for sale, the government may place restrictions on the supplement or withdraw it from the market. The FDA may also withdraw products from the market if their labels are misleading or false.

About 30% of Americans take at least one vitamin or mineral supplement daily. In a large study that examined the death rates of 11,000 people, however, there was no difference in mortality rate between those who took vitamin supplements and those who didn't. Most people who have a healthy diet do not need vitamins, but there are some exceptions.

Pregnant and Breast-Feeding Women. Women who are pregnant or who are breast-feeding generally need additional vitamins. Vitamins B6, B12, and folic acid are particularly important. Women who are vegetarians must be sure to avoid deficiencies, which can harm their offspring. Folic acid reduces the risk for neural tube defects and possibly facial abnormalities, such as cleft palate. Studies also show that low folate levels during pregnancy are associated with low birth weight, a risk factor for the development of cardiovascular disease in adulthood. Multivitamins that contain folic acid also appear to be somewhat protective. A woman's best approach is to take extra folic acid plus multivitamin supplements (which have additional benefits), starting them before becomming pregnant.

The human body stores several years' worth of vitamin B12, so nutritional deficiency of this vitamin is extremely rare. Although, people who follow a strict vegetarian diet and do not consume eggs or dairy products may require vitamin B12 supplements.

Pregnant women with healthy diets may have low folate levels and need to take supplements. Requirements are as follows:

The recommended daily allowance (RDA) for folic acid prior to conception and during pregnancy is 400 mcg.
During breast-feeding 260 - 280 mcg is recommended.

The following vitamins may have some value for pregnant women:

Choline, another vitamin B, is also essential for pregnant (450 mg) and nursing women (550 mg). Choline plays a key role in brain development. Not getting enough during pregnancy can lead to memory and cognitive defects in the baby. Choline supplements can also lessen the cognitive defects of prenatal alcohol exposure.
Vitamin B6 may help improve morning sickness.
Vitamin C may reduce the risk of urinary tract infections during pregnancy.
Vitamin D may help prevent preeclampsia.
One study also suggested that if pregnant women took vitamin K supplements, their infants might not need the required injection of this vitamin after birth, but supplements of vitamin K during pregnancy are not currently recommended.

Some women have low vitamin A reserves in their liver. It is important to note, however, that too much vitamin A significantly increases the risk for birth defects. Daily amounts of 10,000 IU (international units) of vitamin A in supplements and food (an amount not far above the RDA level) can pose a danger. Experts recommend that pregnant women take in no more than 8,000 IU per day and avoid eating liver.

Infants and Children. Infants who are breast-fed by healthy mothers receive enough vitamins except, in some cases, vitamins K and D. Human milk has low levels of K, and the newborn's immature intestinal tract may not produce enough of the baby's own supply. Most babies are given an injection of this vitamin at birth. Infants being breast-fed by malnourished women or those who lack sufficient exposure to sunlight may be deficient in vitamin D. In these cases, supplements of 200 - 300 IU are recommended. Formulas are required to contain sufficient vitamins and minerals. One study suggests that vitamin supplements for infants under 1 year of age may help protect them from developing type 1 diabetes later on. Beyond infancy, most American children receive all the vitamins they need from their diet unless they are living in severely deprived circumstances.

Smokers. Smoking interferes with absorption of several vitamins, importantly vitamins C and D. In one study nearly 25% of female smokers and 31% of male smokers were deficient in vitamin C. Smoking can interfere with the metabolims of vitamin D, resulting in poor muscle function. Taking high doses of antioxidant vitamins, however, may actually be harmful in smokers, especially beta carotene. Instead of taking supplements, most smokers should be sure their diets are rich in fresh fruits and vegetables and whole grains. Of course, smoking cessation is the most important intervention of all.

Click the icon to see an image of sources for vitamin C.

Alcoholics. Alcoholics often suffer from multiple vitamin deficiencies. The most dangerous deficiencies are from vitamins B1 (thiamin), folic acid, B6 (pyridoxine), B2 (riboflavin), and vitamin C. Low levels of B6 are associated with increased risk of colorectal cancer in men who drink large amounts of alcohol.

Overweight Adults. Overweight and obesity causes many problems that often result in metabolic syndrome or type 2 diabetes. Evidence suggests that isoflavones can help regulate cholesterol levels and reduce body weight and fat mass. Because some medications used to control blood sugar levels reduce folic acid and vitamin B12, some people may need vitamin supplements.

People Who Have Had Gastric Bypass Surgery. Vitamin deficiency is a recognized complication of gastric bypass surgery. Women, African-Americans of both sexes, and adults who have had laparoscopic Roux-en-Y bypass surgery are at highest risk. The deficiency is treated with water-soluble vitamin supplements.

Strict Vegetarians. Strict vegetarians need supplements of vitamin B12, unless they get enough of it from fortified cereals and other grain products.

Dieters and Vegetarians. People on weight-reduction diets with less than 1,000 calories a day should probably take a multivitamin and should also check regularly with a physician.

Vegetarians may need riboflavin, vitamin B12, and vitamin D supplements. Vegans, who do not eat dairy or eggs as well as meat, may be at further risk for vitamin A deficiencies if they do not also have plenty of dark colored fruits and vegetables. Those who eat eggs and dairy products need only watch their iron levels.

Deficiencies in vegetarian children may be particularly harmful. (One study, for example, reported that adolescents who had been on macrobiotic diets before age 6 and were deficient in vitamin B12 scored lower on psychological tests.) Pregnant and breast-feeding women who are vegetarians must be sure to have sufficient vitamins. Of special note, maternal deficiencies in vitamin B12 may cause delayed growth and neurologic problems in their newborns.

Click the icon to see an image of sources for vitamin D.

Older Adults. Deficiencies of vitamins and important minerals have been observed in almost a third of elderly people. Often their dietary habits slip and they fail to eat balanced meals regularly. Multiple drug regimens may prevent absorption of some vitamins. Elderly people, particularly if they are not exposed to sunlight, may be deficient in vitamin D. They also may have low levels of important B vitamins. (Older adults showing signs of dementia should be checked for B12 deficiencies as well as other disorders causing mental disturbances.) One study reported that the immune systems of elderly people may benefit from higher levels of vitamin E than the daily recommended dosage. It should be noted, however, that metabolism slows down as a person ages, and in elderly people it takes the liver longer to eliminate drugs and vitamins from the body. The effect of some vitamin supplements, therefore, may be intensified. Dosage levels of vitamin A, for instance, which might be harmless in a younger adult, could be toxic in an elderly patient. Nevertheless, experts are increasingly recommending extra vitamin and mineral supplements for older people.

People Who Need to Avoid Sunlight. People who need to avoid sunlight or are housebound, and whose diet is low in foods that contain vitamin D should take supplements. People with darker skin are at higher risk for deficiencies than those with whiter skin. (Note: vitamin D is toxic in high doses, and no one should exceed the recommended daily intake of vitamin D except under the direction of a physician.)


Benefits	Essential for growth, bone development, night vision, reproduction, and healthy skin.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	Vitamin A RDA and Upper Limit (when toxicity is risk) are the following: For children: 1,000 IU ages one to three (upper limit is 2,000 IU); 1,333 IU ages 4 - 8 (upper limit is 3,000 IU); and 2,000 IU for 9 - 13 (upper limit is 5,665 IU). For nonpregnant women: 2,330 IU ages 14 through adulthood. (Upper limit is 9,335 IU for ages 14 - 18 and 10,000 IU for women over 19.) For pregnant women: 2,500 IU for pregnant women under 18; 2,565 IU for pregnant women over 19. (Upper limit is 9,335 IU for ages 14 - 18 and 10,000 IU for women over 19. It should be noted that some experts recommend 8,000 IU as the upper limit during pregnancy.) Warning: Use of the topical acne medication tretinoin, a vitamin A derivative, during pregnancy can cause birth defects. For nursing women: 4,000 IU for nursing mothers under 18; 4,335 IU for nursing mothers over 19. (Upper limit is 9,335 IU for ages 14 - 18 and 10,000 IU for women over 19.) For men: 3,000 IU ages 14 - 18; 3,000 IU for ages 19 and above. (Upper limit is 10,000 IU.) Note: In determining the daily vitamin A allowance, experts also take note of provitamins, such beta carotene, that convert to vitamin A. Some experts recommend 3 - 6 mg of beta-carotene. Vitamin A is also now being measured with a new unit called the Retinol Activity Equivalent (RAE or RE). One RE is equal to 1 mcg. Retinol is the most active form of vitamin A and it is also converted in the liver from carotenoids. One RE is equal to 12 mcg of beta-carotene or 24 mcg of alpha-carotene or beta-cryptoxanthin).
Foods containing the vitamin	Animal products, such as liver, dairy products, eggs, and fish liver oil. Provitamin A carotenoids are also found in dark red, green, and yellow vegetables and fruits. Requires some dietary fat to be absorbed.
Effects of deficiencies	Skin disorders, severe diarrhea, and eye damage. In less developed countries severe deficiencies cause blindness in 250,000 children each year. Diets low in vitamin A may also increase the risk of developing cancer. Low dietary intake of vitamin A has been associated with impaired lung function in children.
People at risk for deficiencies	Preschool children and any child with inadequate intake of protein, calories, and zinc. Iron deficiency may also impair metabolism of vitamin A. People with asthma. People with serious disorders in the intestine, liver or pancreas, such as cystic fibrosis, steatorrhea, biliary obstruction, inflammatory bowel disease, cirrhosis, and others. People who have undergone Roux-en-Y gastric bypass surgery. Vegans (vegetarians who do not eat eggs and dairy). Such individuals should be sure to have plenty of deep-colored fruits and vegetables. People who abuse alcohol. It should be noted, however, that people with alcoholism may be at risk for vitamin A deficiency, but a combination of high-dose vitamin A and alcohol may cause toxic effects in the liver. Healthy adults usually have a year's store of vitamin A in the liver, so temporary nutritional deficiencies or problems with fat absorption are unlikely to cause serious vitamin A deficiency problems.
Toxicities	Very toxic when taken in high-dose supplements for long periods of time. Symptoms of overdose include dizziness, nausea, vomiting, headache, skin damage, mental disturbances, and, in women, infrequent periods. Can affect almost every part of the body, including eyes, bones, blood, skin, central nervous system, liver, and genital and urinary tracts. Severe toxicity can cause blindness and may even be life threatening. In children, chronic overdose can cause fluid on the brain and as well as adult complications. High consumption of vitamin A may also increase the risk of gastric cancer and the risk of osteoporosis and fractures in both men and women. Pregnant women who take amounts not much higher than RDA levels increase the risk for birth defects in their children. Liver damage can occur in children who take RDA-approved adult levels over prolonged periods of time or in adults who take as little as five times the RDA-approved amount for 7 - 10 years.


	B Vitamins: General Information	Vitamin B1 (thiamin)
Benefits	The B vitamins have a wide and varied range of functions in the human body. Most B vitamins are involved in the process of converting blood sugar into energy.	Essential for converting blood sugar into energy and is involved in metabolic activities in nerves, heart, and muscles and in the production of red blood cells.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)		RDA is 1.2 mg per day for men and 1.1 mg for women.
Foods containing the vitamin		Best source is pork and good sources are dried fortified cereals, oatmeal, corn, nuts, cauliflower, and sunflower seeds. Supplements for people with normal diets and health are unnecessary.
Effects of deficiencies	Deficiencies are uncommon in the U.S., but when they occur, they usually involve several B vitamins, since many of them come from the same food groups.	Severe vitamin B1 deficiency is known as beriberi. It can cause visual disturbances, paralysis, staggering, loss of sensation in the legs and feet, psychosis, and congestive heart failure.
People at risk for deficiencies	Alcohol interferes with these vitamins, and some of the physical and mental problems that alcoholics experience may be attributed to a deficiency of B vitamins. Elderly people are also at risk for deficiencies because of inadequate diets and potential interference with B-vitamin absorption by medications. Deficiencies can occur in severely malnourished people or in those receiving long-term dialysis or intravenous feeding. Vegetarians may be at risk.	See general vitamin B description.
Toxicities	Because the B vitamins are water-soluble and eliminated in the urine, toxic reactions from oral administration of most of them are extremely rare. (Exceptions are niacin and B6.) It should be noted that substances known as B15 (pangamic acid) and B17 (laetrile) are neither vitamins nor nutrients; both chemicals are highly dangerous and have no proven nutritional or health value.	No toxic effects have been reported from thiamin.


	Vitamin B2 (riboflavin)	Vitamin B3 (niacin) also known as nicotinic acid	Vitamin B5 (Pantothenic Acid)
Benefits	Important in the production of energy.	Helps break down blood sugar for energy. Acts as a vasodilator, widening blood vessels and increasing blood flow. May be prescribed for improving cholesterol levels.	Important for metabolism of fats, carbohydrates, and proteins, as well as production of steroid hormones and other important chemicals.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	DRI is 1.7 mg.	DRI is 20 mg.	Adequate intake (AI) is 4 - 7 mg.
Foods containing the vitamin	Liver, dried fortified cereals, dairy products, fish. Some dark green vegetables. Supplements for people with normal diets and health are unnecessary.	Mackerel, swordfish, chicken, veal, dried fortified cereals, pork, salmon, and beef liver. Supplements are unnecessary in people with normal health and diets.	Whole grains, beans, milk, eggs, and liver. Supplements are unnecessary in people with normal health and diets.
Effects of deficiencies	Deficiencies affect the skin and mucous membranes and can cause cracks on the lips or corners of the mouth, eczema of the face and genitals, a burning sensation on the tongue, eye irritation. May contribute to anemia when iron levels are low and contribute to elevated levels of homocysteine, a heart risk factor.	Deficiency causes pellagra; symptoms can include eczema, intestinal and stomach distress, depression, headache, thinning of the hair, and excess saliva production.	Deficiency is unlikely except in company with other B vitamin deficiencies. Symptoms include abdominal distress, burning sensation in the heels, and sleep problems.
People at risk for deficiencies	See general vitamin B description.	Alcoholics and any malnourished persons.	Alcoholics and any malnourished persons.
Toxicities	Until recently, no toxic effects had been reported even from large doses of riboflavin. However, one study indicated that high consumption of vitamin B2 might increase the risk of stomach cancer. More research is needed. (In the same study, vitamins B1, B3, and B6 were protective.)	Even mildly high doses of niacin can cause hot flushing of the face and shoulders, headache, itchiness, and stomach problems. Some report heart disturbances and temporarily lowered blood pressure. Large doses may produce ulcers, gout, diabetes, and liver damage, which are usually reversed when high doses are discontinued.	Although no toxicity has been reported in humans, high dosages have caused liver damage in rats.


	Vitamin B6 (pyridoxine)	Vitamin B12 (cobalamin)
Benefits	Has an effect on over 60 proteins in the body, importantly, those that play a role in the nervous system, in red and white blood cell production, and in heart disease.	Essential for the production of blood cells, manufacturing genetic material, and for healthy functioning of the nervous system. New evidence suggests that high levels of B12 may protect against colon and rectal cancer.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	RDA is 1.3 mg in adults under 50 and 1.7 mg for older men and 1.5 for older women. (Some experts recommend 3 to 6 mg for people who need heart protection.) Upper limit is 100 mg for adults.	RDA is 2.4 mcg in men and nonpregnant women, 2.6 mcg in pregnant women, and 2.8 mcg in nursing mothers.
Foods containing the vitamin	Meats, oily fish, poultry, whole grains, dried fortified cereals, soybeans, avocados, baked potatoes with skins, watermelon, plantains, bananas, peanuts, and brewer's yeast.	The only natural dietary sources are animal products, including meats, dairy products, eggs, and fish (clams and oily fish are very high in B12). Like other B vitamins, however, B12 is added to commercial dried cereals.
Effects of deficiencies	Increased levels of homocysteine, associated with heart disease and possibly Alzheimer's disease. Skin problems and nervous system disorders, including impaired memory and concentration. Increased risk for kidney stones. One study found a correlation between vitamin B6 deficiency and inability to conceive or carry a child to term. In unborn children, some evidence shows that lack of vitamin B6, in addition to vitamin B12 and folic acid, may be responsible for defects such as cleft lip and palate and spina bifida. Supplementation with these vitamins is advised during pregnancy. Note: People who have been taking more than 50 mg for some time and stop suddenly are at risk for a so-called rebound deficiency. When people stop, they should taper off slowly.	Deficiencies elevate homocysteine, a possible risk factor for heart disease and Alzheimer's disease. Increased risk of bone fractures. Abnormal gaits in the elderly. May cause severe depression, memory loss, instability, disorientation, and decreased reflexes, and possibly hearing loss. Children who are deficient may experience growth failure. Deficiencies in pregnant and breast-feeding women may cause neurologic harm in their offspring. A genetic defect that causes vitamin B12 deficiencies is responsible for pernicious anemia, a serious disorder that causes rapid heart rate, shortness of breath, dizziness, weakness, and fatigue. It must be treated with injections of vitamin B12 or else neurologic damage may occur.
People at risk for deficiencies	Alcoholics and any malnourished person. In rare cases, infants are born unable to metabolize pyridoxine; in such cases, seizures or convulsions can occur and vitamin B6 must be administered.	Alcoholics and any malnourished persons. Evidence suggests deficiencies may be caused by Helicobacter pylori (H. pylori) bacteria (a cause of ulcers). Nearly 30% of patients with inflammatory bowel disease have vitamin B6 deficiency, as well as low levels of iron and vitamin D. People who take the antibiotic isoniazid, high blood pressure medication hydralazine, and the drug penicillimine are at risk for vitamin B6 deficiency. The elderly and people with Crohn’s disease and those who have undergone ileal and ileocolonic resection may have trouble absorbing natural vitamin B12 and require supplements. Some evidence shows that patients with Parkinson’s disease treated with levodopa plus dopa decarboxylase inhibitor (DDC-i) and catechol-O-methyltransferase inhibitor (COMT-i) have low levels of both vitamin B12 and folate. As a result, they need to take supplements of these vitamins. Other studies have found that patients with diabetes treated with metformin, but not roziglitazone, are at risk for low levels of vitamin B12. Vitamin B12 deficiency is also common in patients with polyneuropathy. In up to one-third of patients, vitamin B12 deficiency is the sole or major contributing cause of their neuropathy. Treatment with vitamin B12 has a high success rate in improving the symptoms. Vegetarians are at higher risk for deficiencies.
Toxicities	Very high doses can cause nerve damage with symptoms of instability and numbness in the feet and hands, which may be permanent in some cases. Of specific concern are possible adverse effects on nerve development in the offspring of pregnant women who take large doses, such as for morning sickness.	There is no evidence of toxicity with this vitamin.


	Biotin (a B vitamin)	Choline (a B vitamin)	Folate, or Folic Acid, its synthetic form (a B vitamin)
Benefits	Involved in the production of amino acid proteins and fatty acids.	Essential for fetal brain development and for learning and memory.	Important for many metabolic processes in the body. It is used in the manufacturing of neurotransmitters (chemical messengers in the brain), in protecting the heart, and for synthesizing genetic materials (DNA) in the cells. It may improve blood flow.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	There is no DRI for biotin; some experts suggest 30-100 mcg.	RDA 425 mg for nonpregnant women, 450 mg for pregnant women, and 550 mg for nursing women.	Supplements may be folate (natural) or folic acid (synthetic). Folic acid is nearly twice as potent as folate. DRI is 400 mcg (.4 mg) of folate for the general population, 600 mcg during pregnancy and 500 mcg while nursing. Women who are planning to be pregnant should certainly take 400 mcg of folic acid before conception, during pregnancy, and while nursing.
Foods containing the vitamin	Dietary sources are eggs, milk, liver, mushrooms, bananas, tomatoes, whole grains, nuts, and brewer's yeast. Also produced by bacteria in the intestines.	Peanuts, eggs, cauliflower, and meats, especially liver.	Avocado, bananas, orange juice, cold cereal, asparagus, green leafy vegetables, dried beans and peas, and yeast. Folic acid supplements are now added to commercial breads and cereals.
Effects of deficiencies	Deficiencies are almost unheard of.	Low levels during pregnancy increase risk of birth defects in newborns.	As with vitamins B6 and B12, deficiencies of folate elevate levels of homocysteine, an amino acid in the body that may increase the risk for heart disease, and possibly Alzheimer's disease. Folic acid supplements lower homocysteine levels, but with little or no impact on risk of atherosclerotic disease in the heart or in the peripheral arteries and veins. This suggests that homocysteine may be a marker of cardiovascular disease, rather than a cause. This being said, one 2007 study found that folic acid supplementation in patients with low folic acids levels substantially reduced the risk of a first stroke. Low levels during pregnancy increase risk of birth defects in newborns, and folic acid supplementation plays a key role in preventing birth defects. Folic acid deficiencies Deficiencies can also cause depression and megaloblastic anemia and impair concentration, memory, and hearing.
People at risk for deficiencies			Alcoholics, malnourished persons, people with conditions that disturb the small intestine, people taking certain drugs, particularly methotrexate. Other risk factors for deficiency: high-dose aspirin, smoking, treatment for seizures, taking oral contraceptives.
Toxicities		Excessive doses can cause intestinal problems, and there is also some concern that high doses can be carcinogenic.	Possible connection between high consumption of folate/folic acid and colorectal cancer now under exploration. Some link between high doses and central nervous system disorders, zinc deficiency, and seizures in epileptics. This risk appears to be low, but results indicate that megadoses should be avoided. High amounts in the elderly may mask symptoms of vitamin B12 deficiencies.


Benefits	Vitamin C is a water-soluble vitamin. Acts as an antioxidant (reduces harm from damaging chemical processes in the body). Essential for the production of collagen, the basic protein in bones, cartilage, tendons, and ligaments. A 2007 study found that vitamin C supplements can help prevent the development of complex regional pain syndrome following wrist fracture. Another study found that prostate cancer risk dropped as consumption of vegetables high in vitamin C, such as broccoli and bell peppers, rose. It may also protect against brochoconstriction during exercise in people with asthma. May help boost the immune system.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	DRI is 75 mg (women) and 90 mg (men). (Smokers need an additional 35 mg.)
Foods containing the vitamin	Citrus fruits and juices, papayas, hot chili peppers, bell peppers, broccoli, potatoes, dark leafy greens, kale, red cabbage, cauliflower, cantaloupe, sweet potatoes, and Brussels sprouts. Orange juice is the most important source of vitamin C in the U.S., with frozen juice being the best source of the vitamin.
Effects of deficiencies	Scurvy is the primary deficiency disease. Affects most body tissues, particularly bones, teeth, and blood vessels. Early symptoms include tiredness, weakness, irritability, weight loss, and vague muscle aches. Later symptoms are bleeding gums, wounds that won't heal, rough skin, and wasting away of the muscles. Deficiencies may contribute to periodontal disease and gallstones. Low dietary intake of vitamin C has been associated with impaired lung function in children. Low intake may also increase lead levels in the blood.
People at risk for deficiencies	Deficiency has been uncommon in the U.S., usually occurring in the elderly, alcoholics, cancer patients, and some people on severely limited diets low in fresh fruits and vegetables. Surprisingly, however, studies now suggest that as many as 16% of middle-aged Americans, with the highest risk in smokers and middle aged men, are deficient in vitamin C. High doses of aspirin taken over a long period of time can interfere with vitamin C.
Toxicities	Tolerable upper limit is 2000 mg/day. High doses may cause headaches and diarrhea. Long-term high doses may increase risk for kidney stones. Ascorbic acid increases iron absorption so people with blood disorders, such as hemochromatosis, thalassemia, or sideroblastic anemia, should avoid high doses. Large doses may also thin blood and interfere with anticoagulant medications, blood tests used in diabetes, and stool tests. Rebound scurvy can occur after abrupt withdrawal from long-term large doses. This may affect infants or pregnant women who withdraw suddenly from high doses.


Benefits	Vitamin D is actually a single term for several hormones that are stored mainly in the liver and also in fat and muscle tissue. It is essential for the absorption of calcium into the bone and for normal bone growth.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	RDA is 200 IU (5 mcg) per day for children and most adults to age 50, 400 IU (10 mcg) for people between ages 50 and 60, and 600 IU over age 70. and 1000 IU (15 mcg) for those over 70. People who are housebound, do not have sufficient exposure to sunlight, or are dark-skinned individuals, as well as breast-fed infants, should take need vitamin D supplements. The maximum tolerated dose after the age of 12 months is 2,000 IU/day
How the body gets the vitamin	There are two forms of vitamin D. Vitamin D3 is made in the body from a chemical reaction to the ultraviolet radiation in sunlight. Vitamin D2 is found in a few food sources, including vitamin D fortified milk, fatty fish, egg yolk, and liver.
Effects of deficiencies	Softening of the bones caused by low levels of calcium and phosphorous (called rickets in children and osteomalacia in adults). Also increases the risk for bone-related knee problems, and hip fractures in postmenopausal women. Associated with a higher risk for prostate cancer and breast cancer risk. Evidence suggests that vitamin D deficiency may be responsible for poor muscle strength after bone fracture. The deficiency is associated with high blood pressure and diabetes, but it is unknown whether supplementation with vitamin D impacts these diseases. Studies now suggest vitamin D plays a role in age-related macular degeneration (AMD), and that drinking milk with added vitamin D can help protect against AMD.
People at risk for deficiencies	Older people, particularly if they live in the North, who are underexposed to sunlight. Obesity may also increase risk. There is some concern, in fact, that vitamin D deficiency may be a growing problem in the US among younger adults as sunscreen use becomes widespread. Individuals at highest risk for vitamin D deficiency are those who assiduously avoid the midday sun, wear protective clothing, regularly use sunscreen, and have dark skin. Exposure to sunlight for about 15 - 20 minutes at mid-morning or mid-afternoon three times a week is recommended for most people who live in temperate climates.
Toxicities	Vitamin D is very toxic in high doses. In infants, daily amounts higher than 1,000 IU can cause mental and growth retardation, kidney failure, and death. In children and adults, daily amounts over 50,000 IU can cause weakness, anorexia, vomiting, diarrhea, and mental changes. Prolonged use of megadoses can cause calcification of soft tissue and life-threatening kidney failure. Low-calcium diets and withdrawal from the vitamin can usually reverse the side effects except for kidney failure.


	Vitamin E (Tocopherol or Tocotrienol)	Vitamin K
Benefits	A fat-soluble antioxidant vitamin that helps prevent cell membrane damage and may inhibit oxidation of LDL cholesterol (a process that increases its harmful effects on arteries). Researchers once thought that vitamin E might protect against cardiovascular disease. This theory has been debunked. However, a 2007 study found that vitamin E supplementation reduced the risk of deep vein thrombosis (DVT) in women at risk for, or with a history of, DVT. Vitamin E supplements have also been shown to produce a statistically significant decrease in menopausal hot flashes. There is also early evidence that vitamin E may protect against ovarian cancer.	The most important function of vitamin K is its role in blood clotting and prevention of bleeding. As a result, the vitamin may be able to help treat hepatoma, leukemia, and hepatocellular carcinoma, a form of liver cancer. The vitamin also contributes to maintaining healthy bones and healing fractures. Vitamin K is widely used in Japan to treat osteoporosis, and studies suggest it may be effective in treating rheumatoid arthritis.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	RDA is 15 mg (22 IU) for all adults, including pregnancy women. Nursing mothers need 19 mg (28 IU). (Supplements should be taken along with some oil or fat to be absorbed.) Vitamin E is composed of 8 compounds (four tocopherols and four tocotrienols). Vitamin E is most often available as supplements of dl alpha tocopherol (a synthetic form). Other vitamin E compounds may prove to be more active than the standard synthetic supplement. They include natural vitamin E, called d-alpha- or RRR-alpha-tocopherol succinate (VES). Other vitamin E compounds of interest are tocotrienol and beta and gamma tocopherol. Supplements that contain a combination of some of these forms may be most beneficial.	RDA is 60 - 65 micrograms (women) and 70 - 80 micrograms (men).
Foods containing the vitamin	Vegetable oils (particularly wheat germ oil), sweet potatoes, turnip greens, mangos, avocados, nuts, sunflower seeds, and soybeans. Tocotrienol (a possibly beneficial form) is found in natural tropical oils. Palm oil sold in the US is refined and does not contain tocotrienol.	Best dietary sources are canola oil, cruciferous vegetables, and soybean oil. Good sources are beef liver, bran, and olive oil. Also produced by bacteria in the intestines.
Effects of deficiencies	Deficiencies have not been established.	Easy bruising, bleeding. May increase the risk of hip fractures in women.
People at risk for deficiencies	Low-birth weight infants. People who eat a low-fat diet. People with medical problems that impair fat absorption, such as Crohn's disease, cystic fibrosis, steatorrhea, liver diseases (such as cirrhosis). People with abetalipoproteinemia, a rare genetic disorder that impairs fat metabolism.	Deficiency may occur in patients who have problems absorbing fats, such as those with cirrhosis, people who are on long-term antibiotic therapy, or who are taking other medications, including cholestyramine, Dilantin, and phenobarbital. Some evidence suggests that more young people may be deficient than previously believed.
Toxicities	Upper level recommended is 1,500 IU of alpha tocopherol. Large doses may cause bleeding problems, particularly in people taking anti-clotting medications. Some research now indicates that vitamin E, like other antioxidants, may have pro-oxidant and damaging effects. Although vitamin E is one of the best studied vitamins, research has yielded conflicting results, and definitive conclusions about the benefits and toxicity of vitamin E have not yet been determined. In a major 2005 study, there was no significant difference in cancer rates between people who took 400 IU of vitamin E daily and those who did not, although those who took the supplement had a higher risk of heart failure. Additional studies also link high levels of vitamin E with a slightly increased risk of heart failure and death. On the other hand, studies show that vitamin E may reduce heart problems in high-risk patients such as certain people with diabetes.	Allergic-type responses, including rash and itching, to high doses have been reported. Those who are taking Coumadin, an anticoagulant, should not take vitamin K without consulting a physician. Vitamin K deficiency can cause anorexia, lethargy, growth retardation, bone loss, soft tissue calcification, and death.

Carotenoids

Carotenoids are a group of more than 700 fat soluble nutrients that produce the colors in foods such as carrots, pumpkins, sweet potatoes, tomatoes, and other deep green, yellow, orange, and red fruits and vegetables. Many are proving to be very important for health. Beta carotene is the most widely studied carotenoid, but others are proving to be of great interest. As with some, but not all, carotenoids, beta carotene is known as a provitamin A because it converts to the vitamin in the body.

They are categorized as either xanthophylls or carotenes according to their chemical composition.

Carotenes are hydrocarbons and most are found in yellow, orange, and red vegetables. They include beta and alpha carotene and lycopene.

Beta Carotene and other Provitamin A Carotenoids. Beta carotene, alpha-carotene, and beta-cryptoxanthin are carotenes that are converted into vitamin A or retinol (the active form of vitamin A) in the body. They are found in many yellow fruits and vegetables. Beta carotene is the most widely studied carotenoid. Evidence now strongly suggests that when taken as a separate supplement it can have harmful effects.
Lycopene. Lycopene is responsible for the red color in fruits and vegetables, including tomatoes, red grapes, watermelon, and pink grapefruit. It is also found in papayas and apricots. It does not convert to vitamin A but may have important cancer fighting properties and other health benefits.
The beneficial actions of most carotenes such as those tomatoes, corn, and carrots, appear to be enhanced by cooking them, especially in oil (preferably olive, canola, or another monounsaturated oil). (Note: Cooking can also destroy certain nutrients, such as vitamin C, in these vegetables.)

Xanthophylls contain oxygen and most are found in green vegetables, such as broccoli, cabbage, and kale. They are also in yellow fruits and vegetables. Xanthophylls include lutein and zeaxanthin, which are both stored in the retina of the eye. Neither converts to vitamin A. Both are powerful antioxidants and may be very important for healthy eyes. Unlike carotenes, cooking may reduce the antioxidant activity of some xanthophylls in foods, although probably not to any significant degree.

Phytochemicals

The word phytochemicals means plant chemicals. Hundreds of phytochemicals are being studied. Many are believed to have a major positive impact on human health. Some contribute to the bright and vivid colors found in fruits and vegetables. The results of studies on specific phytochemicals are not necessarily applicable to the vegetables or fruits that harbor small concentrations of these chemicals.

Nevertheless, it is obvious that vegetables and fruits are healthful, which is probably due to some balance of phytochemicals, carotenoids, vitamins, fibers, and minerals rather than any single substance.

The benefits of individual phytochemical supplements are largely unproven. Furthermore, they are not regulated and high concentrations of some may behave like drugs and can be toxic and possibly even contribute to cancer cell growth.

Polyphenols are important phytochemicals, and flavonoids (or catechins) are members of the polyphenol family that may have significant health benefits. Laboratory studies have shown that specific flavonoids suppress tumor growth, interfere with sexual hormones, prevent blood clots, and have anti-inflammatory properties. In general, flavonoids are found in celery, cranberries, onions, kale, dark chocolate, broccoli, apples, cherries, berries, tea, red wine or purple grape juice, parsley, soybeans, tomatoes, eggplant, and thyme. Most common berries contain flavonoids and are particularly rich in potent antioxidants.

Among the important flavonoids are resveratrol, quercetin, and catechin. Evidence suggests that resveratrol (found in red wine, grapes, olive oil) may be extremely potent. In laboratory studies, it increases cell survival and has been shown to increase the life span of worms and fruit flies. Catechins are the primary flavonoids in tea and may be responsible for its possible beneficial effects. Flavonoids in dark chocolate may also be health protective.

Isoflavones, commonly known as phytoestrogens, have actions that are similar to the female hormone estrogen. A high consumption of soy, which is primarily composed of isoflavones, may reduce symptoms resulting from estrogen depletion during menopause. In a recent study, supplementation with isoflavones decreased hot flashes by 57% and night sweats by 43%, but other research is less favorable.

Lignan is another phytoestrogen and is found in the fiber layers of whole-grains, berries, some seeds, some vegetables, and a few fruits.

Isothiocyanates and related substances, indoles, are also known as mustard oils and are responsible for the sharp taste in cruciferous (also called brassica) vegetables. Such vegetables include broccoli, cabbage, Brussels sprouts, cauliflower, collards, kale, kohlrabi, mustard greens, rutabaga, turnips, and bok choy. Isothiocyanates also stimulate enzymes that convert estrogen to a more benign form and may block steroid hormones that promote breast and prostate cancers. (Cruciferous vegetables are also high in fiber, vitamin C, and selenium.)

Monoterpenes have two important phytochemicals, perillyl alcohol and limonene. They block proteins that stimulate cell growth and reproduction and are being tested for actions against cancer. Limonene is found in the peels of citrus fruits.

Organosulfurs are part of the allium family of phytochemicals. Compounds, such as allicin, may have benefits on the immune system, assist the liver in rendering carcinogens harmless, and reduce production of cholesterol in the liver. These compounds are found in garlic, leeks, onions, chives, scallions, and shallots.

Capsaicin seems to reduce levels of substance P, a compound that contributes to inflammation and the delivery of pain impulses from the central nervous system. Research suggests that it may inhibit cancer-generating substances. It is found in hot red peppers.

Sterols, which include sitosterol, stigmasterol, campesterol, and squalene, are found in vegetable oils. Sitosterol is the most studied and appears to have cholesterol-lowering effects.

Beta-sitosterols may help improve urine flow and urinary symptoms in men with enlarged prostate glands (benign prostatic hyperplasia, or BPH). A recent review study of five randomized trials (519 men) found that urinary flow and other urinary symptoms improved in men who took the herbal remedy from 4 - 26 weeks. The study’s authors cautioned that while beta-sitosterols show effectiveness in the short term, their long-term effectiveness, ability to prevent complications from BPH, and safety are not known. More research is necessary. Beta-sitosterols come from South African star grass, Hypoxis rooperi, or species of Pinus and Picea.

Healthy Foods

Evidence increasingly suggests that a varied diet, not individual food chemicals, is essential for basic health and a longer life. Such diets are rich in fresh fruits and vegetables and whole grains, and low in saturated fats.


Foods	Phytochemicals and Carotenoids	Vitamins and other valuable food components	Benefits
Apples	Flavonoids		May have activity against certain cancers (lung). Also may help maintain healthy cholesterol. May protect against asthma.
Beans	Flavonoids	Folate, iron, potassium, and zinc	Some experts believe beans are the perfect food.
Berries, all kinds of dark colored	Ellegic Acid	Vitamin C, minerals	The anthocyanins in berries such as bilberries, blueberries, cranberries, elderberries, and others, have numerous healthful properties including anti-cancer and antioxidant effects. Bilberry (Vaccinium myrtillis) is widely used to prevent macular degeneration. Blueberries may protect the aging brain. (In one study blueberries were most effective.)
Broccoli (also kale, Brussels sprouts, cauliflower)	Flavonoids, isothiocyanates, lutein, beta and alpha carotene. Note: Young sprouts of broccoli and cauliflower contain much higher levels of isothiocyanates than their mature forms.	Vitamin C, folate, fiber, and selenium	Anticancer properties. Protective against heart disease and stroke.
Carrots and other bright yellow vegetables	Lutein, beta carotene and other provitamin A carotenoids	Vitamin A (converted from carotenoids), vitamin C	Protects eyes, lungs. (Cooking carrots may increase the potency of food nutrients.)
Chocolate, dark. Note: Milk chocolate does not have benefits.	Flavonoids		Heart protective (may improve lipids and help prevent blood clotting. May have protective properties against lung cancer (not other cancers).
Eggs	Lutein	Many B vitamins, vitamin A, vitamin D	Although egg yolks are high in cholesterol, very little of it has a negative effect on people with normal levels. And the health benefits of eggs are now known to be very high. (People with diabetes or those with high cholesterol should restrict eggs, however.)
Fish, oily (mackerel, salmon, sardines)		Vitamin B3, B12. Essential fatty acids, selenium	Heart and brain protective.
Garlic	Allium (organosulfurs)		Possibly protective against certain cancers, heart diseases, and infection. Heating garlic can reduce benefits. Allowing crushed fresh garlic to stand 10 minutes before heating, however, may preserve beneficial chemicals while cooking.
Ginger	Zingiberaceae		Cancer fighting properties.
Grains (whole)	Lignans (phytoestrogens)	Vitamin B, Selenium (important antioxidant mineral), fiber, folate	May help reduce the ability of cancer cells to invade health tissue.
Grapes, including purple grape juice, and red wine	Flavonoids, (resveratrol, quercetin and catechin)		Fight heart disease and cancer. May help lower the risk for asthma.
Nuts		Vitamin E, vitamin B1, essential fatty acids, folate	Protects the heart and may help prevent stroke.
Onions	Flavonoids, allium (organosulfurs)		May have activity against certain cancers (lung).
Oranges	Monoterpenes	Vitamin C, folate, potassium.	Many health benefits. Increases HDL levels.
Potatoes (Sweet)		Vitamin C, vitamin E, vitamin A	Many health benefits.
Soy. The best products are tofu, soy milk, or whole soy protein.	Isoflavones (phytoestrogens), flavonoids, phytosterol, phytate, saponins.		May have effects similar to estrogen, including maintaining bone and benefiting the heart in women. May also be protective against prostate cancer and possibly other cancers. More studies are needed. Effects on breast cancer are uncertain. (Note: Soy may have different effects in men than in women. Of some concern is one study reporting more mental decline in men who consume greater amounts of tofu.)
Spinach and other dark green leafy vegetables	Zeaxanthin, Beta carotene	Vitamin C, folate, vitamin A (converted from carotenoids)	Protects lungs and brain.
Tea (Both black and green tea are beneficial. Best results associated with green tea.)	Flavonoids (primarily catechins)		Cancer fighting properties, particularly in green tea, which may be especially beneficial for smokers. Both black and green tea may protect against heart disease and stroke, although studies are mixed. Tea drinking also may help with weight control and help prevent osteoporosis.
Tomatoes	Lycopene, Flavonoids	Vitamin C, biotin, minerals	Studies link to reductions in prostate and other cancers. Infection fighters.
Note on Organic versus Inorganic Products. There is some evidence that organic produce has higher levels of antioxidants and that some agricultural chemicals may destroy flavonoids. Nevertheless, organic produce is expensive, and fruits and vegetables, no matter how they are grown, are still filled with healthful nutrients.

Dietary Health Benefits

The benefits of any dietary factors are very difficult to prove, and, to date, there is little evidence that most dietary supplements protect against major diseases in otherwise healthy people with normal eating habits. An exception is lutein, which is known to reduce the risk of macular degeneration. However, a diet naturally high in vitamins and minerals can be the best defense against many diseases. Fresh fruits and vegetables and whole grains are the primary sources of vitamins, carotenoids, and vitamins, as well as of fiber and important minerals.

Description of Oxygen-Free Radicals (Oxidants). Currently, the most important benefit claimed for vitamins A, C, E, and many of the carotenoids and phytochemicals is their role as antioxidants, which are scavengers of particles known as oxygen-free radicals (also sometimes called oxidants). These chemically active particles are by-products of many of the body's normal chemical processes. Their numbers are increased by environmental assaults, such as smoking, chemicals, toxins, and stress. In higher levels, oxidants can be very harmful in the following way:

They can damage cell membranes and interact with genetic material, possibly contributing to the development of a number of disorders including cancer, heart disease, cataracts, and even the aging process itself.
Oxygen-free radicals can also enhance the dangerous properties of low-density lipoprotein (LDL) cholesterol, a major player in the development of atherosclerosis.

Description of Antioxidants and Warnings on High-Dose Supplements. Antioxidant vitamins (A, C, and E), carotenoids, and many phytochemicals can neutralize free radicals. Unfortunately, although it is clear that vitamins are required to prevent deficiency diseases, high doses of vitamin C, vitamin E, and beta carotene supplements may also have pro-oxidant effects, which can be harmful in patients with cancer. In these people, high doses of antioxidant vitamins may actually protect cancer cells just as they do healthy cells.

The strongest evidence on negative effects to date comes from studies reporting an increase in lung cancer and overall mortality rates among smokers who took beta carotene supplements. In determining reasons for this disturbing effect, one animal study suggested that beta carotene increased enzymes in the lungs that actually promote cancerous changes. One study also reported a higher risk for cancer in male smokers who took multivitamins plus A, C, or E.

Some evidence also indicates that high doses of vitamin C may speed up atherosclerosis, or hardening of the arteries. In one study, women with heart disease who took antioxidant vitamins had a higher risk for heart attack or death than those who didn't take one.

Another study also reported a higher incidence and greater severity of respiratory infections in older adults who took 200 mg of vitamin E daily. Some researchers speculate that certain immune factors generate oxidants to fight bacteria. This antioxidant vitamin, then, may block that action. Research published in 2005 suggests that those who take large amounts of vitamin E (1,500 IU/day) may slightly increase their risk for heart failure and death, but this evidence is not considered conclusive. Further study is necessary.

Vitamins and Heart Protection.

Antioxidant Vitamins A, C, and E. Deficiencies in vitamins A, C, E, and beta carotene have been linked to heart disease. All of these nutrients have antioxidant effects and other properties that should benefit the heart. A study in patients with heart failure has shown that vitamin C can work with dobutamine, a powerful intravenous medication, to strengthen the heart’s ability to contract following a heart attack. In fact, a 2005 study has found that taking high doses of vitamin E is associated with an increased risk of heart failure. In 2007, the Women’s Antioxidant Cardiovascular Study failed to find that vitamins C, E, and beta carotene could reduce the risk of heart attack, stroke, need for revascularization, or cardiovascular death in women. According to the U.S. Preventive Service Task Force, evidence is insufficient to confirm or refute the benefits of supplements of any of these vitamins in protecting against heart disease.
Folate and B12 Vitamins. Deficiencies in the B vitamins folate (known also as folic acid) and B12 have been associated with elevated blood levels of homocysteine, an amino acid that has been associated with a higher risk for heart disease, stroke, and heart failure. One study, reported lower failure rates after heart surgery in patients who took folic acid and vitamins B12 and B6. And a major 2002 study suggested that lowering homocysteine levels with folic acid would reduce the risk for heart disease by 16% and stroke by 24%. However, a 2007 trial in adults with stable coronary artery disease found that lowering homocysteine levels 33% with B vitamins and folic acid had no effect on arterial inflammation, meaning that lower levels were unlikely to offer protection against heart attack or stroke. More evidence is needed to determine whether homocysteine plays a causal role in cardiovascular disease and whether the B vitamins are protective. Folate improves blood flow through the arteries, which may be important for the heart, regardless of its effect on homocysteine. Although people with high levels of homocysteine are prone to damaging blood clots in their arteries and veins, a 2007 study found that lowering homocysteine with folic acid and other B vitamins does not reduce the incidence of blood clots in the peripheral veins (deep venous thrombosis).
Niacin. Niacin (vitamin B3) is used for lowering unhealthy cholesterol levels. Although vitamin B3 is available over the counter, it can have significant side effects. A physician should prescribe niacin in order to ensure its safety and effectiveness. [See In-Depth Report #23, Cholesterol.]

Carotenoids and Heart Protection. Studies have reported that a diet high in fruits and vegetables containing beta carotene, lycopene, and other carotenoids may reduce the risk of heart attack. A small Finish study found that a diet high in tomatoes reduced total cholesterol and LDL ("bad") cholesterol. Diets low in lycopene (particularly from tomatoes) were associated with a significantly higher risk of heart disease and stroke.

Atherosclerosis is a disease of the arteries in which fatty material is deposited in the vessel wall, resulting in narrowing and eventual impairment of blood flow. Severely restricted blood flow in the arteries to the heart muscle leads to symptoms such as chest pain. Atherosclerosis shows no symptoms until a complication occurs.

Phytochemicals and Heart Protection. Several phytochemicals are associated with heart protection.

Flavonoids. Certain flavonoids, found in both black and green tea, dark chocolate, onions, red wine or red grape juice, and apples, appear to be strongly heart protective. In one study, people who consumed the most flavonoids in foods had a 20% lower risk for heart disease than those with low consumption. Flavonoids may protect against damage done by cholesterol and help prevent blood clots. A number of studies have now reported heart protection from the flavonoid catechin, which is found in both black and green tea. The flavonoid resveratrol, which is found in grape skin, appears to be responsible for the well-known heart protective effects in red wine and purple grape juice.
Organosulfurs. Organosulfurs found in onions and garlic have been under investigation for possible beneficial effects on cholesterol levels. One study reported an association between taking garlic capsules and significantly lower cholesterol-build up in the arteries of older women but not in older men. In the study, daily garlic supplements dramatically reduced the build-up of newly formed plaque in the arteries, while having much less effect on older, harder plaque deposits. Garlic supplements for cardiovascular disease may be most beneficial when used during earlier years among men and later years among women.
Isoflavones. Soy protein is the most studied source of isoflavones (known as phytoestrogens, or plant estrogens). Not all studies are consistent, but the majority has shown an improvement in at least one of the cholesterol components in people who consumed at least 25 grams of soy protein. A 2007 meta-analysis of all soy protein studies performed from 1990 - 2006 found that soy protein significantly decreased total cholesterol and LDL cholesterol, but had no effect on HDL or triglycerides. The effect was particularly evident in people with hypercholesterolemia. A 2007 study found that 12 weeks of soy supplement lowered total cholesterol and LDL levels in both Caucasian and African-American postmenopausal women. Soy may also reduce other heart risk factors, at least in certain populations. For example, in one 2002 study, soy was beneficial for controlling blood sugar and lowering LDL in postmenopausal women with type 2 diabetes. In a 2007 study of overweight men and postmenopausal women, soy protein reduced blood pressure and arterial stiffness. In another study, soy protein was associated with lower systolic blood pressure in men. The best sources are soy products (tofu, soy milk) or whole soy protein. Powdered soy protein that contains at least 60 mg of isoflavones may provide similar benefits.
Sterols. The plant sterols, including sitosterol, are also proving to be potent cholesterol fighters by blocking the absorption of cholesterol in the intestine. Sitostanol, a derivative of sitosterol, is being used in new margarine products to lower cholesterol levels. Sterols and stanols are now found in breads, cereals, yogurt, and fruit juices.

A healthy diet rich in fruits and vegetables and low in salt and saturated fats may significantly lower the risk for a first stroke, perhaps by helping to protect against high blood pressure -- a major risk factor for stroke.

Vitamins and Stroke Protection. The effects of antioxidant vitamins and carotenoids on stroke, dementia, or both are being studied. Studies are conflicting, however. A 2007 study of 8,171 women with cardiovascular disease reported that vitamins C, E, and beta carotene offered no protection against heart attack and stroke.

The B vitamin folate (usually in the form of folic acid) may protect against stroke. However, exactly which people benefit from this therapy has yet to be determined. Studies have suggested that people who have higher blood levels of folate have a lower than average risk for stroke. Its primary benefit in this case appears to be to reduce levels of homocysteine, an amino acid that has been strongly linked to an increased risk of coronary artery disease, stroke, and Alzheimer's disease. A 2007 meta-analysis of 8 trials found that folate supplements decreased homocysteine 20% and lowered stroke risk 18%. Interestingly, lowering homocysteine with folic acid and B vitamins had no effect on heart attack, strokes, amputations, need for dialysis, or death in patients with chronic or end-stage kidney disease.

Carotenoids and Stroke Protection. Some, but not all, studies have reported a lower risk of stroke from carotenoids, including beta carotene and lycopene.

Many fresh fruits and vegetables contain chemicals that may fight many cancers, including lung, breast, colon, and prostate cancers. Examples of important cancer fighting foods include the following:

Cruciferous vegetables (such as cabbage, Brussels sprouts, and broccoli)
Tomatoes (which contain lycopene)
Carrots (which contain alpha carotene)

Some evidence suggests that antioxidants may enhance the anticancer effects of chemotherapy. In multiple studies, patients who maintained their antioxidant levels were better able to withstand the high stress caused by chemotherapy or radiation therapy compared to those with low antioxidant levels. Antioxidant nutrients that may help reduce the side effects of chemotherapy include vitamins E and C, beta carotene, genistein and daidzein (isoflavones found in soy), and quercetin (found in red wine an purple grape juice).

Any protective effects of vitamins or specific phytochemical against cancer, however, appear to depend on the cooperative effort among them. Individual supplements of any vitamin or food chemical have not as yet shown any benefits.

Additionally, certain supplements may actually encourage tumor growth, particularly when taken in large amounts. Two 2007 studies found a connection between folate supplements and colorectal cancer. In one study, which was designed to evaluate the benefits of folic acid in patients who had previous colorectal adenomas (precancerous polyps), the researchers instead found that folic acid was associated with a higher risk of having 3 or more adenomas and noncolorectal cancers. In another study, it was noted that the downward trend in colorectal cancer diagnoses abruptly started to rise in 1996 when mandatory folate enrichment of grains within the U.S. and Canada began. Rates continue to exceed pre-1996 levels. Additionally, a large 2007 National Cancer Institute/AARP study found an increased risk of advanced and fatal prostate cancer in men who took more than 7 multivitamins a week, but no association between multivitamin use and localized prostate cancer.

High consumption of cruciferous vegetables (at least once per week) was associated with lower risk of kidney cancer, and low consumption (less than once per month) of cruciferous vegetables was associated with higher risk of kidney cancer in a multinational 2007 European study. Cruciferous vegetables also appear to offer protection against head and neck cancer resulting from chemical toxins found in cigarettes and alcohol, for example.

Vitamins and Cancer Protection. Because many cancers are thought to be initiated by the effects of oxygen-free radicals on DNA, the antioxidants A, C, and E and beta carotene have been intensively studied. A major study found that men who took selenium for 6 or 7 years reduced their risk of prostate cancer by 52%. Nevertheless, most individual supplements have not been proven to protect against cancer, and high doses may be dangerous.

A 2007 review of the diets of men exposed to asbestos found a decreased risk of prostate cancer associated with increasing intakes of vitamin C-rich vegetables, but not fruits and vegetables high in vitamin A. The chemopreventive role of silymarin (Silybum marianum), found in milk thistle extract, has been extensively studied and has shown anticancer efficacy against various cancers, especially prostate and skin, by inhibiting UVB radiation.

A review of 13 cancer registries found 416,134 cases of skin cancer and 3,776,501 cases of non-skin cancer as a first cancer. Rates from cancer registries in sunny countries (such as Australia and Spain) and less sunny countries (such as Canada and Iceland) were compared. The researchers concluded that vitamin D production in the skin decreases the risk of several solid cancers, especially stomach, colorectal, liver and gallbladder, pancreas, lung, female breast, prostate, bladder, and kidney cancers. The apparently protective effect of sun exposure against second primary cancer is more pronounced after non-melanoma skin cancers than melanoma.

Consumption of aflatoxins, a common fungus-related toxin infecting cereal grains, oil seeds, spices, tree nuts, and the milk of animals fed contaminated feed, is known to cause hepatocellular carcinoma, a deadly form of liver cancer. Rodent studies have shown that phenolic antioxidants, dithiolethiones, isothiocyanates, and triterpenoids may act as chemopreventive agents, dispersing aflatoxins and protecting against hepatocellular carcinoma. Human trials are planned. A similar study found that several isothiocyanates, diallyl sulfide, and polyphenolic compounds can prevent esophageal dysplasia from progressing to squamous cell carcinoma.

A review of all articles on vitamins and cancer published through February 2007 found that multivitamin/mineral supplement use may prevent cancer in individuals with poor or suboptimal nutritional status. One trial on poorly nourished Chinese showed supplementation with combined Beta-carotene, vitamin E and selenium reduced gastric cancer incidence and mortality, and overall cancer mortality. In a French trial, combined vitamin C, vitamin E, beta-carotene, selenium, and zinc reduced cancer risk in men but not in women. With few exceptions, neither beta-carotene nor vitamin E had benefits for preventing cancer. Beta-carotene supplementation increased lung cancer risk in smokers and persons exposed to asbestos.

A 2007 study of nearly 82,000 men and women in Sweden found that high intake of methionine was associated with reduced risk of pancreatic cancer. The same relationship was not seen with vitamin B6 or folate.

Vitamin A, C, and E. Although some studies have reported an association between low blood levels of these antioxidant vitamins and a higher risk for cancer, supplements of vitamins A, C, and E appear to have few advantages in most cases. And there are some studies finding higher cancer risks with high intakes of antioxidants. For example, a 2003 study reported a higher risk in melanoma in people with vitamin-C rich diets. Another study also reported a higher risk for cancer in male smokers who took multivitamins plus A, C, or E. (Vitamin E may be protective against bladder cancer and ovarian cancer.)
Vitamin D. Some studies have suggested that certain vitamin D compounds may inhibit certain cancer cells, specifically prostate cancer, from proliferating. More research is needed. In 2007, the National Cancer Institute confirmed that ultraviolet (UV) radiation exposure may reduce the risk of developing non-Hodgkin lymphoma (NHL), but only in patients with certain variations in the D vitamin receptor gene. A second 2007 study found that variations in this gene increase the risk of diffuse large B-cell lymphoma. A 2007 prospective analysis of 31,500 women in the Women’s Health Study evaluated calcium and vitamin D intake. The researchers found a moderately lower risk of premenopausal, but not postmenopausal, breast cancer with higher intakes of total calcium and vitamin D. A 2007 review of breast cancer cases reported in Ontario, Canada, found reduced breast cancer risks were associated with increasing sun exposure in women ages 10 - 19, less evidence for associations in women ages 20 - 29, and no evidence for ages 45 - 54. Researchers concluded that sun exposure earlier in life, particularly during breast development, may be key in the connection between vitamin D exposure and breast cancer risk.
Folic acid and B12. These B vitamins convert the amino acid homocysteine to methionine, a substance that helps prevent cells from becoming malignant. Folic acid may provide some protection against cervical and colon cancer. One small study showed a reduction of lung cancer cells in smokers taking folic acid and vitamin B12, but the study was very small, of short duration, and other factors might have biased the results. Still another study reported that folic acid may reduce the risk for breast cancer among women who regularly drink alcohol. (In the study, folic acid had no other effect on breast cancer.)

In 2006, a study for the National Institutes of Health reviewed randomized trials evaluating the effectiveness and safety of multivitamin and mineral supplements in preventing cancer and chronic disease. The studies had mixed results, and some supplements reduced cancer rates in certain populations. However, the reviewers concluded that current evidence is not sufficient to determine whether multivitamin and mineral supplements may prevent cancer and chronic disease.

Carotenoids and Cancer Protection. A number of studies have reported that fruits and vegetables rich in carotenoids are associated with protection against many cancers. Lycopene, found in tomatoes, may have particular value in protection against prostate, colon, lung, and bladder cancer. A 2005 study found that in one out of four men with genetic variations that cause them to be more sensitive to oxidative stress, supplementation with selenium, vitamin E, and lycopene significantly reduces the risk of prostate cancer. Individual supplements, however, do not offer any advantage. In fact, evidence now strongly suggests that beta carotene supplements increase the risk for lung cancer in smokers and people exposed to asbestos

Phytochemicals and Cancer Protection. The following phytochemicals appear to have cancer-protecting properties.

Isothiocyanates. Isothiocyanates and sulforaphane, found in cruciferous vegetables, may block the effects of carcinogens and suppress tumor growth. In one study, for example, women with the highest consumption of cruciferous vegetables had a 24% lower risk of breast cancer than women with the lowest consumption.
Isoflavones. Isoflavones, found in soy beans and flax seed, behave like estrogen in some ways and not in others. Researchers are very interested, then, in their effects on hormone-related cancers, including breast and prostate cancers. Much research has focused on soy. In general, a number of Asian studies have reported an association between a higher intake of soy and a lower incidence of reproductive and breast cancers. The effects of phytoestrogens, however, in all women are far from settled. Some evidence suggests the genistein in soy may have properties that are protective against lung cancer. Nonfermented soy products (tofu, soy milk) also may protect against stomach cancer, while fermented soy products (miso, soy paste) appears to increase the risk.
Organosulfurs. The organosulfur compounds found in the onion and garlic family may have very potent properties in suppressing or blocking carcinogenic substances. A 2007 study found that synthetic organosulfur compounds act as selective inhibitors of growth in breast cancer cells. Studies indicate that people who regularly consume fresh or cooked garlic have about half the risk of developing stomach cancer and two thirds the risk of colorectal cancer as people who eat little or no garlic. One possible explanation for garlic's anti-cancer effect in the stomach is its antibacterial action against H. pylori, which can promote stomach cancer. Taking garlic supplements, however, did not offer these benefits.

It should be noted that studies on the health benefits of vitamins and minerals have some important limitations. Some are held to rigorous standards, while others are not. In most cases, the results of existing research are complex, as they can easily be complicated by factors such as diet, exercise, the presence of healthy or unhealthy lifestyle behaviors, environmental factors, and more.


Disease or Condition	Vitamins	Carotenoids, Phytochemicals, and Healthy Foods
Alzheimer's Disease	Vitamin E. Some reports, including a large 2002 population study, have suggested that vitamin E intake, from food or supplements, may protect against mental decline. (One study suggested that the vitamin protected only those who carried the apoE4 gene. No strong evidence to date has found any protection from antioxidant supplements.) Some studies performed since 2002 challenge this finding, while others agree with it. B Vitamins. Some studies suggest that deficiencies of the B vitamins B6, B12, and folate may be a risk factor for Alzheimer' diseases, possibly because deficiencies elevate homocysteine levels, which some research now associated with a higher risk for Alzheimer's disease. Of these, folates may offer the best protection. In 2007, researchers at Tufts-New England Medical Center reviewed all human studies on folate, vitamin B-6, vitamin B-12, and cognitive function in the elderly conducted between 1966 and November 2006. Six of 10 folate studies reported a significant association between low baseline blood folate concentrations and poor cognitive test performance; 4 of 9 folate studies found associations between low blood folate concentrations and increased prevalence of Alzheimer's disease. No association between vitamin B-6 and vitamin B-12 blood concentrations and cognitive-test performance or Alzheimer's disease was seen, and B-vitamin dietary intake was not associated with cognitive function. Although the majority of studies indicated that low blood folate concentrations predicted poorer cognitive function, data are not solid, due to variations in the way the studies were conducted and lack of agreement on what constitutes a low B-vitamin status.	According to several studies, eating plenty of darkly colored fruits and vegetables may slow brain aging. The estrogen-like properties in isoflavones are of interest in the study of Alzheimer's disease. Animal studies suggest that soy might be protective against AD, particularly in postmenopausal women. Of some concern, however, were one population and a few animal studies suggesting that soy intake may pose a risk for greater mental decline among older men. More research is needed to confirm the effects of soy on the aging brain and to determine if there are gender differences.
Infectious Disease	Studies are mixed whether vitamin supplements protect against upper respiratory infections. Large doses of vitamin C, for example, may help reduce the duration of a cold, but they do not appear to protect against one in the first place, even after exposure to a cold virus. Two studies in 2002 on multivitamins reported opposite results, with one finding fewer infections and one finding no difference. It is possible that vitamin C or multivitamin supplements may be helpful in specific people, such those who are vitamin deficient or have medical problems that impair their immune systems. A review of all studies on vitamin C and pneumonia prevention found only 1 placebo-controlled, randomized trial conducted in an English boarding school during World War II. The trial found a statistically significant (80% or greater) reduction in pneumonia incidence among boys consuming vitamin C. Two less-well-constructed trials arrived at the same conclusion. Therapeutic trials were even scarcer. Only one randomized, double-blind, placebo-controlled study of vitamin C for treatment of pneumonia was found. In this trial, elderly patients given vitamin C had lower mortality and respiratory symptom scores. However, the benefits were restricted to the sickest patients. One other trial of adults in the former Soviet Union found a dose-dependent reduction in the time to recover with two vitamin C doses. One 2007 study on vitamin D found that a single dose by mouth of this vitamin might prevent healthy individuals from activating the bacterium that causes tuberculosis in patients who harbor the infection. Studies on vitamin E specifically have been mixed. A 2002 study, in fact, reported a higher incidence and greater severity of respiratory infections in older adults who took 200 mg of vitamin E daily. However, a 2004 clinical trial conducted among elderly nursing home residents found that daily supplementation with 200 IU of vitamin E did provide protection from upper respiratory infections, especially the common cold. At present, there is not enough evidence to recommend vitamin E for infection prevention. Diarrhea is a worldwide problem, particularly in developing countries and those with poor sanitation. Taking supplements with B-complex vitamins, vitamin C, vitamin E, and selenium may reduce the risk of diarrhea, depending upon the organism that causes the disease. Meanwhile, iron supplements appear to increase the risk of infection from organisms that cause diarrhea. Vitamin A has not been shown to prevent diarrhea. Urinary tract infections (UTIs) may affect as many as 25% of pregnant women. A 2007 study found that women who took vitamin C (100 mg) for 3 months had significantly fewer UTIs than women who did not take vitamin C supplements. Rotavirus is a common cause of acute gastric pain in children under age 5. A 2007 study showed that the high amount of isoflavones found in soy-based infant formula can help prevent rotavirus infection.	Lycopene, found in tomatoes, appears to have properties that protect infection-fighting white blood cells. Saponins extracted from ginseng and allicin (found in garlic) have properties that boost the immune system. Both ginseng and garlic have long been traditionally used for their health benefits.
Asthma	Vitamin C from diet has been associated with lower risk for asthma. In one study, some people with exercise-induced asthma benefited from taking vitamin C one hour before strenuous physical activity. In a 2007 study, taking 1,500 mg supplements of vitamin C for 2 weeks helped prevent exercise-induced airway narrowing in patients with asthma.	Flavonoids found in apples and red wine may help lower the risk for asthma. Some evidence indicates that a low dietary intake of antioxidant nutrients could increase the risk for lung damage. Such nutrients should be obtained from fresh, deep green and yellow-orange fruits and vegetables. A 2007 study found low blood lycopene levels in people with asthma. Increasing lycopene- and vitamin A-rich foods may help raise lycopene levels.
Eye Disorder	Cataracts and Macular Degeneration. Oxygen-free radicals play a role in cataract formation and age related macular degeneration, the most common cause of irreversible blindness in the elderly. Bilberry (Vaccinium myrtillis), which contains powerful anthocyanins, is widely used to prevent macular degeneration. Low levels of vitamin C in the lens of the eye have been particularly strong predictors of cataracts. People with cataracts are frequently deficient in vitamin A, the carotenes, lutein, and zeaxanthin. Studies on protection against cataracts using antioxidant supplements have been mixed, including two identically conducted studies that reported opposite results. Vitamin C currently has the strongest evidence for protection, but even with this antioxidant studies are not consistent. A combination of zinc and antioxidants, including vitamin C and E, may slow the progression of macular degeneration. (Vitamin E alone does not appear to be protective.) Glaucoma. Although no evidence exists that antioxidants will prevent glaucoma, some studies reported an association between vitamin E and improved visual fields in patients with glaucoma.	Several studies report that the consumption of antioxidant-rich foods is associated with a decreased risk for cataracts. Carotenoids, especially lutein, lycopene, and zeaxanthin, are especially eye-protective and may help prevent cataracts and macular degeneration. The National Eye Institute in 2007 suggested that people with intermediate- or advanced macular degeneration in one eye may want to take a vitamin formula shown to reduce the risk of macular degeneration in the other eye by 25%. The formula contains vitamin C, vitamin E, beta-carotene, and zinc. They also suggest that a diet high in lutein and zeaxanthin may help reduce the risk of advanced age-related macular degeneration. Several studies report that the consumption of antioxidant-rich foods is associated with a decreased risk for cataracts. Carotenoids, especially lutein lycopene, and zeaxanthin are especially eye-protective and may help prevent cataracts and macular degeneration.
Skin Disorders and Wrinkles	Topical vitamin A (retinol) has been shown to improve fine wrinkles due to aging, by increasing glycosaminoglycan, which retains water, and increasing collagen production. One small study found that taking a combination of vitamins oral C and E supplements may help reduce sunburn reactions, although the protection is much less than from sunscreens. Taking the vitamins singly did not have any effect. In fact, a 2002 study reported that oral vitamin C had no effect on sunburn reaction. Of concern, in the same study some natural antioxidants in the body were reduced in people who took the vitamin. Also of concern are studies reporting no benefits and possibly harm from topical vitamin C in the form of ascorbyl palmitate, which is soluble in fat. One study reported that older adults had fewer wrinkles if they ate whole grains, fresh fruits and vegetables, and the use of healthy oils (such as olive oil). Diet played a role in improving skin regardless of whether the people in the study smoked or lived in sunny countries.	The following foods and phytochemicals may be especially skin protective: Both green tea and ginger appear to have properties that may provide some protection against skin cancer. Green tea skin care products are now available. The substance silymarin, found in the milk thistle family (which includes artichokes), may inhibit UVB-promoted cancers in animals. In one interesting study, eating garlic protected animals very effectively against UVB damage by interfering with urocanic acid in the skin. Whether these results may apply to humans (and what quantities of garlic might be beneficial) is still unknown.
Osteoporosis	Vitamin D. Vitamin D is the essential companion to calcium in maintaining strong bones. Supplements may be needed for people who have poor exposure to sunlight. It should be noted that diet supplies most people's need and high amounts of vitamin D can be toxic. Of interest: Taking vitamin D supplements does not prevent bone loss in post-menopausal African American women, according to research published in 2005. Further study will be needed to determine whether vitamin D prevents bone loss in women from other ethnic groups. Vitamin K. Studies suggest that vitamin K has properties that protect bone and prevent fracture. Vitamin K2 (menatetrenone), a form of vitamin K, is proving to prevent fractures in people with osteoporosis. Vitamin K affects blood clotting, and supplements are not recommended without specific physician instruction. Vitamin B12. One study reported that in people with osteoporosis and pernicious anemia, taking vitamin B12 (which is used to treat the anemia) also increased bone density. Vitamin C and E. There has been some indication of a positive association between vitamin C and E intake and bone density, although evidence proving actual benefits is weak. Note on Vitamin A. High amounts of dietary vitamin A reduces bone density and may even increase the risk for fracture in both postmenopausal women and men. (A form of vitamin A, retinoic acid, has been found to stimulate bone break down.) Beta carotene does not appear to increase risk. Studies suggest that diets rich in fresh fruits and vegetables (which include those high in potassium and magnesium) reduce elimination of calcium from the body and help preserve bones.	Studies suggest that diets rich in fresh fruits and vegetables (which include those high in potassium and magnesium) reduce elimination of calcium from the body and help preserve bones. Studies are suggesting that isoflavones-rich soy products may actually improve bone density in postmenopausal women. A 2007 study of postmenopausal women in Italy found that 24 months of treatment with genistein plus calcium and vitamin D increased bone density, while women who took calcium and D alone lost bone density. Flavonoids and other compounds in tea may protect the bones.
Menstrual Disorders	Vitamin B6. Limited clinical evidence suggests that vitamin B6 may be beneficial in reducing premenstrual symptoms, including depression. Typically, women take 100 mg per day, although one study suggested that a lower dose (50 mg) may have the same effect. Other preliminary research indicates that women who receive the equivalent of 1,200 mg of calcium and 400 IU of vitamin D per day (through food or supplements) have a significantly lower incidence of premenstrual symptoms than women who did not. Vitamin B1. One study reported relief from menstrual pain using vitamin B1 (thiamin). Vitamin E. Several randomized controlled trials have shown that vitamin E significantly improves both physical and emotional premenstrual symptoms. One study reported that high doses of vitamin E helped reduce menstrual cramps. The doses were much higher than those recommended and could possibly increase the risk for bleeding. Although anecdotal evidence reports that vitamin E helps reduce the frequency of hot flashes for menopausal women, there is no clinical evidence to support this claim.

Resources

http://fnic.nal.usda.gov -- The Food and Nutrition Information Center
http://dietary-supplements.info.nih.gov -- Office of Dietary Supplements, National Institutes of Health
www.ars.usda.gov/ba/bhnrc/ndl -- Nutrient Data Laboratory
www.fda.gov -- Food and Drug Administration
www.eatright.org -- The American Dietetic Association
www.acsh.org -- American Council on Science and Health
www.aicr.org -- American Institute for Cancer Research
www.nutritiondata.com -- Information on vitamins and nutrients in foods
www.consumerlab.com -- Independent testing of nutritional supplements' contents and quality
www.usp.org -- US Pharmacopeia
www.herbs.org -- Herb Research Foundation

References

Age-Related Eye Disease Study Research Group, SanGiovanni JP, Chew EY, Clemons TE, Ferris FL 3rd, Gensler G, Lindblad AS, Milton RC, Seddon JM, Sperduto RD. The relationship of dietary carotenoid and vitamin A, E, and C intake with age-related macular degeneration in a case-control study: AREDS Report No. 22. Arch Ophthalmol. 2007;125(9):1225-1232.

Ambrosini GL, de Klerk NH, Fritschi L, Mackerras D, Musk B. Fruit, vegetable, vitamin A intakes, and prostate cancer risk. Prostate Cancer Prostatic Dis. 2007 May 22; [Epub ahead of print]

Aubertin-Leheudre M, Lord C, Khalil A, Dionne IJ. Six months of isoflavone supplement increases fat-free mass in obese-sarcopenic postmenopausal women: a randomized double-blind controlled trial. Eur J Clin Nutr. 2007 Feb 21; [Epub ahead of print]

Bermudez Y, Ahmadi S, Lowell NE, Kruk PA. Vitamin E suppresses telomerase activity in ovarian cancer cells. Cancer Detect Prev. 2007;31(2):119-28. Epub 2007 Feb 28.

Bodnar LM, Catov JM, Simhan HN, Holick MF, Powers RW, Roberts JM. Maternal vitamin d deficiency increases the risk of preeclampsia. J Clin Endocrinol Metab. 2007 ;92(9):3517-22. Epub 2007 May 29.

Clements RH, Katasani VG, Palepu R, Leeth RR, Leath TD, Roy BP, Vickers SM. Incidence of vitamin deficiency after laparoscopic Roux-en-Y gastric bypass in a university hospital setting. Am Surg. 2006;72(12):1196-202.

Coull DB, Tait RC, Anderson JH, McKee RF, Finlay IG. Vitamin B12 deficiency following restorative proctocolectomy. Colorectal Dis. 2007;9(6):562-566.

Dietary Guidelines for Americans 2005. Dept of Health and Human Services, US Dept of Agriculture. Accessed 10/3/2007.

Fischer Walker CL, Black RE. Micronutrients and diarrheal disease. Clin Infect Dis. 2007;45 Suppl 1:S73-S77.

Glynn RJ, Ridker PM, Goldhaber SZ, Zee RY, Buring JE. Effects of random allocation to vitamin E supplementation on the occurrence of venous thromboembolism: report from the Women's Health Study. Circulation. 2007;116(13):1497-503.

Headstrom PD, Rulyak SJ, Lee SD. Prevalence of and risk factors for vitamin B(12) deficiency in patients with Crohn's disease. Inflamm Bowel Dis. 2007 Sep 20; [Epub ahead of print]

Inderjeeth CA, Glennon D, Petta A, Soderstrom J, Boyatzis I, Tapper J.Vitamin D and muscle strength in patients with previous fractures. N Z Med J. 2007;120(1262):U2730.

Ishihara J, Otani T, Inoue M, Iwasaki M, Sasazuki S, Tsugane S; Japan Public Health Center-based Prospective Study Group. Low intake of vitamin B-6 is associated with increased risk of colorectal cancer in Japanese men. J Nutr. 2007;137(7):1808-1814.

J.G. Ray, C. Kearon, Q. Yi, P. Sheridan, and E. Lonn, for the Heart Outcomes Prevention Evaluation 2 (HOPE-2) Investigators. Randomized Trial of Homocysteine-Lowering Therapy and Risk for Venous Thromboembolism. Ann Intern Med. 2007;146(11):761-767.

Kitchin B, Morgan SL. Not just calcium and vitamin D: other nutritional considerations in osteoporosis. Curr Rheumatol Rep. 2007;9(1):85-92.

Kune G, Watson L. Colorectal cancer protective effects and the dietary micronutrients folate, methionine, vitamins B6, B12, C, E, selenium, and lycopene. Nutr Cancer. 2006;56(1):11-21.

Lim MR, Huang RC, Wu A, Girardi FP, Cammisa FP Jr. Evaluation of the elderly patient with an abnormal gait. J Am Acad Orthop Surg. 2007;15(2):107-117.

Martin H, Lindblad B, Norman M. Endothelial function in newborn infants is related to folate levels and birth weight. Pediatrics. 2007;119(6):1152-1158.

Mason JB, Dickstein A, Jacques PF, Haggarty P, Selhub J, Dallal G, Rosenberg IH. A temporal association between folic acid fortification and an increase in colorectal cancer rates may be illuminating important biological principles: a hypothesis. Cancer Epidemiol Biomarkers Prev. 2007;16(7):1325-1329.

Nardin RA, Amick AN, Raynor EM. Vitamin B(12) and methylmalonic acid levels in patients presenting with polyneuropathy. Muscle Nerve. 2007;36(4):532-535.

Ochoa-Brust GJ, Fernández AR, Villanueva-Ruiz GJ, Velasco R, Trujillo-Hernández B, Vásquez. Daily intake of 100 mg ascorbic acid as urinary tract infection prophylactic agent during pregnancy. Acta Obstet Gynecol Scand. 2007;86(7):783-787.

Parekh N, Chappell RJ, Millen AE, Albert DM, Mares JA. Association between vitamin D and age-related macular degeneration in the Third National Health and Nutrition Examination Survey, 1988 through 1994. Arch Ophthalmol. 2007;125(5):661-669.

Pham DQ, Plakogiannis R. Vitamin E supplementation in Alzheimer’s disease, Parkinson’s disease, tardive dyskinsia, and cataract: Part 2. Ann Pharmacother. 2005;39(12): 2065-2072.

Riccioni G, Bucciarelli T, Mancini B, Di Ilio C, Della Vecchia R, D'Orazio N. Plasma lycopene and antioxidant vitamins in asthma: the PLAVA study. J Asthma. 2007;44(6):429-432.

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Sahin M, Tutuncu NB, Ertugrul D, Tanaci N, Guvener ND. Effects of metformin or rosiglitazone on serum concentrations of homocysteine, folate, and vitamin B12 in patients with type 2 diabetes mellitus. J Diabetes Complications. 2007;21(2):118-123.

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Triantafyllou NI, Kararizou E, Angelopoulos E, Tsounis S, Boufidou F, Evangelopoulos ME, Nikolaou C, Vassilopoulos D. The influence of levodopa and the COMT inhibitor on serum vitamin B12 and folate levels in Parkinson's disease patients. Eur Neurol. 2007;58(2):96-99.

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Wierzbicki AS. Homocysteine and cardiovascular disease: a review of the evidence. Diab Vasc Dis Res. 2007;4(2):143-50.

Zeisel SH. The fetal origins of memory: the role of dietary choline in optimal brain development. J Pediatr. 2006;149(5 Suppl):S131-136.

Ziaei S, Kazemnejad A, Zareai M. The Effect of Vitamin E on Hot Flashes in Menopausal Women. Gynecol Obstet Invest. 2007;64(4):204-207 [Epub ahead of print]

Zollinger PE, Tuinebreijer WE, Breederveld RS, Kreis RW. Can vitamin C prevent complex regional pain syndrome in patients with wrist fractures? A randomized, controlled, multicenter dose-response study. J Bone Joint Surg Am. 2007;89(7):1424-1431.

Review Date:
10/29/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

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adam.com

Anemia

FitSugar — Wed, 08 Oct 2008 17:34:56 -0700

In This Report

Highlights
Introduction
Causes
Risk Factors
Complications
Symptoms
Diagnosis
Dietary Factors
Treatment
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

FDA Issues Labeling Changes for Drugs That Boost Red Blood Cells

In November 2007, the U.S. Food and Drug Administration (FDA) made several changes to the prescribing labels for erythropoiesis-stimulating drugs. These drugs -- epoietin alfa (Epogen, Procrit) and darbepoetin alfa (Aranesp) -- increase the production of red blood cells. They are used to treat anemia associated with chronic kidney failure, cancer chemotherapy, and antiretroviral HIV therapy.

The new labels have stronger warnings and updated dosing-related safety information. The FDA advises:

For cancer, erythropoiesis-stimulating drugs are used only to treat anemia associated with chemotherapy. Dosing should increase hemoglobin levels to no more than 12 g/dL. These drugs can shorten survival time and increase tumor growth when hemoglobin levels are raised beyond this point. Treatment should stop as soon as chemotherapy is completed. Erythropoiesis-stimulating drugs are not safe or appropriate for all patients undergoing chemotherapy. Patients should discuss the risks and benefits with their oncologists.
For chronic kidney failure, erythropoiesis-stimulating drugs should be used to maintain a hemoglobin level between 10 - 12 g/dL. Higher hemoglobin levels increase the risk for stroke, heart attack, heart failure, or death.
Erythropoiesis-stimulating drugs are used to increase red blood cell numbers and reduce the need for blood transfusions. They do not help improve anemia symptoms, fatigue, or quality of life for patients with cancer or HIV.
Patients who take these drugs should contact their doctors if they experience symptoms such as leg pain or swelling, increased shortness of breath, increased blood pressure, dizziness, or extreme fatigue.

Introduction

Anemia is an abnormal reduction in red blood cells.

This photmicrograph shows normal red blood cells (RBCs) as seen in the microscope after staining.

Anemia is a global problem, at its worst in developing countries. But it is by no means absent in industrialized nations. An estimated 3.4 million Americans suffer from anemia. Anemia is not a single disease but a condition, like fever, with many possible causes and many forms. Causes of anemia include nutritional deficiencies, inherited genetic defects, medication-related side effects, and chronic disease. It can also occur because of blood loss from injury or internal bleeding, the destruction of red blood cells, or insufficient red blood cell production. The condition may be temporary or long-term, and can manifest in mild or severe forms.

As it is impossible to discuss all types of anemia, this report focuses on three of the most common forms:

Iron deficiency anemia
Anemia of chronic disease (ACD)
Megaloblastic anemia (caused by deficiencies in the B vitamins folate, vitamin B12, or both)

Some less common causes and types of anemia are included in a table in this report.

Blood has two major components:

Plasma is a clear yellow liquid that contains proteins, nutrients, hormones, electrolytes, and other substances. It constitutes about 55% of blood.
White and red blood cells and platelets make up the balance of blood. The white cells are the infection fighters for the body, and platelets are necessary for blood clotting. The important factors in anemia, however, are red blood cells.

Red blood cells (RBCs), also known as erythrocytes, carry oxygen throughout the body to nourish tissues and sustain life. Red blood cells are the most abundant cells in our bodies. Men have about 5.2 million red blood cells per cubic millimeter of blood, and women have about 4.7 million per cubic millimeter of blood.

Hemoglobin and Iron

Each red blood cell contains 200 - 300 hemoglobin molecules. Hemoglobin is a complex molecule, and it is the most important component of red blood cells. It is composed of protein (globulin) and a molecule (heme), which binds to iron.

In the lungs, the heme component binds to oxygen in exchange for carbon dioxide. The oxygenated red blood cells are then transported to the body's tissues, where the hemoglobin releases the oxygen in exchange for carbon dioxide, and the cycle repeats. The oxygen is used in the mitochondria, the power source within all cells.

Red blood cells typically circulate for about 120 days before they are broken down in the spleen. Most of the iron used in hemoglobin can be recycled from there and reused.

Structure and Shape of Red Blood Cells

Red blood cells -- the erythrocytes -- are extremely small and look something like tiny, flexible inner tubes. This unique shape offers many advantages:

It provides a large surface area to absorb oxygen and carbon dioxide.
Its flexibility allows it to squeeze through capillaries, the tiny blood vessels that join the arteries and veins.

Abnormally shaped or sized erythrocytes are typically destroyed and eliminated.

Blood Cell Production (Erythropoiesis)

The actual process of making red blood cells is called erythropoiesis. (In Greek, erythro means "red," and poiesis means "the making of things.") The process of manufacturing, recycling, and regulating the number of red blood cells is complex and involves many parts of the body:

The body carefully regulates its production of red blood cells so that enough are manufactured to carry oxygen but not so many that the blood becomes thick or sticky (viscous).
Most of the work of erythropoiesis occurs in the bone marrow. In children younger than 5 years old, the marrow in all the bones of the body is enlisted for producing red blood cells. As a person ages, red blood cells are eventually produced only in the marrow of the spine, ribs, and pelvis.
If the body needs more oxygen (at high altitudes, for instance), the kidney triggers the release of the hormone erythropoietin (EPO), a hormone that acts in the bone marrow to increase the production of red blood cells.
The lifespan of a red blood cell is 90 - 120 days. The liver and the spleen remove old red blood cells are removed from the blood by the liver and spleen.
When old red blood cells are broken down for removal, iron is returned to the bone marrow to make new cells.

Click the icon to see an image of the formed elements of blood.

Click the icon to see an image of hemoglobin.

Causes

Iron deficiency anemia occurs when the body lacks mineral iron to produce the hemoglobin it needs to make red blood cells. In general, there are three stages leading from iron deficiency to anemia:

First, there is an insufficient supply of iron, which causes iron stores in the bone marrow to be depleted. This stage generally has no symptoms.
Second, iron deficiencies develop and begin to affect hemoglobin production. (Tests will show low hemoglobin and hematocrit levels.)
Hemoglobin production declines to the point where anemia develops.

Most of the iron used in the body can be recycled from blood and reused. Nevertheless, iron deficiency can occur from a number of conditions.

Inadequate Iron Intake. A healthy diet easily provides enough iron. In general, most people need just 1 mg, and menstruating women need 2 mg of extra iron each day. This means that lack of iron in the diet is not a common cause of iron deficiency anemia, except in infants. In fact, most American adults may be consuming too much iron in their diet. Most of the iron in red blood cells is recycled and reused. Iron-poor diets are a cause of anemia only in people with existing risks for iron deficiency. Children who have not yet eaten iron-fortified formulas or iron-enriched cereal may also become anemic.

Blood Loss. Iron deficiencies most commonly occur from internal blood loss due to other conditions that range in severity. These conditions include:

Peptic ulcers, which may be caused by H. pylori infections, or aspirin and drugs or nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen. About 70% of long-term users of these medications have some sign of gastrointestinal bleeding, although it is rarely significant enough to cause anemia.
Duodenal ulcers
Hemorrhoids
Colon polyps
Colon, stomach, and esophageal cancer
Very heavy periods (menorrhagia) are the most common causes of anemia in premenopausal women.
Bleeding from esophageal varices, often present in alcoholics

Impaired Absorption of Iron. Impaired absorption of iron is caused by:

Certain intestinal diseases (inflammatory bowel disease, celiac disease)
Surgical procedures, particularly those involving removal of parts of the stomach and small intestine, can impair the ability of the stomach or intestine to absorb iron. (Such conditions also often impair folic acid absorption as well.)
Pica, the craving for non-food substances such as ice, starch, or clay, is a possible cause of iron deficiency. To complicate matters, pica (particularly ice cravings) may also be a symptom, rather than a cause, of anemia.
Certain intestinal infections, such as hookworm and other parasites.

Click the icon to see an image of inflammatory bowel disease.

Genetic Causes. Some people are born with iron deficiency. Certain cases may be due to a mutation of the Nramp2 gene, which regulates a protein responsible for delivering iron to the cells.

Anemia of chronic disease (ACD), also called anemia of chronic inflammation (ACI), is a common condition associated with a wide variety of persistent inflammatory diseases. It can be very severe and require transfusions.

The Inflammatory Process and ACD. ACD is not completely understood. In ACD, iron is not efficiently recycled from blood cells, and red blood cell survival is reduced. In addition, there is impaired response to erythropoietin, the hormone that acts in the bone marrow to increase the production of red blood cells. (Abnormal function and low levels of erythropoietin, in fact, may be the most important factor in ACD, with iron insufficiencies being a consequence.)

The process leading to ACD may occur in the following way:

The immune system activates white blood cells and releases various compounds during times of infection that are intended to fight invaders and heal wounds. Such an event causes an inflammatory state in the areas of the attack.
White blood cells called macrophages release small but powerful proteins known as cytokines, which are critical in the development of ACD. Cytokines are indispensable for healing. However, cytokines are overproduced often in chronic and inflammatory diseases, causing serious tissue injury and, in some cases, even organ damage. In the case of ACD, they prevent production of erythropoietin, the hormone that acts in the bone marrow to increase the production of red blood cells. Specific cytokines implicated in anemia are interleukin 1 (IL-1), tumor necrosis factor (TNF), and interferons.
As part of this process, mechanisms prevent the release of recycled iron needed in the bone marrow for the manufacturing of red blood cells. Iron absorption in the intestines is also blocked. Theoretically, this is a protective measure, since iron may help infectious organisms proliferate. In such cases, iron stores are high, but the usable iron in circulation is low.
Researchers have identified a peptide called hepcidin, which prevents iron absorption in the intestine and blocks the release of iron by immune factors for red blood cell production. Some experts believe high levels of the peptide may play a central role in preventing the release of iron during infection and inflammatory states, and is critical in ACD.

Diseases Associated with ACD and Inflammation. The chronic diseases that are associated with this process include:

Certain cancers. Examples include lymphomas and Hodgkin's disease.
Autoimmune diseases. Examples include rheumatoid arthritis, systemic lupus erythematosus, inflammatory bowel disease, and polymyalgia rheumatica.
Long-term infections. Examples include chronic or recurrent urinary tract infections and osteomyelitis.
Hepatitis C. The liver cirrhosis associated with hepatitis C can reduce the production of red blood cells. Gastrointestinal bleeding may also contribute to blood loss.
Heart failure. Experts estimate that 25 - 60% of patients with heart failure also have anemia. However, it is unclear whether anemia actually causes or worsens heart failure. Recent research suggests it may actually be a sign (marker) of heart failure. Iron deficiency in heart failure can be due to a number of factors. It may be caused by a lack of nutrients in a person’s diet or by the body’s inability to absorb nutrients from food. Heart failure can also cause a back up of fluid (edema). This edema produces a higher volume of blood plasma (the liquid part of blood), which can dilute red blood cells and cause anemia.
Chronic kidney disease. The hormone erythropoietin (EPO) is produced in the kidneys and stimulates the bone marrow production of red blood cells. Diseased kidneys do not release sufficient amounts of EPO; anemia can result and is universal in end-stage renal disease. Chronic kidney disease is a common complication of diabetes.
HIV/AIDS. The inflammatory process associated with AIDS can adversely affect EPO levels and red blood cell production.
Anemia in critically ill patients. Evidence suggests similarities between ACD and severe anemia in patients who are in intensive care. Some experts believe that the cause of anemia in such critically ill patients may also be due to inflammatory responses that promote impaired responsiveness to erythropoietin.

Not all chronic diseases involve the inflammatory process and anemia. For example, high blood pressure is a chronic disease, but it does not affect red blood cells.

Treatment-Related Anemia. Anemia can also result from the therapies used to treat conditions. For example, anemia is a common side effect of cancer treatments. Chemotherapy and radiation can impair the bone marrow's production of red blood cells and contribute to the extreme fatigue that many patients experience during cancer therapy. Patients with hepatitis C frequently receive combination therapy of ribavirin and interferon; ribavirin can induce anemia. Hepatitis C also affects many patients with HIV or AIDS. In addition to ribavirin, patients with HIV or AIDS can develop anemia as a result of highly active anti-retroviral therapy (HAART) and, in particular, from the drug AZT.

Other medications that increase the risk for anemia are certain antibiotics, some antiseizure medications (phenytoin), immunosuppressive drugs (methotrexate, azathioprine), antiarrhythmic drugs (procainamide, quinidine), and anti-clotting drugs (aspirin, warfarin, heparin).

Megaloblastic anemia is the end-product of deficiencies in the B vitamins folate or vitamin B12 (also called cobalamin), or both. Such deficiencies produce abnormally large red blood cells (megaloblastic ) that have a shortened lifespan. Neurologic problems are also associated with these deficiencies. Several conditions can cause these deficiencies.

Click the icon to see an image of red blood cells seen in megaloblastic anemia.

Causes of Vitamin B12 Deficiency. Conditions that cause vitamin B12 deficiencies include:

Vitamin B12 deficiency from diet is very rare, since the liver stores over a 3-year supply. It usually does not occur even in alcoholism, vegetarianism, or in malnourished people with kidney failure or cancer. Since animal products are the chief source, however, true vegan vegetarians may need a supplement, fortified food, or appropriate food selection known to contain adequate amounts of this vitamin
Pernicious anemia. Pernicious anemia is an autoimmune disease in which antibodies are tricked into attacking stomach cells. This results in impaired production of intrinsic factor (IF), a compound that is critical for absorption of vitamin B12. Pernicious anemia is diagnosed in about 1% of people over age 60, with women having a higher risk than men.
Complications of gastrointestinal surgery. Surgeries such as stomach bypass or stapling, which remove part or all of the stomach, pose a 15 - 30% chance of causing vitamin B12 deficiencies.
Overgrowth of intestinal bacteria
Tropical sprue (an acquired malabsorption disease occurring in tropical climates)

Click the icon to see an image of the benefits of vitamin B12.

Causes of Folate Deficiency. The body stores only about 100 times its daily requirements for folate and can exhaust this supply within about 3 months if the diet is deficient in folate.

Poor diet coupled with alcoholism is the most common cause of folate deficiency. Alcohol abuse not only contributes to malnutrition but also causes chemical changes that can result in lower folate levels.
Any condition that disturbs the small intestine and impairs its absorption ability can cause a deficiency. Such disorders include inflammatory bowel disease or celiac sprue (a sensitivity reaction to gluten)

Click the icon to see an image of foods that contain gluten.

Parasitic diseases such as giardiasis
Short bowel syndrome
Deficiencies can also arise due to high demand for folic acid caused by conditions such as cancer, pregnancy, severe psoriasis, severe hyperthyroidism, and hemolytic anemia.
Some drugs, including phenytoin, methotrexate, trimethoprim, and triamterene, may also hinder folate absorption.


Form of Anemia	Description and Diagnosis	Causes and Risk Factors	Treatments
Aplastic Anemia	Bone marrow fails to produce all types of blood cells. Symptoms, in addition to standard anemia, are bleeding in mucous membranes and skin, gingivitis, higher risk for infection, and shortness of breath.	Cause is unknown in half the cases. Known causes include hereditary conditions (Fanconi's anemia), viruses (HIV, hepatitis, Epstein-Barr), autoimmune diseases (lupus, rheumatoid arthritis), medications (valproic acid, tacrolimus, azathioprine) or chemicals (benzene, pesticides).	Transfusions, antibiotics, bone marrow or stem cell transplantation, immunosuppressant drugs. (This anemia used to be nearly always fatal, but survival rates now can reach 92% with successful transplants and up to 87% with immunosuppressants.)
Thalassemia	Genetic blood disease caused by a defect in the rate of production of hemoglobin. The two major forms are thalassemia minor and thalassemia major (Cooley's anemia, beta thalassemia). Thalassemia minor is the more common and milder form, in which lifespan is normal. Thalassemia major can be serious, but it is fortunately very rare.	Affects males and females equally. Most common in people of Mediterranean descent, especially Italians and Greeks. Both types of thalassemia are found in an area that extends from northern Africa and southern Europe to Thailand, including Iran, Iraq, Indonesia, and southern China. Thalassemia major is more common in families who intermarry.	Transfusions to supply enough red blood cells to achieve moderate anemia and avoid iron overload are standard approaches for thalassemia major. Investigations are ongoing to find alternatives to transfusions. Hydroxyurea, 5-azacytidine, erythropoietin, or butyrate analogues may help some patients. Bone marrow transplantation may be needed for some types of thalassemia.
Hemolytic Anemias: Acquired	Anemia caused by hemolysis (premature destruction of red blood cells). Diagnosis considered when there is marked increase in RBC production by bone marrow.	Autoimmune hemolytic anemia is the primary type, in which antibodies produced by the immune system damage RBCs. Cause unknown or associated with disorders such as systemic lupus erythematosus, lymphoma, and paroxysmal nocturnal hemoglobinuria. Other causes are high exposure to certain metals or chemicals (lead, copper, benzene, naphthalene), snake and insect bites, malaria, transfusions, post-surgical complications, and drugs such as methyldopa. In infants, blood group incompatibility between mother and child or infections in the womb.	Corticosteroids for autoimmune hemolytic anemia. Transfusions beneficial in many cases. Various immunosuppressive drugs may be tried, as well as splenectomy. Eculizumab (Soliris) is approved for treatment of paroxysmal nocturnal hemoglobinuria.
Hemolytic Anemias: Inherited	Hemolysis (premature destruction of RBCs) caused by sphere-shaped RBCs, which have difficulties circulating through the spleen.	Inherited defects include membrane defects, hemoglobin abnormalities, and enzyme deficiencies. Fava beans may trigger symptoms. More likely and more serious in males than females.	Blood transfusions may be necessary for some types of hemolytic anemia. Experimental trials use immune globulin. Removal of the spleen (splenectomy) or bone marrow transplantation may help some patients.
Sideroblastic Anemias	Group of anemias caused by impaired ability of bone marrow to produce normal RBCs. Normal-to-high iron levels, but iron cannot be used to make hemoglobin. In addition to the standard symptoms of anemia are jaundice, enlarged liver and spleen, fever, headache, loss of appetite, vomiting, and leg sores. Symptoms can be mild. Usually appears in childhood. Infections, trauma, and pregnancy may trigger symptoms.	Inherited or acquired after excessive alcohol use, certain medications, including chloramphenicol, or other disorders, including some cancers and rheumatoid arthritis. More common in the elderly.	Deferoxamine (Desferal) is used to remove iron. Effectiveness is increased when ascorbate is added to the regimen. Folate and pyridoxine are used, but their effectiveness is under question.
Sickle Cell Anemia	Serious, life-threatening, inherited disease. The sickle-shaped, inflexible RBC has impaired ability to squeeze through vessels. Short lifespan of RBC (10-20 days) causes anemia. In addition to anemia symptoms, joint and bone pain, infections, and heart failure can occur.	Disease occurs in 0.6% and the trait is found in the genetic makeup of 9% of African-Americans. Also occurs in people from India and Spanish-speaking and Mediterranean regions.	Measures to avoid cycling and control pain. Including hydration, hydroxyurea, NSAIDs and narcotic analgesics. Bone marrow transplantation. [For information, see In-Depth Report #58: Sickle-cell disease.]

Click the icon to see an image of red blood cells found in sickle cell anemia.

Risk Factors

Although nutritional iron-deficiency anemia has declined in industrialized nations, it affects an estimated 2 billion people worldwide. Even in the U.S., iron deficiency is the most prevalent nutritional deficiency. It is highly associated with poverty. People in lower socioeconomic groups have double the risk of those who are middle or upper class.

Among Americans with iron deficiency anemia, young children have the highest risk followed by premenopausal women. Adolescent and adult men and postmenopausal women have the lowest risk. Men, in fact, are at risk for iron overload, probably because of their higher meat intake.

General Risk Factors for Anemia in Infants and Children. Up to 20% of American children and 80% of children in developing countries become anemic at some point during their childhood and adolescence. Iron deficiency is the most common cause in children, but other forms of anemia, including hereditary blood disorders, can also cause anemia in this population. Hispanic American children have double the rates of iron deficiency as African-American and Caucasian children.

Iron deficiency affects about 9% of children younger than 2 years. About 3% of children in this age group are anemic as a result. Children in lower-income homes are at higher risk than those in higher income homes. In a study of low-income children, ages 6 months to 5 years, the prevalence of anemia was over 10%, and was nearly 18% in children younger than 2 years. However, children in any income group can develop iron deficiency.

Young children 9 - 18 months have the highest risk for iron deficiency anemia in the U.S. Such children also are at great risk for problems in mental development from anemia. Infant boys may have 10 times more risk than baby girls. In general, full-term, breast-fed infants have enough iron stores for their first 6 months of life. After that, they must rely on other sources for iron.

Iron-deficiency anemia in infants and small children can be due to one or more of the following factors:

Stopping breast-feeding too early or using formula that isn't iron-fortified.
Bottle-feeding too long. Studies indicate that the longer children are bottle-fed, the greater the risk for iron-deficiency and anemia. Toddlers 12 months and older should not drink more than 2 cups of milk a day. Cow’s milk is good for children, but it does not contain enough iron. Too much milk can decrease children’s appetite and prevent them from eating the iron-rich food they need. When babies who are bottle-fed are 7 - 9 months old, they should be weaned from bottles and given sippy cups. By the age of 12 months, all children should be using a cup instead of a bottle.
Toddlers’ preferences for iron-poor food. Parents should make sure that their children eat iron-rich foods, such as beans, meat, fortified cereals, eggs, and green leafy vegetables

Better social services and more accurate ways of diagnosing and monitoring anemia are needed in these high-risk groups. There is still considerable debate on how to define iron deficiency and anemia in infants. New research suggests that a reticulocyte hemoglobin content (CHr) test may be better than a standard hemoglobin test for detecting iron deficiency in babies. Reticulocytes are immature red blood cells. The CHr test measures the amount of hemoglobin in these cells.

Up to 10% or more of adolescent and adult women under 49 years are iron deficient. Hispanic American and African-American women have double the prevalence for anemia compared to Caucasian women. The risk for anemia in adolescent girls is about 3%. Anemia is generally mild in young women, however, and is more likely to occur with one or more of the following conditions:

Heavy menstruation for longer than 5 days
Abnormal uterine bleeding, such as from fibroids
Pregnancy. About 20% of women in industrialized countries have iron deficiency during pregnancy. Multiple pregnancies and births significantly increase the risk.

Although studies have reported various estimates on the prevalence of anemia in older adults, one survey suggested that anemia affects about 10% of adults aged 65 years and older, and more than 20% aged 85 years and older. The causes of anemia in older adults were equally distributed among nutritional deficiencies, chronic inflammatory disease, chronic renal disease, and unexplained anemia. Most cases were mild.

People with alcoholism are at risk for anemia both from internal bleeding as well as folate- and vitamin B deficiency-related anemias.

Although most Americans probably consume too much iron in their diets, some people may be at risk for diet-related iron deficiencies, including:

People whose diets are high in processed foods and lack any meat.
Strict vegetarians. Vegetarians who avoid all animal products may have a slightly higher risk for deficiencies in iron and some B vitamins. Although dried beans and green vegetables often contain iron, it is less easily absorbed from plants than from meat. Fortunately, most commercial cereals are fortified with vitamin B12 and folic acid (the synthetic form of folate).

Anyone with a chronic disease that causes inflammation or bleeding is at risk for anemia. Critical illness in the intensive care unit is also highly associated with anemia.

Working out regularly may cause some iron loss, which is comparable to that from menstruation and rarely worrisome. Dietary choices may account for most cases of sports anemia. Intense, sustained exercise, such as that performed by marathon runners, may cause a condition called sports anemia, which may be due to slight gastrointestinal bleeding, damaged red blood cells, low iron intake, or poor intestinal absorption of iron.

Iron deficiency occurs in 20% of pregnant women in developed countries. Even worse, 50% or more of women in nonindustrialized nations become iron deficient, and 30 - 50% are deficient in folic acid. Severe anemia is associated with a higher mortality rate among pregnant women. Mild-to-moderate anemia, however, does not pose any elevated risk.

Pregnancy increases the risk for anemia in different ways:

It increases the body's demand for folic acid and, therefore, poses a risk for deficiencies and an increased risk for megaloblastic anemia. Low levels of folate during pregnancy increase the risk of neural tube defects in newborns.
It increases the body's demand for iron, thus posing a risk for iron deficiency anemia. Pregnant or nursing women need 30 mg of iron per day. Maternal iron deficiency anemia is associated with increased weight or size of the placenta, a condition that may later pose a risk for high blood pressure in the offspring. Pregnant women with low hemoglobin levels (the iron-bearing component in the blood) have an elevated risk for pre-term or low birth weight infants.
Pregnancy is also associated with fluid retention, which in turn may produce high volumes of plasma (the fluid component of blood). This can dilute red blood cells, which may lead to anemia.
After delivery, heavy bleeding, which occurs in 5 - 10% of women who have given birth, can cause symptoms of anemia.

Diagnosing of Iron Deficiency During Pregnancy. A diagnosis of iron deficiency is problematic in pregnant women. The standard test is a measurement of ferritin levels, which are low in most people with iron deficiency. Pregnant women, however, may have high ferritin blood levels into their third trimester but still be iron deficient. A newer test that measures a factor called serum transferrin receptor may prove to be a useful way of diagnosing iron deficiency in women. Researchers are also investigating Doppler ultrasonography as an imaging technique for detecting anemia in the fetus. Traditionally, fetal anemia is diagnosed through amniocentesis. Doppler ultrasonography is a non-invasive method that does not risk causing a miscarriage or a worsening of fetal anemia.

Preventing Anemia in Pregnant Women.

Iron Supplements. For the past 40 years, iron supplements have been recommended for all pregnant women. This practice has been challenged recently, however. There is no clear-cut evidence that the mild iron deficiency most pregnant women experience is harmful. In addition, iron supplements cause gastrointestinal side effects and may not be completely harmless. Some experts suggest iron supplements for all pregnant women whose hemoglobin levels are less than 11 g/dl, and pregnant women whose serum ferritin levels are low, beginning in their 20th - 24th weeks of pregnancy.
Vitamin Supplements. Women who are trying to conceive, who are pregnant, and who are breast-feeding should take 400 mcg of folic acid a day. They should be sure this is folic acid and not folate. Folate is the natural form of folic acid, but 400 mcg supplements of folate are half as potent as the same dose of folic acid. Pregnant and nursing women who are vegetarians should be sure to have supplements of folic acid and other B vitamins as well, since many of these nutrients are found primarily in animal products. Vitamin B12 deficiencies during pregnancy can also produce anemia in both mother and child.
Diets Rich in Vitamin C. Eating foods rich in vitamin C can help absorb iron.

Treating Anemia During Pregnancy. Pregnant women who become anemic and need treatment may be given oral iron supplements, or blood transfusions in severe cases. Intravenous or intramuscular administration of iron helps improve blood levels better than oral iron supplements, but may cause more serious side effects.

Complications

Most cases of anemia are mild, including those that occur as a result of chronic disease. Nevertheless, even mild anemia can reduce oxygen transport in the blood, causing fatigue and a diminished physical capacity. Moderate-to-severe iron-deficiency anemia is known to reduce endurance. Some studies indicate that even iron deficiency without anemia can produce a subtle but still lower capacity for exercise.

Because a reduction in red blood cells decreases the ability to absorb oxygen from the lungs, serious problems can occur in prolonged and severe anemia that is not treated. Anemia can lead to secondary organ dysfunction or damage, including heart arrhythmia and heart failure.

Certain inherited forms of anemia, including thalassemia major, pernicious anemia, and sickle-cell anemia, can be life threatening. Thalassemia major and sickle-cell anemia affect children and are particularly devastating.

Pregnant women with significant anemia may have an increased risk for poor pregnancy outcomes, particularly if they are anemic in the first trimester.

In children, severe anemia can impair growth and motor and mental development. Children may exhibit a shortened attention span and decreased alertness. Children with severe iron-deficiency anemia may also have an increased risk for stroke.

Anemia is common in older people and can have significantly more severe complications than anemia in younger adults. Some studies have reported higher mortality rates in anemic individuals 85 and older compared to their non-anemic peers. (The rates were higher in anemic men than in women.) The following are examples of its effects from different studies:

Anemia may have adverse effects on the heart and increase the severity of cardiac conditions, including reducing survival rates from heart failure and heart attacks.
Elderly people with lower levels of hemoglobin are at an increased risk of death.
Anemia may be associated with an increased incidence of falls.
Even mild anemia may possibly lead to cognitive impairment. A 2006 study of elderly women found that mild anemia worsened problem-solving abilities and other cognitive functions. Anemia may worsen an already existing dementia.

In addition to anemia, vitamin B12 deficiency can cause neurologic damage, which can be irreversible if it continues for long periods without treatment.

Anemia is particularly serious in cancer patients. In people with many common cancers, the presence of anemia is associated with a shorter survival time.

Anemia is associated with higher mortality rates and possibly heart disease in patients with kidney disease.

The combination of anemia and heart failure can increase the risk of hospitalization or death by 30 - 60%. Patients with heart failure whose hemoglobin levels decline do worse than patients with stable levels.

Blood transfusions. Patients with certain types of anemia require frequent blood transfusions. These transfusions can cause iron overload. Patients are treated with iron chelation therapy, which uses a drug that binds to iron. Excess iron is then eliminated by the kidneys. The standard drug for iron chelation therapy, deferoxamine (Desferal), is injected intravenously through an infusion pump. The treatment can be difficult for many patients. In 2005, the FDA approved a new drug, deferasirox (Exjade), to treat iron overload due to blood transfusions. Patients dilute the pills in liquid once a day and drink the mixture.

Symptoms

Symptoms of anemia vary depending on the severity of the condition. Anemia may occur without symptoms and be detected only during a medical examination that includes a blood test. When they occur, symptoms may include:

Weakness and fatigue are the most common symptoms of even mild anemia. Even iron deficiency without anemia can reduce working capacity in some people.
Shortness of breath on exertion
Rapid heartbeat
Lightheadedness or dizziness
Headache
Ringing in the ears (tinnitus)
Irritability and other mood disturbances
Pale skin (however, healthy-looking skin color does not rule out anemia if a patient has risk factors and other symptoms of anemia)
Mental confusion
Loss of sexual drive

Pica. One odd symptom, in some cases a cause of iron deficiency, is pica. This is the habit of eating unusual substances, such as ice (called pagophagia), clay, cardboard, foods that crunch, or raw starch. For example, in one study, half of people whose pica took the form of pagophagia (eating at least one tray of ice every day for 2 months) or eating foods that crunch (such as raw potatoes, carrots, or celery) were iron deficient. The pica often stops, particularly in children, when iron supplements are given. Pica is difficult to detect because patients are often ashamed to admit to such cravings.

Frequent Breath Holding. Studies have also indicated that children who hold their breath frequently when angry or upset, even to the point of fainting, may be iron-deficient. In one study, taking iron supplements reduced this phenomenon in 88% of treated children.

Symptoms of Megaloblastic Anemia. The symptoms of megaloblastic anemia from vitamin B12 or folic acid deficiencies include not only standard anemic symptoms but also:

Inflammation of the mouth (stomatitis)
Inflammation of the tongue (glossitis), which involves shrinkage at the surface and edges of the tongue

Over time, psychiatric and neurologic problems develop. Vitamin B12 deficiencies cause neurologic symptoms (numbness and tingling, depression, memory loss, and irritability), and folate deficiency may result in depression and dementia (in severe cases).

Symptoms of Pernicious Anemia. Early neurologic symptoms of pernicious anemia are due to B12 deficiency. They include numbness and tingling, depression, memory loss, and irritability. Advanced nerve damage can cause loss of balance and staggering, confusion, dementia, spasticity, loss of bladder control, and erectile dysfunction. Folic acid deficiency does not cause neurologic damage, although people with this deficiency can be irritable, forgetful, and experience personality changes. Of concern for patients with pernicious anemia and B12 deficiency anemia is that folic acid supplements can mask the presence of this disease in its early stages but not cure it. The only cure is vitamin B12 supplementation.

Diagnosis

The first step in any diagnosis is a physical examination to determine if the patient has symptoms of anemia and any complications. Because anemia may be the first symptom of a serious illness, determining its cause is very important. This may be difficult, particularly in the elderly, malnourished, or people with chronic diseases, whose anemia may be caused by one or more factors. A detailed medical, personal, and dietary history should report:

Any family or personal history of anemia
A history of gallbladder disease, jaundice, or enlarged spleen
Heavy menstrual bleeding in women
Any occurrence of blood in the stool or other signs of internal bleeding. (Even if the patient has not observed any bleeding, nonvisible blood may be present, so a rectal exam and stool test are essential.)
Any dietary history, particularly in people who are elderly, poor, or both

The doctor should examine the patient carefully, especially checking for swollen lymph nodes, an enlarged spleen, and pale skin and nail color.

Specific blood tests are given to determine anemia from any cause.

Blood and Hemoglobin Counts. A complete blood count (CBC) test is performed to determine the presence of anemia. The red blood cells, or erythrocytes, and their iron-bearing component, hemoglobin, are measured.

For example, severe anemia in adults is defined by the World Health Organization as:

Hemoglobin concentrations below 12 g/dL (7.5 mmol/L) in women. (Some evidence suggests that in older women anemia should be diagnosed at 13 g/dL and below.)
Below 13 g/dL (8.1 mmol/L) in men.

A low red blood cell (RBC) count could indicate a number of problems, including bleeding or a failure by bone marrow to manufacture red blood cells.

Hematocrit. Calculating the percentage of red blood cells in blood plasma (a measurement called the hematocrit) is also important. Plasma is the liquid portion of blood. People with a high volume of plasma may be anemic even if their blood count is normal because the blood cells have become diluted.

Normal percentages are highest in the very youngest individuals and decline as people age. They also vary by gender. The following are some examples of normal range:

Newborns: 42 - 60%
Children: 35 - 45%
Adult males: 41 - 53%
Adult women: 36 - 46%

Normal value ranges may vary slightly among different laboratories.

Smokers, people at high altitudes, and those who are dehydrated tend to have higher than normal hematocrit levels. Those at greater risk for low hematocrit levels include pregnant women and patients with cirrhosis, heart failure, and splenomegaly.

Reticulocyte Count. Reticulocytes are immature red blood cells, and their count reflects the rate of red blood cell production. The upper normal limit is about 100,000/mL. A low count, when bleeding isn't the cause, suggests problems in production in the bone marrow. An abnormally high count indicates that the red blood cells are being destroyed in high numbers and indicates hemolytic anemia. New research suggests that the reticulocyte hemoglobin content (CHr) test may be more accurate than a standard hemoglobin test for detecting iron deficiency in infants. This test may help identify babies who are at risk for becoming anemic and help them get treated earlier.

Blood Morphology. A blood smear viewed under a microscope allows an expert to classify the blood by its color, size, and shape ( morphology ). Generally red blood cells are categorized as:

Pale-colored (hypochromic) and abnormally small (microcytic)
Normal colored and normal sized (normochromic, normocytic)
Abnormally large (macrocytic)

The shape of the red blood cells, which can be distorted in many blood disorders, is also important in determining a diagnosis.

There are two steps in making a diagnosis in patients with symptoms of iron deficiency anemia:

The first step is to determine if a person is actually deficient in iron.
If iron stores are low, the second step is to diagnose the cause of the iron deficiencies, which will help determine treatment.

Determining if Iron Stores are Low. The following findings are important in determining that a person is iron deficient:

Blood cells viewed under the microscope are pale (hypochromic) and abnormally small (microcytic). They are also mostly uneven in shape. (These findings suggest iron deficiency, but they can also appear in cases of anemia due to chronic disease and thalassemia.)
Hemoglobin and iron levels are low. (These findings further suggest iron deficiency, but they can also occur in cases of anemia due to chronic disease.)
Ferritin levels are low. Ferritin is a protein that binds to iron. Low levels typically mean reduced iron stores. High ferritin levels in the blood do not always mean sufficient iron stores. For example, pregnant women may have high ferritin levels into their third trimester but still be iron deficient. Ferritin levels may also be normal or even elevated in patients with inflammation from anemia due to chronic disease, even if they also have low iron stores.
In children with iron deficiencies, reticulocytehemoglobin levels are low. Reticulocytes are immature red blood cells, and this test may be the most effective approach for diagnosing iron deficiency in children.
A test that measures a factor called serum transferrin receptor (TfR) is proving to be very sensitive in identifying iron deficiency in problematic patients, including the elderly with chronic diseases and possibly pregnant women. (It is often very difficult to identify iron deficiencies in patients who also have anemia due to chronic diseases because their ferritin levels are often normal or even high.) For example, levels of TfR are high in patients with ACD and iron deficiency anemia, but they are normal or only slightly raised in ACD alone. The test is expensive, however, and some experts recommend it should be used only when there is a high suspicion of iron deficiency in the elderly.
Measuring erythrocyte zinc protoporphyrin (ZPP), a product of abnormal heme synthesis, is under investigation and may prove to be a simple and precise measure of iron deficiencies, particularly in children.

If internal bleeding is suspected as the cause, the gastrointestinal tract is usually the first suspect as the source. A diagnosis in these cases can often be made if the patient has noticed blood in the stools, which can be black and tarry or red-streaked. Often, however, bleeding may be present but not visible. If so, stool tests for this hidden (occult ) blood are required. Additional tests may then be needed to diagnose the precipitating condition. Endoscopy, in which a fiber optic tube is used to view into the gastrointestinal tract, is helpful in many patients, particularly when the source of bleeding is unclear. A colonoscopy may also be recommended to rule out colorectal cancer.

If the patient's diet suggests low iron intake and other causes cannot be established using inexpensive or noninvasive techniques, then the patient may simply be given a monthly trial of iron supplements. If the patient fails to respond, further evaluation is needed.

Usually anemia of chronic disease is recognized during the management of the primary disease and, if the anemia is mild, additional diagnostic tests are rarely needed. The following are typical findings in ACD:

The blood cells are normal looking.
Blood tests may typically show low levels of iron in the blood, but ferritin levels are normal or even high. (Low levels of ferritin, a protein that binds to iron, indicate iron deficiency.)

Doctors need a multi-step diagnostic procedure for determining vitamin B deficiencies and the anemias that cause or are caused by them. Doctors may arrive at a diagnosis of vitamin B12 or folic acid deficiencies from different routes:

They may diagnose deficiencies after detecting megaloblastic anemia from abnormal blood tests.
They may suspect vitamin deficiencies first from symptoms and history and then look for anemia.

Diagnosing Megaloblastic Anemia. Very large oval red blood cells indicate megaloblastic anemia. Abnormally shaped neutrophils (certain white blood cells) may also be present. Bone marrow aspiration may need to be performed if the disease is strongly suspected but the diagnosis is not clear.

Determining Vitamin Deficiency. Once megaloblastic anemia has been diagnosed, the doctor will need to determine which vitamin deficiency is causing it. This is extremely important, because if a vitamin B12-deficient patient receives folate replacement only, then irreversible nerve injuries may develop. Even if blood tests for megaloblastic anemia are normal, patients with neurologic and psychiatric abnormalities that have no detectable cause should still be tested for vitamin B12 deficiency.

Often, vitamin B deficiencies cannot be determined by a history or symptoms alone. Blood tests are the primary indicators of both vitamin B12 and folic acid deficiencies, but even blood tests for these vitamins are not always straightforward:

Folic acid and vitamin B12 levels must always be measured at the same time because each vitamin may affect the other.
Folate levels may be temporarily low in some people who are not truly deficient.
Folate levels may temporarily rise in deficient people if they have just eaten foods containing the vitamin.
Antibiotics can interfere with B12 levels.

Measuring methylmalonic acid and homocysteine, substances in the blood that increase when levels of one or both vitamins are low, improves accuracy.

Tests for Pernicious Anemia. Once a vitamin B12 deficiency has been established and the doctor has not found any intestinal abnormalities or other factors to account for the deficiency, the doctor presumes a diagnosis of pernicious anemia. Pernicious anemia may also be diagnosed through various blood (such as complete blood count) or urine tests.

Pernicious anemia is treated with vitamin replacement, but the condition is easily missed, particularly in patients whose diets are rich in folic acid. Folic acid can mask the early symptoms of pernicious anemia but not cure it. Consequently the disease may persist until serious neurologic symptoms occur. With folic acid now a required additive in many commercial foods, some experts are concerned about an increased incidence in pernicious anemia.

Dietary Factors

Iron found in foods is either in the form of heme or non-heme iron:

Heme Iron. Foods containing heme iron are the best sources for increasing or maintaining healthy iron levels. Such foods include (in decreasing order of iron-richness) clams, oysters, organ meats, beef, pork, poultry, and fish.
Non-Heme Iron. Non-heme iron is less well-absorbed. About 60% of the iron in meat is non-heme (although meat itself helps absorb non-heme iron). Eggs, dairy products, and iron-containing vegetables have only the non-heme form. Such vegetable products include dried beans and peas, iron-fortified cereals, bread, and pasta products, dark green leafy vegetables (chard, spinach, mustard greens, kale), dried fruits, nuts, and seeds.

The absorption of non-heme iron often depends on the food balances in meals. The following foods and cooking methods can enhance absorption of iron:

Meat and fish not only contain heme iron -- the best form for maintaining stores -- but they also help absorb non-heme iron.
Increasing intake of vitamin-C rich foods, such as orange juice, may enhance absorption of non-heme iron, although it is not clear if it improves iron stores in iron-deficient people. In any case, vitamin-C rich foods are healthy and include broccoli, cabbage, citrus fruits, melon, tomatoes, and strawberries.
Riboflavin (vitamin B2) may help enhance the response of hemoglobin to iron. Food sources include dairy products, liver, and dried fortified cereals.
Cooking methods can enhance iron stores. Cooking in cast iron pans and skillets is well-known to increase the iron content of food. According to one study, boiling, steaming, or stir-frying in utensils composed of any material significantly increased the release of non-heme iron stored in vegetables.
Vitamins B12 and folate are important for prevention of megaloblastic anemia and for good health in general. The only natural dietary sources of B12 are animal products, such as meats, dairy products, eggs, and fish (clams and oily fish are very high in B12). As is the case with other B vitamins, however, B12 is added to commercial dried cereals. The recommended daily allowance (RDA) is 2.4 mcg a day. Deficiencies are rare in young people, although the elderly may have trouble absorbing natural vitamin B12 and require synthetic forms from supplements and fortified foods.

Click the icon to see an image of sources of vitamin B12.

Folate is best found in avocado, bananas, orange juice, cold cereal, asparagus, fruits, green, leafy vegetables, dried beans and peas, and yeast. The synthetic form, folic acid, is now added to commercial grain products. Vitamins are usually made from folic acid, which is about twice as potent as folate. Many experts now recommend that adults have 400 mcg of folic acid daily -- considerably higher than standard recommendations of 400 mcg of folate. Women who are trying to conceive, who are pregnant, and who are breast-feeding should take 400 mcg of folic acid.

Click the icon to see an image of sources of folate.

The Recommended Daily Allowance (RDA) of iron for people who are not iron deficient varies by age group and other risk factors. (Iron supplements are rarely recommended in people without evidence of iron deficiency or anemia.) The RDA recommends these daily amounts of iron:

Children 1 - 3 years old: 10 mg
Teenage boys: 12 mg
Teenage girls and premenopausal women: 15 mg
Pregnant or nursing women: 30 mg
Adult men (up to age 50): 10 mg
Older men and women (over age 50): 10 mg

The main source of iron for an infant from birth to 1 year of age is in milk, from breast milk, iron-fortified infant formula, or cereal. The best methods for preventing iron deficiency during infancy are:

Breast-feeding and Iron-Supplemented Formulas. Mothers should be encouraged to breast-feed their babies for their first year. Up to half of the iron in breast milk is absorbed by the baby and is sufficient to prevent anemia for the first 4 - 6 months, assuming that the mother had adequate iron stores during pregnancy. Breast milk itself is low in iron, but if the mother's diet is healthy, vitamin C and lactose in the breast milk may enhance iron absorption. Breast-fed babies should have iron supplements after 4 - 6 weeks, even if they are still nursing.

Infants who are not breast-fed should start with iron-fortified formulas (7-12 mg/L). Most experts strongly discourage the use of low-iron formulas (less than 4.0 mg/L). Parents should discuss the best formula with their doctor. Children given iron supplements may have a slightly higher risk for diarrhea. Experts advise against cow's milk for the first year of life. When cereals are begun, they should be iron fortified.

Recommendations for Toddlers. Toddlers who did not have iron supplements during infancy should be checked for iron deficiency. After the first year, children should be given a varied diet that is rich in sources of iron, B vitamins, and vitamin C. Milk does not contain enough iron and can decrease children's appetite for iron-rich foods. Toddlers older than 1 year should not drink more than 2 cups of milk a day. A preference for apple juice over vitamin-C rich orange juice does not reduce iron absorption in children with any otherwise healthy diet.

Treatment

Oral iron supplements are the best way to restore iron levels for people who are iron deficient, but they should be used only when dietary measures have failed. However, iron supplements cannot correct anemias that are not due to iron deficiency.

One study reported that doctors prescribed iron pills for 64% of patients with anemia, without performing tests to confirm whether iron deficiency was actually the cause. The study suggested that iron replacement was appropriate in less than half of these patients. Iron replacement therapy can cause gastrointestinal problems, sometimes severe ones. Excess iron may also contribute to heart disease, diabetes, and certain cancers. Experts generally advise against iron supplements in anyone with a healthy diet and no indications of iron deficiency anemia. However, one study suggested that supplements help reduce fatigue in women with low iron stores but no signs of anemia.

Treatment of Anemia of Chronic Disease. In general, the best treatment for anemia of chronic diseases is treating the disease itself. In some cases, iron deficiency accompanies the condition and requires iron replacement. Erythropoietin, most often administered with intravenous iron, is used for some patients.

Treatment of Megaloblastic Anemia. The standard treatments for megaloblastic anemia are vitamin B12 injections and folic acid replacement.

Supplement Forms. To replace iron, the preferred forms of iron tablets are ferrous salts, usually ferrous sulfate (Feosol, Fer-In-Sol, Mol-Iron). Other forms include ferrous fumarate (Femiron, FerroSequels, Feostat, Fumerin, Hemocyte, Ircon), ferrous gluconate (Fergon, Ferralet, Simron), polysaccharide-iron complex (Niferex, Nu-Iron), and carbonyl iron (Elemental Iron, Feosol Caplet, Ferra-Cap). Specific brands and forms may have certain advantages. The following are some examples:

Prolonged-release ferrous sulfate (Slow Fe) may enhance iron absorption with fewer side effects than standard ferrous sulfate pills.
FerroSequels contains a stool softener, which helps prevent constipation.
Polysaccharide-iron complex has fewer side effects and equal absorption rates compared to ferrous salts. It is very expensive, however.
Carbonyl iron is composed of very fine tiny uniform spheres of iron powder and may prove to be less toxic than ferrous iron.
Coated or combination pills do not appear to offer any additional advantages and may hinder absorption of the iron.

Regimen. The general guidelines for iron replacement are as follows:

For adults, doctors usually advise one ferrous sulfate tablet (300 mg) three times a day.
Iron replacement doses for children with deficiencies are significantly lower. In general, they are given as drops or syrup administered three times a day. A single-dose daily regimen is showing promise. IMPORTANT: As few as three adult iron tablets can poison children, even fatally. This includes any form of iron pill.
No one, even adults, should take a double dose of iron if one is missed.

Other tips for taking iron are as follows:

For best absorption, iron should be taken between meals. (Iron may cause stomach and intestinal disturbances, however, and some experts believe that low doses of ferrous sulfate can be taken with food and are still absorbed but with fewer side effects.)
Always drink a full 8 ounces of fluid with an iron pill. Taking orange juice with an iron pill may help increase iron absorption. (Some doctors also recommend taking a vitamin C supplement with the iron pill.)
Tablets should be kept in a cool place. (Bathroom medicine cabinets may be too warm and humid, which may cause the pills to disintegrate.)

Full recovery takes 6 - 8 weeks. Recovery will take longer in people with internal bleeding that is not under control. Iron replacement therapy must continue for about 6 months, even if anemia has been reversed. Treatment must be continued indefinitely for people with chronic bleeding; in such cases, iron levels should be closely monitored.

Side Effects. Common side effects of iron supplements include the following:

Constipation and diarrhea are very common. They are rarely severe, although iron tablets can aggravate existing gastrointestinal problems such as ulcers and ulcerative colitis.
Nausea and vomiting may occur with high doses, but can be controlled by taking smaller amounts. Switching to ferrous gluconate may help some people with severe gastrointestinal problems.
Black stools are normal when taking iron tablets. In fact, if they do not turn black, the tablets may not be working effectively. This tends to be a more common problem with coated or long-acting iron tablets.
If the stools are tarry looking as well as black, if they have red streaks, or if cramps, sharp pains, or soreness in the stomach occur, gastrointestinal bleeding may be causing the iron deficiency and the patient should call the doctor promptly.
Acute iron poisoning is rare in adults but can be fatal in children who take adult-strength tablets.

Interactions with Other Drugs. Certain medications, including antacids, can reduce iron absorption. Iron tablets may also reduce the effectiveness of other drugs, including the antibiotics tetracycline, penicillamine, and ciprofloxacin and the Parkinson's disease drugs methyldopa, levodopa, and carbidopa. At least 2 hours should elapse between doses of these drugs and iron supplements.

Supplements. The following vitamin and mineral supplements may improve iron absorption:

Adding either ascorbic acid (vitamin C) or succinic acid to ferrous sulfate therapy will improve absorption of iron stores.
Some studies have found that the addition of zinc to iron supplements increases hemoglobin levels more than iron alone. Some evidence for this suggests that zinc affects a hormone called insulin-like growth factor-I (IGF-I), which plays a role in the regulation of red blood cell production.

In some cases, iron is administered through muscular injections or intravenously. Intravenous iron has the advantage of causing less gastrointestinal discomfort and inconvenience. It may be in the form of iron dextran (Dexferrum, InFed), sodium ferric gluconate complex in sucrose (Ferrlecit), or iron sucrose (Venofer). Ferrlecit or Venofer are proving to be at least equally effective and safer than iron dextran.

Candidates. The injected or intravenous forms should be limited to the following patients with iron deficiency:

People with iron deficiency anemia in whom oral therapy has clearly failed.
Patients with bleeding disorders in which blood loss continues to exceed the rate at which oral iron is absorbed.
In emergencies, when people need red blood cells but transfusion is not appropriate or available.
In people with serious gastrointestinal disorders, such as inflammatory bowel disease, who cannot take iron therapy by mouth.
People undergoing hemodialysis who receive supplemental erythropoietin therapy. Sodium ferric gluconate complex in sucrose (Ferrlecit) or iron sucrose (Venofer) is specifically approved as first-line therapy for these patients.

Certain patients, even if they meet these qualifications, may not be appropriate candidates or should be monitored closely for complications. They include:

Patients with any underlying autoimmune disease.
Malnourished patients who also have an underlying infection.
Patients who are at risk for iron overload.

Side Effects. Some side effects differ depending on how the iron is administered and include the following:

Muscular injections include pain at the site.
Intravenous administration can cause pain in the vein, flushing, and metallic taste, all of which are brief.

For both methods, side effects and serious complications can include:

Blood clots
Fever
Joint aches
Headache
Rashes
A delayed reaction of joint and muscle aches, headache, and malaise occurs 1 - 2 days after the infusion (most commonly with iron dextran) in about 10% of patients. These symptoms respond quickly to NSAIDs, such as ibuprofen or naproxen, in most people.
Iron toxicity. Symptoms include nausea, dizziness, and a sudden drop in blood pressure. Sodium ferric gluconate in sucrose (Ferrlecit) or iron sucrose (Venofer) may pose a lower risk for toxicity than iron dextran.
Allergic reactions. Allergic reactions that occur with intravenous iron can be very serious and, in rare cases, even fatal. Iron dextran appears to pose a much higher risk than sodium ferric gluconate complex in sucrose or iron sucrose, although allergic reactions can also occur with the latter forms.

Oral and injected iron should never be given at the same time. Intravenous iron therapy may be appropriate for some pregnant women who meet these requirements, depending on the pregnancy term and other factors.

Transfusions are used to replace blood loss due to injuries and during certain surgeries. They are also commonly used to treat severely anemic patients who have thalassemia, sickle cell disease, myelodysplastic syndromes, or other types of anemia. Some patients require frequent blood transfusions. Iron overload can be a side effect of these frequent blood transfusions. If left untreated, iron overload can lead to liver and heart damage.

Iron chelation therapy is used to remove the excess iron caused by blood transfusions. Patients take a drug that binds to the iron in the blood. The excess iron is then removed from the body by the kidneys. For many years, deferoxamine (Desferal) was the only drug used in chelation therapy. This drug is usually injected intravenously, using an infusion pump. The infusion can last 8 - 12 hours and may be needed 5 - 7 days a week until iron levels are normal. A new drug, deferasirox (Exjade), was approved in 2005 for children and adults as a once-daily treatment for iron overload due to blood transfusions. It does not require injections. Patients mix the deferasirox tablets in liquid and drink the medicine. Doctors hope that this new drug may make it easier for patients to tolerate chelation therapy. Studies have shown that deferasirox works as well as deferoxamine in ridding the body of excess iron.

Bloodless Medicine. Bloodless medicine and surgery is a new field designed to reduce or minimize blood loss and transfusions. It also attempts to address the problems in treating certain religious groups, such as Jehovah's Witnesses, who refuse transfusions. Some techniques involved in this field include new surgical procedures or drugs that minimize blood loss, the use of erythropoietin, volume expanders (administration of fluids to dilute blood), using tiny blood samples for testing, and methods (Cell Saver) for recovering and recycling blood during surgery.

Erythropoietin is the hormone that acts in the bone marrow to increase the production of red blood cells. It has been genetically engineered as recombinant human erythropoietin (rHuEPO) and is available as epoetin alfa (Epogen, Procrit, and Eprex). Novel erythropoiesis stimulating protein (NESP), also called darbepoetin alfa (Aranesp), lasts longer in the blood than epoetin alfa and requires fewer injections. These medications are also called “erythropoiesis-stimulating drugs.”

Levels of erythropoietin are reduced in anemia of chronic disease. Injections of synthetic erythropoietin can help increase the number of red blood cells in order to avoid receiving blood transfusions. Erythropoietin is used to treat anemia. It does not help improve anemia symptoms, fatigue, or quality of life for patients with cancer or HIV. This drug can cause serious side effects, including blood clots, and is approved only for treating patients with anemia related to the following conditions:

Cancer. For select patients, erythropoietin is used to treat the anemia associated with chemotherapy.
Chronic kidney failure. Erythropoietin is an important anemia treatment for patients with chronic kidney failure, including those on dialysis.
HIV/AIDS. Erythropoietin helps treat the anemia caused by zidovudine (AZT) therapy.

In November 2007, the Food and Drug Administration (FDA) made major changes to the prescribing information for erythropoiesis-stimulating drugs. The new labels describe in detail the risks that Aranesp, Epogen, and Procrit can pose to patients with cancer and chronic kidney disease. The FDA has also established separate dosing recommendations for each of these conditions.

Erythropoiesis-Stimulating Drugs and Cancer. Erythropoietin should be used only to treat anemia caused by chemotherapy -- not anemia due to other causes in patients with cancer. Erythropoietin treatment does not help prolong survival. In fact, these drugs can shorten survival time and cause tumors to grow faster. Discuss with your doctor whether an erythropoiesis-stimulating drug is appropriate for you.

Survival and tumor growth risks are especially pronounced for patients with advanced breast, head and neck, lymphoid, or non-small cell lung cancer when dosing attempts to achieve a hemoglobin level of 12 g/dL or greater. However, there may be similar risks for patients dosed to less than 12 g/dL. (The American Society of Clinical Oncology and the American Society of Hematology recommend starting erythropoietin when a patient’s hemoglobin level falls to less than 10 g/dL.) The doctor should use the lowest effective dose and erythropoietin treatment should be stopped as soon as the chemotherapy course is completed.

Erythropoiesis-Stimulating Drugs and Chronic Kidney Failure. For patients with chronic kidney failure, the FDA recommends that erythropoiesis-stimulating drugs be used to maintain hemoglobin levels between 10 - 12 g/dL. (The exact level within this range varies by individual.) There is a greater risk of death and serious cardiovascular events, such as heart attack, stroke, and heart failure when these drugs are used to achieve higher hemoglobin levels (13.5 - 14g/dL) compared to lower hemoglobin levels (10- 11.3 g/dL).

Warning Symptoms. Contact your doctor if you experience any of the following symptoms while being treated with an erythropoiesis-stimulating drug:

Pain or swelling in the legs
Worsening in shortness of breath
Increases in blood pressure (be sure to regularly monitor your blood pressure)
Dizziness or loss of consciousness
Extreme fatigue
Blood clots in hemodialysis vascular access ports

H. pylori, the bacteria that cause peptic ulcers, is associated with anemias from vitamin B12 deficiency and iron deficiency. People whose anemia is associated with H. pylori infection, however, do not respond to iron therapy. Studies indicate that the eradication of H. pylori infection with antibiotics can reverse anemia in such patients and may lead to long-lasting recovery.

Vitamin B12 Therapy. Injections of vitamin B12 (usually formulations called cyanocobalamin or hydroxocobalamin), oral folic acid therapy, or both, rapidly reverse the production of abnormally large red blood cells. (Treatments still may not reverse neurologic symptoms if they are extensive or have continued for too long.)

A typical regimen for vitamin B12 replacement is as follows:

If diagnostic tests indicate pernicious anemia and neurologic symptoms are present, vitamin B12 therapy should begin immediately. (Usually vitamin therapy is not an emergency, however.)
Cyanocobalamin or hydroxocobalamin injections are given every day for up to 2 weeks. Only small doses are needed.
This is followed by injections twice a week for another month. (Hemoglobin levels rise in the first week of therapy and reach normal levels in 8 weeks.)
After that, injections are usually given monthly.
During recovery, there is a risk of potassium deficiency as the new red cells take up the existing supply, so potassium supplements may be needed.

Other forms of vitamin B12 are also available and can be used to treat B12 deficiency. Vitamin B12 nasal spray offers the same advantage of avoiding the need for absorbing the vitamin in the GI tract without the inconvenience of the injections. Some experts feel that even oral B12 in high doses (2,000 mcg/day) can maintain B12 levels once the deficiency is treated.

The injections are safe and have no adverse side effects, but they may mask an underlying medical or psychological condition.

Some doctors give vitamin B12 injections for fatigue and other vague symptoms of general mild discomfort. In one study, 10% of patients in a rural clinic were given regular B12 shots, with 6% of patients having no medical need for them.

Folic Acid Treatment. Folate deficiency is easily remedied in 4 - 5 weeks with daily oral doses of 1 - 2 milligrams of folic acid. Many doctors give vitamin B12 along with folic acid unless B12 deficiency is definitely ruled out.

Resources

www.anemia.org -- National Anemia Action Council
www.nhlbi.nih.gov -- National Heart, Lung and Blood Institute
www.irondisorders.org -- Iron Disorders Institute
www.thalassemia.org -- Cooley's Anemia Foundation
www.aamds.org -- Aplastic Anemia & MDS International Foundation
http://kidney.niddk.nih.gov/kudiseases/pubs/anemia -- National Kidney and Urologic Diseases Clearinghouse (Anemia in kidney disease and dialysis)

References

Brotanek JM, Gosz J, Weitzman M, Flores G. Iron deficiency in early childhood in the United States: risk factors and racial/ethnic disparities. Pediatrics. 2007 Sep;120(3):568-75.

Killip S, Bennett JM, Chambers MD. Iron deficiency anemia. Am Fam Physician. 2007 Mar 1;75(5):671-8.

Komajda M, Anker SD, Charlesworth A, et al. The impact of new onset anaemia on morbidity and mortality in chronic heart failure: results from COMET. Eur Heart J. 2006 Jun;27(12):1440-6. Epub 2006 May 22.

KDOQI. KDOQI Clinical Practice Guideline and Clinical Practice Recommendations for anemia in chronic kidney disease: 2007 update of hemoglobin target. Am J Kidney Dis. 2007 Sep;50(3):471-530.

Maguire JL, deVeber G, Parkin PC. Association between iron-deficiency anemia and stroke in young children. Pediatrics. 2007 Nov;120(5):1053-7.

Martí-Carvajal AJ, Solà I. Treatment for anemia in people with AIDS. Cochrane Database Syst Rev. 2007 Jan 24;(1):CD004776.

Notebaert E, Chauny JM, Albert M. Short-term benefits and risks of intravenous iron: a systematic review and meta-analysis. Transfusion. 2007 Oct;47(10):1905-18.

Reveiz L, Gyte GM, Cuervo LG. Treatments for iron-deficiency anaemia in pregnancy. Cochrane Database Syst Rev. 2007 Apr 18;(2):CD003094.

Rizzo JD, Somerfield MR, Hagerty KL, et al. Use of epoetin and darbepoetin in patients with cancer: 2007 American Society of Clinical Oncology/American Society of Hematology Clinical Practice Guideline Update. J Clin Oncol. 2007 Dec 21 [Epub ahead of print]

Review Date:
1/1/2008
Reviewed By:
Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M. Copyright

adam.com

Restless legs syndrome and related disorders

FitSugar — Wed, 08 Oct 2008 17:35:14 -0700

In This Report

Highlights
Introduction
Causes
Risk Factors
Complications
Diagnosis
Treatment
Medications
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Treatment

The American Academy of Sleep Medicine recommends medications for restless legs syndrome (RLS) or periodic limb movement disorder (PLMD) only for persons who fulfill strict diagnostic criteria and experience too much daytime sleepiness as a result of these conditions. (Excessive daytime sleepiness results from nighttime sleeplessness due to RLS or PLMD symptoms).
The U.S. Food and Drug Administration (FDA) announced in March 2007 that the dopamine agonist drug pergolide (Permax) has been voluntarily withdrawn from the market. This drug can cause serious damage to the heart valves of patients who take it.
The FDA approved pramipexole (Mirapex) for use in moderate-to-severe restless legs syndrome (RLS) in November 2006.
Bupropion (Wellbutrin), a newer antidepressant, may also be helpful for RLS. Bupropion, a weak dopamine reuptake inhibitor, causes a slight increase in the availability of dopamine in the brain. It is not addictive and does not have the severe side effects of other RLS drugs, but more research is needed to determine its usefulness. It is not FDA approved for RLS.

Research

Results from a large study show that RLS is more common in children and teens than epilepsy and diabetes. The study also found that more than 70% of affected children had at least one biological parent with RLS.
Two recently-published studies found an abnormal gene on chromosome 6 makes some people susceptible to RLS and PLMD.
People with type 2 diabetes have higher rates of secondary RLS. Nerve pain (neuropathy) related to their diabetes cannot fully explain this increased rate in RLS.

Introduction

Restless legs syndrome (RLS) is an unsettling and poorly understood movement disorder affecting 3 - 15% of the general population. RLS can affect both children and adults. Although effective treatments are available, the condition often remains undiagnosed.

Symptoms of RLS. The core symptom of RLS is an irresistible urge to move the legs (medically known as akathisia). Some people describe this symptom as a sense of unease and weariness in the lower leg, which is aggravated by rest and relieved by movement. Specific characteristics of RLS include:

"Pulling, searing, drawing, tingling, bubbling, or crawling" beneath the skin, usually in the calf area, causing an irresistible urge to move the legs. These sensations can occur not only in the lower legs, but they can also affect the thighs, feet, and even the upper body. RLS-type symptoms may also occur in the arms. This may be the first symptom of RLS in some people.
About 80% of patients with RLS also experience semi-rhythmic movements called periodic limb movement disorder (PLMD).
Itching and pain, particularly aching pain, may be present.
Patients experience symptoms when they feel most relaxed and their legs are at rest. (Movement, however, brings relief.) Symptoms usually occur at night when lying down, or sometimes during the day while sitting.
Episodes of RLS usually develop between 10 p.m. and 4 a.m. Symptoms are often most severe shortly after midnight. They typically occur for 30 - 60 seconds, and they usually resolve by morning. If the condition becomes more severe, people may begin to have symptoms during the day. These symptoms are always worse at night, however.
At night, the unpleasant sensations and the resulting uncontrollable urge to move the legs can often disturb sleep. Ignoring the need to move the legs usually only builds up tension until they jerk uncontrollably. If patients experience symptoms during the day, they usually feel compelled to move their legs in order to relieve the symptoms, making it difficult to sit during air or car travel or through classes or meetings.

Late-onset and Early-onset Forms. There appear to be two forms of RLS, early-onset and late-onset. Each form may have different characteristics:

People with early-onset RLS (occurring in the teenage years or earlier) tend to have a family history of the disorder. They also usually have RLS without accompanying pain.
Those with late-onset RLS usually do not have a family history of RLS. Their condition is more likely the result of a problem with the nervous system, and symptoms may include pain in the lower legs.

The medical term for periodic limb movement disorder (PLMD) is nocturnal myoclonus. PLMD symptoms include:

Episodes that usually occur during the night, peaking near midnight, as they do in restless legs syndrome (RLS).
Leg muscles contract and jerk every 20 - 40 seconds during sleep. Such movements may last less than 1 second, or as long as 10 seconds.
Unlike RLS, contractions in PLMD usually do not wake patients. PLMD is distinct from the brief and sudden movements that occur just as people are falling asleep, jolting them awake.

Although 80% of RLS sufferers have PLMD, only about 30% of people with PLMD also have RLS. While treatments for the two conditions are similar, PLMD is a separate syndrome. PLMD is also very common in narcolepsy, a sleep disorder that causes people to fall asleep suddenly and uncontrollably.

Cramps that awaken people during sleep are very common, and they are not part of restless legs syndrome or periodic limb movement disorder. They can be very painful and may cause a person jump out of bed in the middle of the night. They typically affect a specific area of the calf or the sole of the foot.

Circadian Rhythm. In sleep studies, subjects spend about one-third of their time asleep, suggesting that most people need about 8 hours of sleep each day. However, individual adults differ in the amount of sleep they need to feel well rested. Infants may sleep as many as 16 hours a day.

The daily cycle of life, which includes sleeping and waking, is called a circadian rhythm (circadian means "about a day"), or the biological clock. Hundreds of bodily functions follow biologic clocks, but sleeping and waking comprise the most prominent circadian rhythm. The sleeping and waking cycle is about 24 hours long. If confined to windowless apartments, with no clocks or other time cues, sleeping and waking only as their bodies dictate, humans typically live on slightly longer than 24-hour cycles.

The circadian rhythm usually takes the following daily patterns:

Humans prefer daytime activity and nighttime rest.
A natural peak in sleepiness occurs at mid-day, the traditional siesta time.
Daily rhythms interact with other factors that may interfere or change individual patterns:
- The fraction-of-a-second-firing of nerve cells in the brain may be faster or slower in different individuals.
- The monthly menstrual cycle in women can shift the pattern.

Light signals coming through the eyes reset the circadian cycles each day, so changes in season, or changes in exposures to light and dark, can unsettle the pattern.

The Response in the Brain to Light Signals. The brain's response to light signals is an important key factor in sleep:

Light signals travel to a tiny cluster of nerves in the hypothalamus (in the center of the brain). This cluster is the body's master clock, which is called the supra chiasmatic nucleus (SCN). The SCN is named for its location, which is just above (supra) the optic chiasm, a major junction where nerves transmit information about light from the eyes.
The approach of dusk each day prompts the SCN to signal the nearby pineal gland (named so because it resembles a pinecone) to produce the hormone melatonin.
Researchers think that melatonin acts as the body's time-setting hormone. It also appears to trigger the need to sleep. The longer a person is in darkness, the longer the duration of melatonin secretion. Staying in bright light can decrease the secretion of melatonin.

Sleep consists of two distinct states that alternate in cycles, and reflect differing levels of brain nerve cell activity:

Non-Rapid Eye Movement Sleep. Non-rapid eye movement (NREM) sleep is also called quiet sleep. NREM is further subdivided into three stages of progression:

Stage 1: Light sleep
Stage 2: "True" sleep
Stage 3 to 4: Deep "slow-wave" or delta sleep

With each ascending stage, awakening becomes more difficult. It is not clear what governs NREM sleep in the brain. A balance between certain hormones, particularly growth and stress hormones, may be important for deep sleep.

Rapid Eye-Movement Sleep. Rapid eye-movement (REM) sleep is also called active sleep. Most vivid dreams occur in REM sleep. Brain activity in REM sleep is comparable to that in waking, but the muscles are virtually paralyzed, possibly preventing people from acting out their dreams. Except for vital organs like the lungs and heart, the only muscles not paralyzed during REM sleep are the eye muscles. REM sleep may be critical for learning and for day-to-day mood regulation. When people are sleep-deprived, their brains must work harder than when they are well rested.

The REM/NREM Cycle. The cycle between quiet and active sleep generally follows this pattern:

After about 90 minutes of NREM sleep, eyes move rapidly behind closed lids, giving rise to REM sleep.
As sleep progresses the NREM/REM cycle repeats.
With each cycle, NREM sleep becomes progressively lighter, and REM sleep becomes progressively longer, lasting from a few minutes early in sleep to perhaps an hour at the end of the sleep cycle.

The hypothalamus is a highly complex structure in the brain that regulates many important brain chemicals. Malfunction of this area of the brain may give rise to cluster headaches.

Causes

The main cause of restless legs syndrome (RLS) is unknown. Researchers are investigating neurologic (nervous system) problems that may arise either in the spinal cord or the brain. One current theory suggests that a deficiency in a brain chemical called dopamine causes restless legs syndrome.

RLS may often have a genetic basis, particularly in those who develop it before age 40. When the condition occurs in older adults, it is most likely due to a neurological problem.

The central nervous system is comprised of the brain and spinal cord. The peripheral nervous system includes all peripheral nerves.

People with restless legs syndrome (RLS) often have a family history of the disorder. Researchers have detected specific genetic locations or factors that might be responsible for this condition. Much of the research comes from studies of families with a strong history of RLS-related conditions. In 2005, researchers linked a location on chromosome 12 to RLS. They named this genetic marker RLS1. Locations on chromosomes 14 and 9 may also be associated with hereditary forms of RLS.

Dopamine and Neurologic Abnormalities in the Brain. Some research suggests that neurologic abnormalities involved with restless legs syndrome (RLS) and periodic limb movement disorder (PLMD) start in the brain. A variety of studies support the theory that an imbalance in neurotransmitters (chemical messengers in the brain), notably dopamine and serotonin, may play a part in RLS. Dopamine and serotonin cause numerous nerve impulses that affect muscle movement. The effect is similar to what happens in Parkinson's disease. Moreover, drugs that increase dopamine levels treat both disorders. However, Parkinson's disease itself does not seem to increase the risk for RLS. Nor does RLS early in life predispose to Parkinson's later on.

Neurologic Abnormalities in the Spine. Other research suggests that restless legs syndrome may be due to nerve impairment in the spinal cord. Researchers considered that such abnormalities were likely to start in nerve pathways in the lower spine. However, some patients with RLS have symptoms in the arms, indicating that the upper spine may also be involved.

Neuropathy. Some experts suggest that RLS, particularly if it occurs in older adults, may be a form of neuropathy, which is an abnormality in the nervous system outside the spine and brain. Nevertheless, there is no evidence of a causal relationship.

Iron deficiency, even at a level too mild to cause anemia, has been linked to restless legs syndrome (RLS) in some people. Studies suggest, in fact, that RLS in some people may be due to a problem with getting iron into cells that regulate dopamine in the brain. Some studies have reported RLS in 25 - 30% of people with low iron levels. The common connection between RLS and Parkinson's disease, in turn, may be not having enough iron in these patients.

The cause or causes of periodic limb movement disorder (PLMD) are not clear. Some research suggests that it may be due to abnormalities in the autonomic nervous system, which regulates the involuntary actions of the smooth muscles, heart, and glands.

Risk Factors

Restless legs syndrome (RLS) may affect 2.5 - 15% of the general population. It is more common in women than in men, and its frequency increases with age. The disorder affects an estimated 10 - 28% of adults older than age 65. In about 40% of patients, RLS begins in adolescence.

RLS may be more common than epilepsy and diabetes in children and teens. More than 70% of affected children in one study had at least one biological parent with RLS.

As many as two-thirds of people with restless legs syndrome (RLS) have a family history of the disorder. If so, RLS is more likely to occur before they turn 40. (A family history of RLS is less likely in people who develop it as older adults.) RLS is also more common in people from northern and western Europe, giving added support for a genetic basis for some cases.

Restless legs syndrome (RLS) and periodic leg movement disorder (PLMD) in children are strongly associated with inattention and hyperactivity. One study suggested that a quarter of children diagnosed with attention-deficit hyperactivity disorder (ADHD) also have RLS or PLMD, and this may actually contribute to inattentiveness and hyperactivity. The disorders have much in common, including poor sleep habits, twitching, and the need to get up suddenly and walk about frequently. Some evidence suggests that the link between the diseases may be a deficiency in the brain chemical dopamine.

About 20% of pregnant women report having restless legs syndrome (RLS). The condition usually goes away about a month after delivery. RLS in this population has been strongly associated with deficiencies in iron and the B vitamin folate.

Between 20 - 62% of people undergoing dialysis report restless legs syndrome. Symptoms often disappear after a kidney transplant.

Anxiety can cause restlessness and agitation at night. These symptoms can cause (or strongly resemble) restless legs syndrome.

The following medical conditions are also associated with restless legs syndrome (RLS), although the relationships are not clear. In some cases, these conditions may contribute to RLS, or they may have a common cause. In some cases, they may coexist due to other risk factors:

Osteoarthritis (degenerative joint disease). About 72% of patients with RLS also have osteoarthritis, a common type of arthritis affecting mostly older adults.
Varicose veins. Varicose veins occur in 14% of patients with RLS. Sclerotherapy treatments, in which doctors inject medications into affected veins, may relieve symptoms in such cases.
Obesity
Diabetes -- people with type 2 diabetes may have higher rates of secondary RLS. Nerve pain (neuropathy) related to their diabetes cannot fully explain this increased rate in RLS.
Hypertension
Hypothyroidism (a condition in which the thyroid gland does not make enough hormones)
Fibromyalgia (chronic pain of unknown cause)
Rheumatoid arthritis
Emphysema (a lung disease usually caused by smoking)
Chronic alcoholism
Sleep apnea (pauses in breathing during sleep) and snoring
Chronic headaches
Brain or spinal injuries

Many muscle and nerve disorders. Hereditary ataxia, a group of genetic diseases that affects the central nervous system and causes loss of motor control, is of particular interest. Researchers believe that hereditary ataxia may supply clues to the genetic causes of RLS.

Osteoarthritis is a chronic disease of the joint cartilage and bone, often thought to result from "wear and tear" on a joint, although there are other causes such as congenital defects, trauma, and metabolic disorders. Joints appear larger, are stiff and painful, and usually feel worse the more they are used throughout the day.

Click the icon to see an image of hypothyroidism.

Click the icon to see an image of fibromyalgia.

Click the icon to see an image of rheumatoid arthritis.

Click the icon to see an image of emphysema.

Several environmental and dietary factors can worsen or provoke restless legs syndrome (RLS):

Iron deficiencies. People who are deficient in iron are at risk for restless legs syndrome, even if they do not have anemia
Folic acid or magnesium deficiencies
Smoking
Alcohol abuse
Caffeine (coffee drinking is specifically associated with PLMD)
Stress
Fatigue
Prolonged exposure to cold

Drugs that worsen or provoke the condition include:

Antidepressants
Antipsychotic drugs
Anti-nausea drugs
Beta-blockers (a type of heart medication)
Antihistamines
Oral decongestants
Diuretics
Asthma drugs
Spinal anesthesia (anesthesia-induced restless legs syndrome typically disappears on its own within several months)

About 6% of the general population has periodic limb movement disorder (PLMD). Among the elderly, the prevalence increases to 25 - 58%. Studies suggest that PLMD may be especially common in elderly women. As with RLS, numerous conditions are associated with PLMD. They include sleep apnea, spinal cord injuries, stroke, narcolepsy, and diseases that destroy nerves or the brain over time. Certain medications, including some antidepressants and anti-seizure medications, may also contribute to PLMD.

Complications

Restless legs syndrome rarely results in any serious consequences. But in some cases, severe and persistent symptoms can cause considerable mental distress, chronic insomnia, and daytime sleepiness.

Sleep deprivation, and the daytime sleepiness that follows, is increasingly recognized as a cause of mood disruption and a contributor to industrial errors and motor vehicle crashes.

Effect on Daily Performance and Activities. Studies suggest that sleeplessness worsens many waking behaviors. These include:

Reduced concentration. Deep sleep deprivation appears to impair the brain's ability to process information.
Impaired task performance. Missing several hours of nightly sleep over the course of a week can negatively affect performance levels and mood. In fact, sleep deprivation can cause impaired performance levels comparable to those of intoxicated people.
Effect on learning. Whether sleeplessness significantly impairs learning is unclear. Some studies have reported problems in memorization, although others have found no differences in test scores between people with temporary sleep loss and those with full sleep.

In addition, since restless legs syndrome (RLS) is worse when resting, people with severe RLS may avoid daily activities that involve long periods of sitting, such as going to movies or traveling long distances.

Studies in Swedish working-aged men and women reported that those with restless legs syndrome (RLS) were more apt to be socially isolated, to have frequent daytime headaches or depression, and to complain of reduced libido or problems related to sleepiness.

RLS can contribute to insomnia. Insomnia itself can increase the activity of hormones and pathways in the brain that produce emotional problems. Even modest alterations in waking and sleeping patterns can have significant effects on a person's mood. Persistent insomnia may even predict the future development of mood disorders in some cases.

It is not clear if RLS is responsible for negative mood states or if anxiety or depression contributes to RLS. Anxiety can cause agitation and leg restlessness that resemble RLS, and depression and RLS symptoms also overlap. In addition, certain types of antidepressant drugs -- such as serotonin reuptake inhibitors -- can increase periodic limb movements during sleep.

Diagnosis

A diagnosis of restless legs syndrome or nocturnal leg cramps often relies solely on the patient's description of symptoms. In general, the recommended approach is first to take a sleep and personal history. The doctor may conduct an interview that includes the following questions:

How would you describe your sleep problem?
How long have you had this sleep problem?
How long does it take you to fall asleep?
How many times a week does the problem occur?
How restful is your sleep?
What are the leg problems like (cramps, twitching, crawling feelings)?
What is your sleep environment like? Noisy? Not dark enough?
What medications are you taking (including the use of antidepressants and self-medications -- such as herbs, alcohol, and over-the-counter or prescription drugs)?
Are you taking or withdrawing from stimulants, such as coffee or tobacco?
How much alcohol do you drink per day?
What stresses or emotional factors may be present in your life?
Have you experienced any significant life changes?
Do you snore or gasp during sleep? (This may be an indication of sleep apnea. Sleep apnea is a condition in which breathing stops for short periods many times during the night. It may worsen symptoms of restless legs syndrome or insomnia.)
If you have a bed partner, does he or she notice that you have jerking legs, interrupted breathing, or thrashing while you sleep?
Are you a shift worker?

Keeping a Record of Sleep. To help answer these questions, the patient may need to keep a sleep diary. Every day for 2 weeks, the patient should record all sleep-related information, including responses to questions listed above described on a daily basis. Recording sleep behavior using an extended-play audio or videotape can be very helpful in diagnosing sleep apnea.

A bed partner can help by adding their observations of the patient's sleep behavior.

Some high-risk patients may need to consult a sleep specialist or go to a sleep disorders center before their sleep problem can be diagnosed. At most centers, patients undergo an in-depth analysis, usually supervised by a team of consultants from various specialties, who can provide both physical and psychiatric evaluations. Centers should be accredited by the American Academy of Sleep Medicine.

Among the signs that may indicate a need for a sleep disorders center are:

Insomnia due to psychological disorders
Sleeping problems due to substance abuse
Snoring and sudden awakening with gasping for breath (possible sleep apnea)
Severe restless legs syndrome
Persistent daytime sleepiness
Sudden episodes of falling asleep during the day (possible narcolepsy)

Overnight polysomnography involves several tests to measure different functions during sleep. It is typically performed in a sleep center and may help rule out sleep apnea or confirm the effectiveness of restless legs syndrome (RLS) treatments.

The patient arrives about 2 hours before bedtime without having made any changes in daily habits. Polysomnography electronically monitors the patient as he or she passes, or fails to pass, through the various sleep stages. Polysomnography tracks the following:

Brain waves
Body movements
Breathing
Heart rate
Eye movements
Changes in breathing and blood levels of oxygen

Actigraphy uses a small wristwatch-like device (such as Actiwatch) to monitor sleep quality in people with suspected restless legs syndrome (RLS), periodic leg movement disorder (PLMD), insomnia, sleep apnea, and other sleep-related conditions. Patients can wear the device on their wrists or ankles. It measures and records muscle movements during sleep. For example, with PLMD, actigraphy can provide information on the total duration of movements, the number of occurrences, whether PLMD occurs simultaneously in both legs, and its effects on sleep.

Actigraphy is not as accurate as polygraphy because it cannot measure all the biological effects of sleep. It is more accurate than a sleep log, however, and very helpful for recording long periods of sleep.

The Epworth sleepiness scale uses a simple questionnaire to measure excessive sleepiness during eight situations.


Situation	Chance of Dosing
Sitting and reading	(Indicate a score of 0 to 3) 0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing
Watching TV	(Indicate a score of 0 to 3) 0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing
Sitting inactive in a public place	(Indicate a score of 0 to 3) 0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing
Riding as a passenger in a car for an hour without a break	(Indicate a score of 0 to 3) 0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing
Lying down to rest in the afternoon when circumstances permit	(Indicate a score of 0 to 3) 0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing
Sitting and talking to someone	(Indicate a score of 0 to 3) 0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing
Sitting quietly after a lunch without alcohol	(Indicate a score of 0 to 3) 0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing
Sitting in a car while stopped for a few minutes in traffic	(Indicate a score of 0 to 3) 0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing
Score Results 1-6: Getting enough sleep. 4-8: Tends to be sleepy but is average. 9 and over: Very sleepy and suggestive of sleep-disordered breathing. Patient should seek medical advice.

Because of the high association between restless legs syndrome and iron deficiency, a test for low iron stores should be part of the diagnostic workup in restless legs syndrome (RLS). There are two steps in making this diagnosis:

The first step is to determine if a person is actually deficient in iron.
If iron stores are low, the second step is to diagnose the cause of the iron deficiencies, which will help determine treatment.

Determining if Iron Stores are Low: The following findings are important in determining that a person is iron deficient:

Blood cells viewed under the microscope are pale (hypochromic) and abnormally small (microcytic). They are also mostly uneven in shape. These findings suggest iron deficiency, but they can also appear in anemia resulting from chronic disease and in thalassemia.
Hemoglobin and iron levels are low. These findings further suggest iron deficiency, but they can also occur in cases of anemia due to chronic disease.
Ferritin levels are low. Ferritin is a protein that binds to iron, and low levels typically mean the patient does not have enough iron in their body. However, high levels of ferritin in the blood do not always mean a patient has enough iron. For example, pregnant women may have high ferritin levels even in their third trimester, yet still be iron deficient. Ferritin levels may also be normal, or even elevated, in patients with inflammation resulting from anemia due to chronic disease, even if these patients also so not have enough iron in their body.
A test that measures a factor called serum transferrin receptor (TfR) is proving to be very sensitive in identifying iron deficiency in some patients, including the elderly with chronic diseases and possibly pregnant women.

Determining Causes of Iron Deficiency. When iron deficiency anemia is diagnosed, the next step is to determine what causes the iron deficiency itself.

Dietary iron deficiency is most common in children and infants. It is rare in adults.
Heavy menstrual or abnormal uterine bleeding is usually the cause of iron deficiencies in young women. Increased need for iron during pregnancy is also a common cause of iron deficiency in pregnant women.
If doctors suspect internal bleeding as the cause of iron deficiency, they look first to the digestive tract as the possible source. A diagnosis in such cases can often be made if the patient has noticed blood in their stools, (the stool would be black and tarry or red-streaked). Often, however, bleeding may be present but not visible. In such cases, stool tests for this hidden (occult) blood are required. The patient may need additional tests to diagnose the cause of bleeding. One common test is endoscopy, in which a fiberoptic tube is used to look into the gastrointestinal tract. Doctors recommend it particularly when the source of bleeding is unclear.

If the patient's diet suggests low iron intake and doctors cannot find other causes of iron deficiency, they may recommend a month-long trial of iron supplements. If the patient fails to respond, they will need further evaluation.

Certain laboratory tests may be helpful in determining causes of restless legs syndrome (RLS) or conditions that rule it out. They include:

Blood glucose tests for diabetes
Tests for kidney problems
In certain cases, tests for thyroid hormone, magnesium, and folate levels

In addition to other sleep-related leg disorders, a number of other medical conditions may have features that resemble restless legs syndrome (RLS). The doctor will need to consider these disorders in making a diagnosis.

Peripheral Neuropathies. Peripheral neuropathies are nerve disorders in the hands or feet. Several conditions can cause these disorders, and they can produce pain, burning, tingling, or shooting sensations in the arms and legs. Diabetes is a very common cause of painful peripheral neuropathies. Other causes include alcoholism, rheumatoid arthritis, systemic lupus erythematosus, amyloidosis, HIV infection, kidney failure, and certain vitamin deficiencies. Symptoms of peripheral neuropathies may mimic RLS. However, unlike RLS, they are not usually associated with restlessness, movement does not relieve the discomfort, and they do not worsen at bedtime.

Deep Vein Thrombosis. Deep vein thrombosis (DVT) is a blood clot in a deep vein in the body, usually in the leg. It may cause pain, swelling, and aching in the leg where the clot has developed. It can occur in people with heart disease, with varicose veins, during pregnancy, in women from hormonal treatments, from injury to the leg, or from inactivity (such as after surgery or during long flights). In women, it can also result from hormonal treatments. Left untreated, DVT can be a very serious and even life-threatening condition.

This picture shows a red and swollen thigh and leg caused by a blood clot (thrombus) in the deep veins in the groin (iliofemoral veins), which prevents normal return of blood from the leg to the heart.

Intermittent Claudication and Peripheral Artery Disease. Peripheral artery disease (PAD) occurs when atherosclerosis (commonly called hardening of the arteries) affects the feet and legs. In such cases, blocked arteries reduce the flow of oxygen-rich blood to the legs or feet. Intermittent claudication is an important symptom of PAD and occurs in between one-third and one-half of these patients. The word claudication describes the pain that occurs in PAD patients when they exercise, particularly when they walk. In intermittent claudication, blood flows only enough to meet the needs of the person at rest. The result is leg pain during exercise, which disappears during rest.

Click the icon to see an image of peripheral artery disease.

Akathisia. Akathisia is a state of restlessness or agitation, and feelings of muscle quivering. A condition called hypotensive akathisia is caused by failure in the autonomic nervous system. Unlike RLS, it occurs at any time of the day and usually only when the patient is sitting -- not lying down. Drugs used to treat schizophrenia and other psychoses can cause akathisia, as can anti-nausea drugs. The condition also occurs when drugs to treat Parkinson's disease are withdrawn.

Painful Legs and Moving Toes Syndrome. A rare disorder affecting one or both legs, painful legs and moving toes syndrome is marked by a constant, deep, throbbing ache in the limbs and involuntary toe movements. The discomfort may be mild or severe. It gets worse with activity and usually stops during sleep. Usually, the cause is unknown, though it may arise from spinal injuries or herpes zoster infection. The condition is difficult to treat, although the drug baclofen, combined with either clonazepam or carbamazepine, has shown some success. Other treatments that may help include orthotics for the shoes and transcutaneous electrical nerve stimulation (TENS).

Meralgia Paresthetica. An uncommon nerve condition, meralgia paresthetica causes numbness, pain, tingling, or burning on the front and side of the thigh. It usually occurs on one side of the body, and the cause may be compression of the thigh nerve as it passes through the pelvis. It typically occurs in people aged 30 - 60 years, but it can affect people of all ages. It often goes away on its own.

Treatment

The first step in treating a patient who complains of sleeplessness and restless legs syndrome is to try to improve sleep and eliminate possible causes of restless legs syndrome (RLS). Doctors normally try to achieve these goals without the use of drugs, initially. A non-drug approach is a particularly important first step for elderly patients.

The doctor should first try to treat any underlying medical conditions that may be causing restless legs.
If medications may be causing RLS, the doctor should try to prescribe alternatives, if possible.

If the cause cannot be determined, it is best to first try better sleep habits and relaxation methods. These approaches may help, even if the patient needs drug therapy later on.

Some people report help or relief from restless legs syndrome (RLS) with the following behaviors or devices:

Hot baths or cold compresses help some patients.
Ergonomic measures -- for example, patients might find it useful to work at a high stool, where they can dangle their legs. In meetings or during air travel, it is helpful to have an aisle seat.
Changing sleep patterns -- some patients report that symptoms do not occur if they sleep late in the morning. Therefore, if feasible, patients can try changing sleep patterns.
Avoiding caffeine, alcohol, and nicotine also improves some cases of RLS.

Some patients recommend alternative treatments for RLS, such as acupuncture and massage. To date, however, there is not enough data on the effectiveness of these treatments.

Some people have reported benefits from:

Vitamin E (800 - 1,200 IU per day)
Calcium, magnesium, or potassium supplements
Folic acid supplements for people with folate deficiencies

Folate (folic acid) is necessary for the production of red blood cells and for the synthesis of DNA (which controls heredity and is used to guide the cell in its daily activities). Folic acid also helps with tissue growth and cell function. In addition, it helps to increase appetite when needed and stimulates the formation of digestive acids.

Because restless legs syndrome (RLS) is associated with iron insufficiency, people with the condition should get enough iron from their diet. [See In-Depth Report #57: Anemia.] Iron is found in foods either in the form of heme or non-heme iron:

Foods containing heme iron are the best for increasing or maintaining healthy iron levels. Such foods include (in decreasing order of iron-richness) clams, oysters, organ meats, beef, pork, poultry, and fish.
Non-heme iron is less well absorbed. About 60% of the iron in meat is non-heme (although meat itself helps absorb non-heme iron). Eggs, dairy products, and iron-containing vegetables (including dried beans and peas) have only the non-heme form. Other sources of non-heme iron include iron-fortified cereals, bread, and pasta products, dark green leafy vegetables (chard, spinach, mustard greens, kale), dried fruits, nuts, and seeds.

The Effects of Food on Iron Absorption. The absorption of non-heme iron often depends on the food balances in meals. The following are foods that enhance absorption of non-heme iron.

Meat and fish not only contain heme iron, the best form for maintaining stores, but they also help absorb non-heme iron.
Eating more vitamin C-rich foods can enhance absorption of non-heme iron during a single meal. In any case, vitamin C-rich foods are healthy. They include broccoli, cabbage, citrus fruits, melon, tomatoes, and strawberries. One orange or 6 ounces of orange juice can double the amount of iron your body absorbs from plant foods. (Taking vitamin C supplements does not appear to have any significant effect on how much iron your body stores.)
Foods containing riboflavin (vitamin B2) may help enhance the formation of hemoglobin from iron. Sources include liver, dried fortified cereals, and yogurt.

Certain nutrients impede the body's absorption of dietary iron. They include:

Polyphenols (found in tea, coffee, red wine, berries, and apples)
Phytates (found in foods such as seeds, dried beans, soy, and bran). Such foods are typically high in fiber. It is often believed that fiber itself impedes iron absorption, but researchers report that it has little or no effect.
Calcium. Calcium impairs the absorption of heme and non-heme iron. However, calcium intake must be quite high to cause any significant problems.

The Effects of Cooking Methods on Iron. Cooking methods can enhance the amount of iron in your body. Cooking in cast iron pans and skillets is a well-known way to increase the iron content of food. According to one study, boiling, steaming, or stir-frying in utensils composed of any material significantly increased the release of non-heme iron stored in vegetables.

Iron supplements can significantly reduce symptoms in people with restless legs syndrome (RLS) who are also iron deficient. Patients should use them only when dietary measures have failed. Iron supplements do not appear to be useful for RLS patients with normal or above normal iron levels.

Prolonged-release ferrous sulfate (Slow Fe) may enhance iron absorption with fewer side effects than standard ferrous sulfate pills.
FerroSequels contains a stool softener, which helps prevent constipation.
Polysaccharide-iron complex has fewer side effects and equal absorption rates compared to ferrous salts. It is very expensive, however.
Carbonyl iron is composed of very fine tiny uniform spheres of iron powder and may prove to be less toxic than ferrous iron.
Coated or combination pills do not appear to offer any additional advantages and may hinder absorption of the iron.

Regimen. A reasonable approach for patients with RLS is to take 65 mg of iron (or 325 mg of ferrous sulfate) along with 100 mg of vitamin C on an empty stomach, 3 times a day.

IMPORTANT: As few as 3 adult iron tablets can poison, and even kill, children. This includes any form of iron pill. No one, not even adults, should take a double dose of iron if they miss one dose.

Tips for taking iron are:

For best absorption, take iron between meals. (Iron may cause stomach and intestinal disturbances, however. Some experts believe that you can take low doses of ferrous sulfate with food and avoid the side effects.)
Always drink a full 8 ounces of fluid with an iron pill.
Keep tablets in a cool place. Bathroom medicine cabinets may be too warm and humid, which may cause the pills to disintegrate.

Side Effects. Common side effects of iron supplements include the following:

Constipation and diarrhea -- these are rarely severe, although iron tablets can aggravate existing digestive problems such as ulcers and ulcerative colitis.
Nausea and vomiting may occur with high doses, but you can control this by taking smaller amounts. Switching to ferrous gluconate may help some people with severe digestive problems.
Black stools are normal when taking iron tablets. In fact, if they do not turn black, the tablets may not be working effectively. This tends to be a more common problem with coated or long-acting iron tablets.
If the stools are tarry looking as well as black, if they have red streaks, or if cramps, sharp pains, or soreness in the stomach occurs, bleeding in the digestive tract may be causing the iron deficiency, and the patient should call the doctor immediately.
Acute iron poisoning is rare in adults, but can be fatal in children who take adult-strength tablets.

Interactions With Other Drugs. Certain medications, including antacids, can reduce iron absorption.

Iron tablets may also reduce the effectiveness of other drugs, including:

Antibiotics: tetracycline, penicillamine, and ciprofloxacin
Anti-Parkinson's disease drugs: methyldopa, levodopa, and carbidopa

At least 2 hours should elapse between doses of these drugs and doses of iron supplements.

Supplementary Treatments. The following supplements may improve iron absorption:

Adding either ascorbic acid (vitamin C) or succinic acid to ferrous sulfate treatment will improve absorption of iron stores. Ascorbic acid added to iron treatment, however, may worsen some of the side effects. Succinic acid added to ferrous sulfate does not appear to increase side effects.
Some studies have found that the addition of zinc to iron supplements increases hemoglobin levels more than iron alone. Some evidence suggests that zinc affects a hormone called insulin-like growth factor-I (IGF-I), which plays a role in the regulation of red blood cell production.

Exercise earlier in the day may be one of the best ways to achieve healthy sleep. However, vigorous exercise and stimulation (including sexual activity) within 1 - 2 hours of bed time may worsen restless legs syndrome (RLS). A study found that people who walked briskly for 30 minutes, four times a week, improved minor sleep disturbances after 4 months. Regular, moderate exercise, healthful in any case, may help prevent RLS. Patients report that either bursts of excessive energy or long sedentary periods worsen symptoms.

Benign nocturnal leg cramps, sometimes known as a charley horse, are muscle spasms in the calf that can occur one or many times during the night. Cramping may also occur in the soles of the feet. They typically last from a few seconds to a few minutes. Some people experience them regularly, others only on isolated occurrences.

Causes of Nocturnal Leg Cramps. In most cases, the cause of nocturnal leg cramps remains unknown. Among the conditions that might cause leg cramps are:

Calcium and phosphorus imbalances, particularly during pregnancy
Low potassium or sodium (salt) levels
Overexertion, standing on concrete for long periods, or prolonged sitting (especially with the legs contorted)
Having structural disorders in the legs or feet (such as flat feet)
Medical causes of muscle cramping include hypothyroidism, Addison's disease, uremia, hypoglycemia, anemia, and certain medications. Various diseases that affect nerves and muscles, such as Parkinson's, cause leg cramps. Peripheral neuropathy, a complication of diabetes, can cause cramp-like pain, numbness, or tingling in the legs. Patients with kidney disease undergoing dialysis are also prone to leg cramps.

Individuals at Higher Risk for Nocturnal Leg Cramps. Nocturnal leg cramps occur at all ages but peak at different times. They are particularly common in adolescence, during pregnancy, and in older age, affecting up to 70% of adults over age 50 at some point.

Pregnant women and those taking diuretics are also at risk for leg cramps because of low calcium levels and an imbalance in calcium and phosphorus.

Consequences of Nocturnal Leg Cramps. Nocturnal leg cramps, like restless legs syndrome, rarely have any serious consequences. However, they can be extremely painful and long lasting. In some cases, severe and persistent symptoms can cause chronic insomnia and considerable mental distress.

Managing Nocturnal Leg Cramps. Once a cramp begins, straighten the leg, flex the foot upward toward the knee, or grab the toes and pull them toward the knee.

Walking or shaking the affected leg, then elevating it, may also help.

If soreness persists, a warm bath or shower or an ice pack may bring relief.

Lifestyle Tips for Preventing Nocturnal Leg Cramps. Nighttime leg cramps are generally treated with lifestyle changes.

Everyone with leg cramps should drink plenty of water (at least 6 - 8 glasses daily) to maintain adequate fluid levels.
Pregnant women and others who get legs cramps due to low calcium levels should reduce milk intake, because drinking milk does not correct the underlying imbalances in calcium and phosphorus. Instead, they should boost calcium levels by taking nonphosphate calcium supplements.
To prevent cramps from occurring, nightly stretching exercises may be the best preventive measure. Patients should stand about 30 inches from a wall and, keeping the heels flat on the floor, lean forward and slowly move the hands up the wall to achieve a comfortable stretch. A few minutes on a stationary bicycle at bedtime may also help.
While in bed, loose covers should be used to prevent the toes and feet from pointing, which causes calf muscles to contract and cramp. Propping the feet up higher than the torso may also help.
During the week, swimming and water exercises are a good way to keep muscles stretched, and wearing supportive footwear is also important.

Quinine. Quinine had been widely used to prevent leg cramping. The U.S. Food and Drug Administration (FDA) banned its sale over the counter because it reportedly caused some serious, although rare, side effects. These side effects include bleeding problems and heart irregularities. Other, less serious side effects include headaches, vision problems, and rash.

The FDA has since banned the marketing of most quinine drugs, cautioning against the off-label (non-approved) use of the drug to treat RLS. Only one form of the drug, Qualaquin, is approved for sale, for the treatment of some types of malaria. Pregnant women and those with liver problems should avoid quinine in any form.

Supplements. Some small studies indicate that the mineral magnesium, taken as magnesium citrate or magnesium lactate, may provide some benefit to people with leg cramps, including pregnant women.

In one small study, taking vitamin B complex was helpful. Other supplements tried for leg cramps include vitamin E, calcium, and potassium or sodium chloride, but these do not appear to be very effective. Sodium chloride (salt) may be helpful, but Western diets already contain too much sodium.

Medications

The American Academy of Sleep Medicine recommends medications for restless legs syndrome (RLS) or periodic limb movement disorder (PLMD) only for persons who fit strict diagnostic criteria, and who experience excessive daytime sleepiness as a result of these conditions. (Excessive daytime sleepiness results from nighttime sleeplessness due to RLS or PLMD symptoms). Little is known about the best way to treat RLS, but some experts suggest the following:

Over-the-counter pain relievers and possibly mineral and vitamin supplements (particularly folic acid in people who might be deficient) should be the first form of treatment.
People with RLS should have a test for iron deficiency. If they are iron deficient, they should start treatment with iron supplements.
Dopaminergic drugs (drugs that increase levels of dopamine) are the standard medicines for treating severe RLS, PLMD, or both.
Other drugs may be helpful if dopaminergic drugs fail, or for patients who have frequent -- but not nightly -- symptoms. These include opiates (pain relievers), benzodiazepines (sedative hypnotic drugs), or anticonvulsants. However, benzodiazepines and opiates can become habit forming and addictive.

Before taking stronger medications, people should try over-the-counter pain relievers, such as acetaminophen (Tylenol) or non-steroidal anti-inflammatory drugs (NSAIDs), which include ibuprofen (Advil, Motrin, Rufen), naproxen (Anaprox, Naprosyn, Aleve), and ketoprofen (Orudis KT, Aktron).

Although NSAIDs work well, long-term use can cause stomach problems, such as ulcers and bleeding, and possible heart problems. In April 2005, the Food and Drug Administration asked drug manufacturers of NSAIDs to include a warning label on their product that alerts users of an increased risk for heart-related problems and digestive tract bleeding.

Dopaminergic drugs increase the availability of the chemical messenger dopamine in the brain, and are the first-line treatment for severe restless legs syndrome (RLS) and periodic leg movement disorder (PLMD). These drugs significantly reduce the number of limb movements per hour, and improve the subjective quality of sleep. Patients with either condition who take these drugs have experienced up to 100% reduction in symptoms.

Dopaminergic drugs, however, can have severe side effects (they are ordinarily used for Parkinson's disease). They do not appear to be as helpful for RLS related to dialysis as they do for RLS from other causes.

Dopaminergic drugs include dopamine precursors and dopamine receptor agonists.

Dopamine Precursors. The dopamine precursor levodopa (L-dopa) was once a popular drug for severe RLS. The standard preparations (Sinemet, Atamet) combine levodopa with carbidopa, which improves the action of levodopa and reduces some of its side effects, particularly nausea. Levodopa can also be combined with benserazide (Madopar) with similar results, but Sinemet is almost always used in America. (Levodopa combinations are well tolerated and safe.)

Patients typically start with a very low dose taken 1 hour before bedtime. The dosage is increased until the patient finds relief. Patients sometimes need to take an extended form or to take it again during the night.

Levodopa acts fast, and the treatment is usually effective within the first few days of therapy. One study reported that a combination therapy of regular-release L-dopa plus sustained release L-dopa was effective in improving sleep.

Serious common side effects of L-dopa treatment (and, to lesser extent, of dopamine receptor agonists) are augmentation and rebound. Many studies report that augmentation (worsening of symptoms that occur earlier in the day) occurs in up to 70% of patients who take L-dopa. The risk is highest for patients who take daily doses, especially doses at high levels (greater than 200 mg/day). For this reason, patients should use L-dopa only intermittently (fewer than 3 times per week). The drug should be immediately discontinued if augmentation does occur. Following withdrawal from L-dopa, patients can switch to a dopamine receptor agonist.

The rebound effect causes increased leg movements at night or in the morning as the dose wears off, or as tolerance to the drug builds up.

Dopamine Receptor Agonists. Dopamine receptor agonists (also called dopamine agonists) mimic the effects of dopamine by acting on dopamine receptors in the brain. They are now generally preferred to L-dopa. Because they have fewer side effects than L-dopa, including rebound effect and augmentation, these drugs may be used on a daily basis. (Rebound effect is the worsening of symptoms over time; augmentation means the appearance of symptoms earlier in the day. About 30% of patients who take dopamine receptor agonists have reported augmentations symptoms. As the newer drugs are taken for longer periods and at higher doses, however, their augmentation rates may become closer to those of L-dopa.)

Dopamine agonists have been shown to relieve symptoms in 70 - 90% of patients. Dopamine agonists can be ergot-derived (such as cabergoline) or non-ergot derived (such as pramipexole and ropinirole). The newer non-ergotamine derivatives may induce fewer side effects than ergot-derived drugs. Studies on these medications report the following:

Ropinirole (Requip) is a non-ergotamine dopamine agonist. Approved in 2005, ropinirole is the first drug approved specifically for treatment of moderate-to-severe RLS (more than 15 RLS episodes a month). Side effects are generally mild but may include nausea, vomiting, drowsiness, and dizziness.
The Food and Drug Administration (FDA) approved pramipexole (Mirapex) for use in moderate-to-severe RLS in November 2006. However, patients may fall asleep, without warning, while taking this drug, even while performing activities such as driving.

Cabergoline (Dostinex) is also showing promise in clinical trials. In one study, cabergoline was used for RLS after levodopa had either failed or resulted in increased symptoms. Patients in the study reported relief or freedom from symptoms after 4 weeks of use. A 2006 study indicated that a single evening dose of cabergoline improved both day and nighttime limb movements, and sleep disturbances.The FDA announced in March 2007 that the dopamine agonist pergolide (Permax) was voluntarily withdrawn from the market. Studies confirmed that this drug could cause serious damage to the heart valves of patients who take it. These problems have not been reported with ropinirole or pramipexole, which are chemically different then pergolide.

Other Dopamine Agonists. Rotigotine is a unique dopamine agonist that is being developed in patch form for RLS. In May 2007, the FDA approved this patch for treatment of early Parkinson's disease. Other dopamine agonists that have shown some promise in small studies include alpha-dihydroergocryptine, or DHEC (Almirid), and piribedil (Trivastal).

Regimens. The effects of L-dopa are apparent in 15 - 30 minutes. Dopamine receptor agonists, meanwhile, take at least 2 hours to start working. Some doctors recommend regular use of dopamine receptor agonists for patients who experience nightly symptoms, and L-dopa for those whose symptoms occur only occasionally.

Side Effects. Common side effects of dopaminergic drugs vary but may include feeling faint or dizzy (especially when standing up), headaches, abnormal muscle movements, rapid heartbeat, insomnia, bloating, chest pain, and dry mouth. Nausea may be especially common. Adding the drug domperidone may help to relieve this side effect. In rare cases, dopaminergic drugs can cause hallucinations or lung disease.

Because these drugs may cause daytime drowsiness, patients should be extremely careful while driving or performing tasks that require concentration.

Long-term use of dopaminergic drugs can lead to loss of effectiveness (tolerance). Adding a drug called entacapone (Comtan) may prolong the duration of action of carbidopa-levodopa therapy (Sinemet), but it can cause nausea.

Rebound effect, augmentation, and tolerance can reduce the value of dopaminergic drugs in the treatment of RLS. Using the lowest dose possible can minimize these effects.

Withdrawal Symptoms. Patients who withdraw from these drugs typically experience very severe RLS symptoms for the first 2 days after stopping. RLS eventually returns to pre-treatment levels after about a week. The longer a patient uses these drugs, the worse their withdrawal symptoms.

Benzodiazepines, such as clonazepam (Klonopin), are known as sedative hypnotics. Doctors prescribe them for insomnia and anxiety. They may be helpful for some patients with restless legs syndrome (RLS) that disrupts sleep. Clonazepam may be particularly helpful for children with both periodic limb movement disorder and symptoms of attention deficit hyperactivity disorder. The medicine also may be helpful for patients with RLS who are undergoing dialysis.

Side Effects. Elderly people are more susceptible to side effects. They should usually start at half the dose prescribed for younger people, and should not take long-acting forms. Side effects may differ depending on whether the benzodiazepine is long-acting or short-acting.

The drugs may increase depression, a common condition in many people with insomnia.
Breathing problems may occur with overuse or in people with pre-existing respiratory illness.
Long-acting drugs have a very high rate of residual daytime drowsiness compared to others. They have been associated with a significantly increased risk for automobile accidents and falls in the elderly, particularly in the first week after taking them. Shorter-acting benzodiazepines do not appear to pose as high a risk.
There are reports of memory loss (so-called traveler's amnesia), sleepwalking, and odd mood states after taking triazolam (Halcion) and other short-acting benzodiazepines. These effects are rare and probably enhanced by alcohol.
Because benzodiazepines cross the placenta and enter breast milk, pregnant and nursing women should not use them. There are some reports of an association between the use of benzodiazepines in the first trimester of pregnancy and the development of cleft lip in newborns. Studies are conflicting at this point, but, due to other known side effects of benzodiazepines, pregnant women should not use these drugs, if possible.
In rare cases, overdoses have been fatal.

Interactions. Benzodiazepines are potentially dangerous when used in combination with alcohol. Some drugs, such as the ulcer medication cimetidine, can slow the breakdown of benzodiazepine.

Withdrawal Symptoms. Withdrawal symptoms usually occur after prolonged use and indicate dependence. They can last 1 - 3 weeks after stopping the drug and may include:

Gastrointestinal distress
Sweating
Disturbed heart rhythm
In severe cases, patients might hallucinate or experience seizures, even a week or more after they stop taking the drug.

Rebound Insomnia. Rebound insomnia, which often occurs after withdrawal, typically includes 1 - 2 nights of sleep disturbance, daytime sleepiness, and anxiety. The chances of rebound are higher with the short-acting benzodiazepines than with the longer-acting ones.

Narcotics are pain-relieving drugs that act on the central nervous system. They are sometimes prescribed for severe cases of restless legs syndrome (RLS). They may be a good choice if pain is a prominent feature. Some evidence also suggests that narcotics reduce the frequency of periodic leg movements.

There are two types of narcotics, both of which have been used for severe RLS:

Opiates (such as morphine and codeine) come from natural opium. Some patients report relief with the use of the opiate fentanyl (Duragesic), available in skin patch form. An implanted pump that uses morphine and an anesthetic called bupivacaine is showing promise for patients with severe RLS. The pump delivers the drugs to the fluid surrounding the spinal cord (cerebrospinal fluid).
Opioids are synthetic drugs. The most common example is oxycodone (Percodan, Percocet, Roxicodone, Oxycontin). Apomorphine is a morphine derivative. In one study, when injected under the skin at night, it reduced nocturnal discomfort and leg movements in some patients.

Although the use of narcotics for severe RLS is controversial, some studies have suggested that even when the treatments are long-term, they are rarely addictive for pain sufferers except among patients with a history of substance abuse.

The use of such drugs may be beneficial when included as part of a comprehensive pain management program. Such a program involves screening prospective patients for possible drug abuse, and regularly monitoring those who are taking narcotics. Doses should be adjusted as necessary to achieve an acceptable balance between pain relief and side effects. Patients on long-term opiate therapy should also be monitored periodically for sleep apnea, a condition that causes breathing to stop for short periods many times during the night. Sleep apnea may worsen symptoms of RLS, insomnia, and other complaints.

Tramadol. Tramadol (Ultram) is a pain reliever that has been used as an alternative to opioids. In one study, tramadol was very effective for RLS and produced few or no side effects. It has opioid-like properties, but is not as addictive. (However, there are reports of dependence and abuse with this drug as well.) Withdrawal after long-term use (longer than a year) can cause intense symptoms, including diarrhea, insomnia, and even restless legs syndrome itself.

Antiseizure drugs -- such as gabapentin (Neurontin), valproic acid (valproate, divalproex, Depakote, Depakene), and carbamazepine (Tegretol) -- relax blood vessels and are being tested for restless legs syndrome (RLS). Gabapentin, a newer antiseizure drug, is showing particular promise for mild-to-moderate RLS. One study reported that it improved RLS symptoms and sleep, particularly in patients who also experienced pain. It was also effective for periodic leg movement disorder. A new gabapentin product is in phase III clinical trials for the treatment of RLS. The new drug, known as XP13512, converts to gabapentin in the intestines, and therefore may reduce some of the side effects experienced by patients taking antiseizure medications.

Side Effects. All antiseizure drugs have potentially severe side effects. Therefore, patients should try these medications only after non-drug methods have failed. Side effects of many anti-seizure drugs include nausea, vomiting, heartburn, increased appetite with weight gain, hand tremors, irritability, and temporary hair thinning and hair loss (taking zinc and selenium supplements may help reduce this last effect). Some antiseizure drugs can also cause birth defects and, in rare cases, liver toxicity. Gabapentin may have fewer of these side effects than valproic acid or carbamazepine.

Antidepressants. Bupropion (Wellbutrin), a newer antidepressant, may be helpful for restless legs syndrome (RLS). Bupropion is a weak dopamine reuptake inhibitor -- it causes a slight increase in the availability of dopamine in the brain. The drug is not addictive and does not have the severe side effects of other RLS drugs, but more research is needed to determine if it is useful.

Clonidine. Clonidine (Catapres), a drug used for high blood pressure, is helpful for some patients and may be an appropriate choice for patients who have RLS accompanied by hypertension. It also may help patients with RLS who are undergoing hemodialysis.

Baclofen. The anti-spasm drug baclofen (Lioresal) appears to reduce intensity of RLS (although not frequency of movements).

Resources

www.aasmnet.org -- American Academy of Sleep Medicine
www.sleepfoundation.org -- National Sleep Foundation
www.ninds.nih.gov -- National Institute of Neurological Disorders and Stroke
www.nhlbi.nih.gov/about/ncsdr/ -- National Center on Sleep Disorders Research
www.rls.org -- Restless Legs Syndrome Foundation
www.wemove.org -- Worldwide Education and Awareness for Movement Disorders

References

Bogan RK, Fry JM, Schmidt MH, Carson SW, Ritchie SY. Ropinirole in the treatment of patients with restless legs syndrome: a US-based randomized, double-blind, placebo-controlled clinical trial. Mayo Clin Proc. 2006 Jan;81(1):17-27.

Claman DM; Redline S; Blackwell T, Ancoli-Israel S, Surovec S, Scott N, et al. Prevalence and correlates of periodic limb movements in older women. J Clin Sleep Med. 2006 Oct;2(4):438-445.

Merlino G, Fratticci L, Valente M, et al. Association of restless legs syndrome in type 2 diabetes: a case-control study. Sleep. 2007; 30(7): 866-71.

Oertel WH, Benes H, Bodenschatz R, Peglau I, Warmuth R, Happe S, et al. Efficacy of cabergoline in restless legs syndrome: a placebo-controlled study with polysomnography (CATOR). Neurology. 2006 Sep 26;67(6):1040-6.

Partinen M, Hirvonen K, Jama L, Alakuijala A, Hublin C, Tamminen I, et al. Efficacy and safety of pramipexole in idiopathic restless legs syndrome: a polysomnographic dose-finding study--the PRELUDE study. Sleep Med. 2006 Aug;7(5):407-17.

Picchietti D, Winkelman JW. Restless legs syndrome, periodic limb movements in sleep, and depression. Sleep. 2005 Jul 1;28(7):891-8.

Picchietti D. Restless legs syndrome: prevalence and impact in children and adolescents--the Peds REST study. Pediatrics. 2007; 120(2): 253-66.

Stefansson H, Rye DB, Hicks A, et al. A Genetic Risk Factor for Periodic Limb Movements in Sleep. N Engl J Med. 2007;357:639-47.

Winkelman JW, Sethi KD, Kushida CA, Becker PM, Koester J, Cappola JJ, et al. Efficacy and safety of pramipexole in restless legs syndrome. Neurology. 2006 Sep 26;67(6):1034-9.

Winkelmann J, Schormair B, Lichtner P, et al. Genome-wide association study of restless legs syndrome identifies common variants in three genomic regions. Nat Genet (in press). [cited in: Winkelmann J. Periodic Limb Movements in Sleep - Endophenotype for Restless Legs Syndrome? N Engl J Med. 2007; 357:703-05.]

Review Date:
10/22/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Weight control and diet

FitSugar — Wed, 08 Oct 2008 17:34:58 -0700

In This Report

Highlights
Introduction
Biological and Medical Caus...
Cultural and Emotional Caus...
Risk Factors
Complications
Weight Loss and Maintenance...
Weight Management
Medications
Other Treatments
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Cancer and Weight Control:

Cancer prevention guidelines from the American Cancer Society stress the importance of maintaining a healthy weight throughout life. A healthy weight is even more important than eating specific healthy foods, when it comes to cancer prevention.

Drug Warning:

The US Food and Drug Administration (FDA) is warning consumers not to buy a product known as the "Brazilian diet pill." This product is labeled as a dietary supplement, but contains several chemicals found in powerful prescription drugs. The products are also known as Emagrece Sim and Herbathin dietary supplements.

New Over-the-Counter Medication:

In February 2007, the FDA approved the first over-the-counter (OTC) weight-loss drug. Orlistat, previously available only by prescription as Xenical, will be available OTC at half its prescription strength. It will be sold under the name alli. Those eager to use the new pill should consider its cost and modest benefits compared with its side effects, most commonly oily diarrhea. This pill, which prevents fat absorption from food, also increases the risk of not absorbing important nutrients from food while using it. The FDA recommends taking a daily multivitamin supplement when using alli.

Research News:

A small study in Norway found that a diet low in fat and high in carbohydrates ("carbs") increases symptoms of psychological distress, such as depression and anger. The study compared three different diets with varying amounts of fat and carbohydrates.
A study released in March 2007 found that obesity in young girls results in early puberty -- as early as age 9.

Effects of Obesity on the Body:

Obesity is associated with certain problems related to infertility, such as uterine fibroids or menstrual irregularities. In men, obesity can contribute to reduced testosterone levels.
People who are obese are at higher risk for carpal tunnel syndrome and other problems involving nerves in their wrists and hands.
The Pickwickian syndrome, named for an overweight character in a Dickens novel, occurs in severe obesity when lack of oxygen produces intense and chronic sleepiness and, eventually, heart failure.

Introduction

A stable weight depends on a good balance between the energy you get from food and the energy you use. You use energy during the day in three ways:

As energy expended during rest (basal metabolism)
As energy used to break down food (thermogenesis)
As energy used during physical activity

Basal metabolism accounts for about two-thirds of spent energy. Your body generally uses this energy to keep your body temperature steady and keep the muscles of your heart and intestine working. Thermogenesis accounts for about 10% of spent energy.

When a person consumes more calories than the energy they use, the body stores the extra calories in fat cells. Fat cells function as energy reservoirs. They enlarge or shrink depending on how people use energy. If people do not balance energy input and output by eating right and exercising, fat can build up. This can lead to weight gain.

When energy input is equal to energy output, there is no expansion of fat cells (lipocytes) to accommodate excess. It is only when more calories are taken in than used that the extra fat is stored in the lipocytes and the person begins to accumulate fat.

Obesity is determined by measuring body fat, not just body weight. People might be over the weight limit for normal standards, but if they are very muscular with low body fat, they are not obese. Others might be normal or underweight, but still have excessive body fat. The following measurements and factors are used to determine whether or not a person is overweight to a degree that threatens their health:

Body mass index (BMI) (a measure of body fat)
Waist circumference (size around the waist)
Waist-hip ratio
Skin fold measurement (anthropometry)
The presence or absence of other disease risk factors (e.g., smoking, high blood pressure, unhealthy cholesterol levels, diabetes, relatives with heart disease)

A person's disease risk factors plus BMI may be the most important components in determining health risks with weight.

The Body Mass Index (BMI). The current standard measurement for obesity is the body mass index (BMI). In general, a BMI of 25 - 29.9 means you are overweight. Obesity is a BMI of 30 and above. Obesity is then classified into three categories:

Class 1: BMI of 30 - 34.9
Class II: BMI 35 - 39.9
Class III: BMI of 40 and greater

These guidelines are very important for people at risk for diabetes, heart disease, or certain cancers. It is also used to determine treatment approaches such as when surgery may be appropriate. The higher the BMI, the greater the risk for significant health problems.

Calculating Body Mass Index (BMI). One's body mass index (BMI) is calculated by multiplying a person's weight in pounds by 703, dividing by the height in inches, and then dividing that number by the height in inches. The steps are as follows:

Multiply one's weight in pounds by 703
Divide that answer by height in inches
Divide that answer again by height in inches

For example, a woman who weighs 150 pounds and is five feet eight inches (or 68 inches) tall has a BMI of 22.8.

Waist Circumference and Waist-Hip Ratio. The extent of abdominal fat can also be used in assessing risk of disease. Some studies suggest that:

Women whose waistlines are over 31.5 inches and men whose waists measure over 37 inches should watch their weight.
A waist size greater than 35 inches in women and 40 inches in men is associated with a higher risk for heart disease, diabetes, and impaired functioning.

Evidence strongly suggests that more body fat around the abdomen and hips (the apple-shape) is a more consistent predictor of heart problems and health risks than BMI.

The distribution of fat can be evaluated by dividing waist size by hip size. For example, a woman with a 30-inch waist and 40-inch hip circumference would have a ratio of 0.75; one with a 41-inch waist and 39-inch hips would have a ratio of 1.05. The lower the ratio the better. The risk of heart disease rises sharply for women with ratios above 0.8 and for men with ratios above 1.0.

Click the icon to see a depiction of the waist-to-hip ratio.

Anthropometry. Anthropometry is the measurement of skin fold thickness in different areas, particularly around the triceps, shoulder blades, and hips. This measurement is useful in determining how much weight is due to muscle or fat.

Biological and Medical Causes

Obesity results when a person consumes more calories than they need for the energy they use. Several different factors may influence weight gain.

About 90% of people who lose weight through dieting gain every pound back regardless of their weight-loss method.

Some evidence suggests that every person has an inherited weight. This range varies by only about 10% either up or down from some set point. For instance, a man whose "genetically-determined" weight is 200 pounds would tend to swing from 180 - 220 pounds. He would be unlikely to lose or gain more than this.

Genetic factors may play some part in 70 - 80% of obesity cases.

Appetite is determined by processes that occur both in the brain and gastrointestinal tract. Eating patterns are controlled by areas in the hypothalamus and pituitary glands (in the brain). The body produces a number of molecules that increases or decreases appetite. In some cases, the following factors may produce imbalances in this process:

Insulin. Insulin is a hormone that helps change blood sugar (glucose) into energy. During digestion, carbohydrates from our diet break down into different types of sugar molecules (including glucose). Proteins from our diet break down into smaller molecules called amino acids. Immediately after eating, blood glucose levels rise. This triggers the release of insulin, which pours into the bloodstream. Insulin pushes the glucose and amino acids into cells and muscles. Insulin and other hormones determine which nutrients will be burned for energy or stored for future use. The inability to use insulin efficiently (insulin resistance) has been associated with both obesity and diabetes.
Leptin. Leptin is a hormone that is released by fat cells. A number of scientists think this hormone may also be released by cells in the stomach. Leptin appears to play an important role in insulin resistance and fat storage in the body, but its role in obesity is unclear. The most likely scenario is that leptin levels rise as the cells store more fat. This increase in leptin levels decreases appetite. Falling levels of leptin make you feel hungry. In people who have genetically lower levels of leptin, however, the brain may be tricked into thinking that it is always starving because there is no leptin to decrease appetite. This can lead to weight gain.
Resistin. Resistin is a hormone produced by fat cells. It makes the body resistant to insulin activity. Some experts believe it may help explain the role of obesity in diabetes type 2.
Intestinal Chemicals. Ghrelin is a chemical produced in the stomach. It appears to be important in triggering the desire to eat. Peptide YY3–36 (PYY) is a substance secreted in the intestines after a meal. The level of PYY is proportionate to the number of calories a person eats. PYY tells the brain that you feel full. Deficiencies in ghrelin and PYY may contribute to some cases of obesity. Researchers are hoping that blocking ghrelin or infusing PYY may be possible treatments for obesity.
Other Chemicals. Many brain chemicals are being studied for their role in appetite stimulation and weight gain. Among them are neuropeptide Y, melanocortins, agouti-related protein, and melanocyte stimulating hormone. Pain-relieving chemicals called endorphins may be critical in reducing appetite and regulating energy use. Cholecystokinin, a hormone released in the upper intestine that stimulates digestive juices, may work to control meal size.

Insulin is a hormone produced by the pancreas that is necessary for cells to be able to use blood sugar.

Genetics may directly contribute to severe obesity in people with family histories of the problem. Genetic factors such as slow metabolisms may also make people more likely to be overweight. At least seven genetic mutations have been associated with specific and uncommon cases of severe obesity. Some are outlined below.

HOB1 (human obesity 1) is a gene that is linked to a high BMI in women.
Leptin gene variants have been linked to leptin deficiencies and obesity.
Melanocortin-4 receptor is a gene that helps turn off the urge to eat. It may not work properly in those with a family history of obesity.
Researchers have also identified a mutation in a gene for a protein called proopiomelanocortin, which results in a syndrome of obesity, red hair, and deficiencies in stress hormones.
A protein called agouti-related protein increases hunger. About 5% of severely obese people have mutations that over-respond to agouti-related protein.

Genetics also determine the number of fat cells a person has. Some people are simply born with more. It should be noted that even when genetic factors are present, a person can still control their diet.

The Thrifty Gene. Some experts think the existence of a so-called "thrifty" gene regulates changes in hormone levels, to accommodate seasonal changes. Theoretically, it works in the following manner:

In certain populations, hormones are released during seasons when food supplies have traditionally been low. This leads to insulin resistance and increased fat storage.
The process is reversed in seasons when food is readily available.
Because modern industrialization has made high carbohydrate and fatty foods available all year long, the gene no longer serves a useful function. Fat, originally stored for famine situations, is not used.

This theory could explain why the previously nomadic Native American tribes who now have Western dietary habits have such high rates of Type 2 diabetes and obesity. In the past, the traditional low-fat, high-fiber foods tribe members ate may have protected them from obesity and type 2 diabetes. Today, these tribes' diet consists of more Western foods, which are higher in fat. Furthermore, these foods are readily available year-round, and many members of the tribe are sedentary. The result is a very high incidence of Type 2 diabetes and obesity. Although genetic abnormalities may make it harder or easier to lose weight, the occurrence of obesity has dramatically increased over the past two decades, and genes cannot have changed within that short amount of time. Our ability to use the food that we eat evolved so that our body could conserve energy and store fat during times of famine. Most cases of obesity now occur in people with normal body function who live in industrialized nations, where there is more than enough food.

A number of medical conditions may contribute to being overweight, but rarely are they a primary cause of obesity.

Hypothyroidism is sometimes associated with weight gain. But, patients with an underactive thyroid generally show only a moderate weight increase of five to 10 pounds.
Very rare genetic disorders, including Froehlich's syndrome in boys, Laurence-Moon-Biedl, and the Prader-Willi syndromes, cause obesity.
Abnormalities or injury to the hypothalamus gland can cause hypothalamic obesity.
Cushing's disease is a rare condition caused by high levels of steroid hormones. It results in obesity, a moon-shaped face, and muscle wasting.
Obesity is also linked to polycystic ovarian syndrome, a hormonal disorder in women.

Click the icon to see an image of polycystic ovaries.

Some prescription medications contribute to weight gain, usually by increasing appetite. Such drugs include the following:

Corticosteroids
Female hormone treatments, including some oral birth control pills (effect is usually temporary), and certain progestins (such as Megestrol) used to treat cancer
Antidepressants and anti-psychotic drugs, including lithium and valproate
Insulin and insulin-stimulating drugs used to treat diabetes often lead to weight gain, a particularly unfortunate conflict of interest for obese individuals with type 2 diabetes

You should not stop taking any medications without your doctor's knowledge.

Cultural and Emotional Causes

Enough food is produced in the US to supply 3,800 calories every day to each man, woman, and child in the country, far more than the average person needs to sustain life. In a 2002 study, participants carefully recorded everything they ate and drank, and all activities and psychological factors surrounding the eating events. The people who gained weight ate more and their portions were larger than those who did not. This may be an obvious conclusion, but the public press often plays up biologic factors involved with obesity and overlooks the simple notion that Americans eat too much and exercise too little.

Obesity is dramatically increasing not only in American children and adults, but also in every country that has adopted similar cultural habits. The World Health Organization now considers obesity to be a global epidemic and a public health problem as more nations become "Westernized." In spite of the proven health risks of obesity, the government, insurance companies, and the medical profession do not spend nearly enough money to balance the commercial and cultural pressures that are producing millions of overweight people.

In 2007, the Robert Wood Johnson Foundation sounded a positive note with the announcement of a $500 million initiative, aimed at “reversing the childhood obesity epidemic by 2015.” The money will be used for research, education, and activities that promote healthy eating among America’s children.

Perhaps the primary reason for the dramatic rise in obesity is the sedentary (inactive) lives led by most Americans, including children and young people. In a 2003 study comparing modern life to the past, researchers found that labor saving devices had reduced a person's energy use by 111 calories a day -- adding up to an extra 11 pounds a year. Half the difference in energy use was due to less walking. At the same time, according to the U.S. Centers for Disease Control and Prevention, between 1970 and 2000 the typical American man increased his caloric intake by 168 calories a day (good for 17 pounds a year) while the average woman added 335 calories a day.

Regular television watching has been singled as the most hazardous pastime. According to a major 2003 study, for every 2 hours a person spends in front of the TV each day, the risk for obesity increases by 23% and for type 2 diabetes by 14%. In the study, TV watching produced the lowest metabolic rates compared to sewing, playing board games, reading, writing, and driving a car. Just the act of watching TV encourages unhealthy snacks and eating patterns. In addition, the advertising on the television complicates the problem by promoting fast foods, cereal, and snack products that are high in salt, fats, and carbohydrates. Even worse, much of these advertisements are directed at children -- the most vulnerable group.

People are not only eating more food than they did 20 years ago, they are also replacing home cooking with packaged foods, fast food, and dining out. This behavior, according to studies, places people at higher risk for obesity. Fast foods may be more harmful than restaurant cooking. These foods tend to be served in larger portions. They generally contain more calories and unhealthy fats, and less nutritious ingredients, than homemade or restaurant meals. Snack foods and sweet beverages, including juice and soft drinks, are specific problems that add to the increasing rates of obesity. Frequent small, healthy meals (instead of two or three large daily meals) have been associated with lower weights.

People react differently to stress. Some overeat and gain weight and others stop eating and lose weight. People who gain weight in response to stress often overeat foods high in sugar, fats, and salt. A 2003 study on rats suggested that stress hormones increase the pleasure of eating such so-called "comfort foods." Furthermore, the study supported previous research showing that stress-related eating was connected to the unhealthy accumulation of abdominal fat.

Risk Factors

Where you live plays a role in your risk for obesity. Simply living in the United States makes a person more susceptible to obesity. The prevalence of obesity in America has risen dramatically over the past few years and continues to increase.

According to the latest figures available, 32.2% of American adults (aged 20 and older) are obese (BMI over 30) -- up from about 23% in the early 1990s.
The number of Americans aged 20 - 74 who were overweight also increased -- from about 44.8% in 1960 to 65.2% in 2002.
The rate of extreme obesity (BMI > 40) increased from 0.8% in 1960 to 4.9% in 2002.
Obesity has increased in every state, in both men and women, across all age groups, and in every ethnic group, although some groups may face slightly higher risks than others.

Fat tends to settle in certain regions, depending on gender. Women gain fat predominantly in the stomach, hips and thighs, while men tend to gain fat in the belly and waist.

Risk by Age. People of any age are at risk for obesity. More children and adolescents are overweight in America than ever before. Gaining some weight is inevitable with age and adding about 10 pounds to a normal base weight over time is not harmful. The current weight gain in American adults over 50, however, is significant. By age 55, the average American has added nearly 40 pounds of fat during the course of adulthood. This condition is made worse by the fact that muscle and bone mass decrease with age.

Risk by Gender. In men, BMI tends to increase until age 50 and then it levels off. In women, weight tends to increase until age 70 before it plateaus. A 2000 study found that there are three high-risk periods for weight gain in women.

The first is at the onset of menstruation, particularly if it is early. In fact, a study released in March 2007 found that obesity in young girls results in early puberty -- as early as age 9. This, in turn, increases the risk for more weight gain as girls enter puberty.
The second is after pregnancy, with higher risk for women who are already overweight.
Finally, many women gain weight after menopause.

These findings are significant because they may allow women to target high-risk times, and consequently prevent unnecessary weight gain.

Risk by Economic Group. Obesity is more prevalent in lower economic groups. One 2002 study reported that women who reported that they did not have enough food were more likely to be overweight than those who said they had sufficient food. Researchers discovered that the low-income women tended to have fewer fruits and vegetables but were actually taking in more calories a day than higher-income women. However, obesity is increasing in young adults with college education as well as in other groups.

Ethnic Groups. Among ethnic groups in general, African-American women are more overweight than Caucasian women but African-American men are less obese than Caucasian men. (Currently, 80% of African-American women are overweight.) Hispanic men and women tend to weigh more than Caucasians.

US Regions. Regionally, the prevalence of obesity is lowest in the Western states and highest in the South.

A number of dietary habits put people at risk for becoming overweight:

Night-Eating Syndrome. Night-eating syndrome is defined as having no appetite in the morning, insomnia, and consuming more than half of daily food intake after 6:00 PM. It is associated with obesity and is difficult to treat. Stress reduction and relaxation techniques may be helpful.
Binge Eating and Eating Disorders. About 30% of people who are obese are binge eaters who typically consume 5,000 - 15,000 calories in one sitting. To be diagnosed as a binge eater, a person has to binge at least twice a week for 6 months. Many experts believe that binge-eating carbohydrates causes an increase in a natural opiate leading to dependence on carbohydrates. Therefore, this condition should be treated as an addiction. Other eating disorders are bulimia and anorexia. Bulimia is binge eating followed by purging in order to lose weight. Anorexia nervosa is a mental illness in which the person refuses to maintain weight at the normal level. The patient with anorexia has a terrible fear of getting fat, and an abnormal perception of what his or her body looks like. Both conditions pose risks for serious medical problems, and anorexia nervosa can be life-threatening. A combined approach using behavioral therapy and antidepressants may help these individuals. [See In-Depth Report #49: Eating disorders.]
Restrained Eating. Some people, mostly middle-aged women who have normal weight, have a pattern referred to as restrained eating. This pattern requires a high level of conscious control and usually maintains a lower weight. However, such restraint places these individuals at higher risk for loss of control and subsequent overeating.
Infrequent Eating. There is some evidence to suggest that eating small frequent meals uses more calories than infrequent large meals. It should be strongly noted, however, that packaged snack foods add calories and some do not produce a feeling of being full, so that people simply eat more than they should.

Anyone with Sedentary Lifestyles. Office workers, drivers, and anyone whose lifestyle involves sitting for long periods are at higher risk for obesity.

Ex-Smokers. The trend toward weight increase has followed the trend for quitting smoking. Nicotine increases the metabolic rate, and quitting, even without eating more, can cause weight gain, which may be considerable. It is important to note that weight control is not a valid reason to smoke. People in previous centuries did not smoke cigarettes, nor were they usually obese.

Shift-Workers. A recent study found that individuals who work late shifts (between 4 p.m. and 8 a.m.) tend to eat more and take longer naps than day workers and are more likely to gain excess weight.

People with Disabilities. Obesity rates are higher than average in people with physical or mental disabilities. Those with disabilities in the lower part of the body, such as the legs, are at highest risk.

Overweight in children and adolescents is rising at an alarming rate. In 2004, 19% of young children aged 6 - 11 were overweight, an increase of 8% from 1994. Among children aged 25, 13.9% were overweight in 2004, up from 7.2% 10 years earlier.

Definition of Overweight in Children

Children and adolescents are considered to be overweight if their BMI is above 95% of the children in their age and sex categories. Ethnic variations, timing of growth spurts, and higher normal fat levels around puberty can affect these measurements.

Causes and Risk Factors for Overweight in Children

Lifestyle Factors. Without educational or parental guidance, children are extremely vulnerable to the intense cultural pressures that are largely responsible for the obesity epidemic. The following are some specific problems created by the culture:

Excessive television watching plays a critical role in obesity in children. Not only is it a sedentary activity, but television also offers innumerable temptations with its advertisements for fast foods, sugar cereals, and unhealthy snacks. In one study obesity rates were lowest in children who watched television 1 hour or less a day and highest in those who watched 4 or more hours.
Sugar, particularly from soda, other sweetened beverages, and fruit juice, may be the major contributor to childhood obesity. One study reported that drinking soda regularly increases a child's risk for obesity by 60%. The average American adolescent consumes 15 - 20 extra teaspoons of sugar a day just from soda and sugary drinks. (Juice, while better than soda, is still filled with sugar.)
Less physical exercise and greater sedentary activities play another significant role in obesity in children. A high level of physical activity -- not just using up energy -- is important for weight control in young people. Unfortunately, according to one study, the annual distance walked by children has fallen by nearly 30% since 1972, partially because more parents are driving their children to school out of fear of abduction, molestation, and traffic accidents. Schools are also offering fewer opportunities for daily physical activities than in the past.

Neither the media nor the educational system has strong well-financed programs that encourage healthy alternatives, including exercise and healthy foods.

Family History. Parental obesity more than doubles the risk that a young child, whether thin or overweight, will become obese as an adult. In older children and teenagers, obesity in parents starts to count less as a predictor for body weight than their own weight. The risk for obesity may be due to environmental or genetic factors, or both.

Ethnic and Socioeconomic Factors. As in adult populations, children from lower socioeconomic groups and minority populations are at higher risk for obesity. For example, among young Mexican Americans and African-Americans, there has been an increase in overweight prevalence of about 13% to over 23%.

Factors Surrounding Birth. The following factors surrounding birth are associated with a child's weight:

Low birth weight is a risk factor for later obesity and diabetes. One theory is that humans have a "thrifty gene" that produces metabolic changes in infants with low birth weight. Such changes affect insulin and fat accumulation, in order to produce a "catch-up" weight in these young children as quickly as possible. This rapid weight gain in infancy increases the risk for obesity in children and young adults.
In a study of African-American children, having an overweight pregnant mother increased the risk for later weight gain, but low birth weight did not.

Although some small studies have reported protection against obesity from breastfeeding, evidence is weak. In a 2003 study, for example, children who were breast fed for 3 - 5 months had a lower risk for obesity, but prolonged breastfeeding had no effect. Nevertheless, given the healthful effects of breast feeding and the possibility that it may have even a slight impact on childhood obesity, it is highly recommended.

Biological Effect of Childhood Overweight on Adult Weight

Achieving a healthy weight becomes more difficult as children get older. The odds of obesity persisting into adulthood ranges from 20% in 4 year olds to 80% in teenagers. One reason for the persistence is biological. The fat cells change in number or mass depending on a person's age:

Fat cells themselves multiply during two growth periods: early childhood and adolescence. Overeating during those times increases the number of fat cells. Some people are also just born with more fat cells.
After adolescence, fat cells tend to increase in mass rather than quantity, so that adults who overeat and gain weight tend to have larger fat cells, not more of them. This growth in mass may be responsible for the greater risk of persistent obesity among teenagers compared to small children who are overweight. Losing weight after adolescence reduces the size of the fat cells but not their number, so weight loss becomes much more difficult.

Health Consequences of Childhood Overweight

Children and adolescents who are overweight have poorer health than other children. Studies are reporting unhealthy cholesterol levels and high blood pressure in overweight children and adolescents. Of great concern is the dramatic increase in type 2 diabetes in young people, which is largely due to the increase in overweight children. Overweight in children is also linked to asthma, gallbladder problems, sleep apnea, and liver abnormalities. Overweight girls are more likely to enter puberty early, according to a new study, and subsequently be at higher risk for breast cancer.

It is not clear yet how many of these childhood problems persist in people who achieve normal weight as adults. Staying overweight into adulthood certainly carries health risks.

Managing Overweight Children

Childhood obesity is best treated by a non-drug, multidisciplinary approach including diet, behavior modification, and exercise. Evidence suggests that reducing calories by only 200 - 260 per day would prevent weight gain in most overweight children. Here some tips for children who are overweight:

Limit (or avoid, if possible) take out, fast foods, high-sugar snacks, commercial packaged snacks, soda, and sugar-sweetened beverages (including too much juice).
Let children snack but make sure the snacks are healthy. Eating small frequent healthy meals (instead of two or three large ones) has been associated with being thinner and having a better cholesterol profile.
Let children choose their own food portions. One study indicated that children naturally ate 25% less when they chose their own portion size. When they were given larger portions their bite sizes were larger and they ate more.
Do not criticize a child for being overweight. It does not help and such attitudes could put children at risk for eating disorders, which are equal or even greater dangers to their health.
Limit television, video games, and computer use to a few hours a week. This can contribute significantly to weight control, regardless of diet and physical activity.
For young children, try the traffic-light diet. Food is designated with stoplight colors depending on their high caloric content: Green for go (low calories); yellow for "eat with caution" (medium calories); red for "stop" (high calories).
Try a low glycemic index diet. This may be as beneficial, and possibly more, than a standard reduced-fat diet in overweight children. Such a diet focuses on certain carbohydrates (for example, dried beans and soy), which raise blood sugar more slowly than other types of carbohydrates. This diet is sometimes used in diabetes, and as a dietary approach in overweight adults. [See In-Depth Report #42: Diabetes diet.]

Click the icon to see an image about TV watching.

Click the icon to see an image of childhood overweight.

Complications

General Adverse Effects of Obesity. Obesity, defined as a BMI of 30 or over, accounts for nearly 300,000 deaths in the U.S. each year. It is associated with more chronic health problems than smoking, heavy drinking, or poverty. Furthermore, given the current increase in obesity, it will surpass smoking as the most important preventable cause of death in America.

Some studies indicate the following health risks by body mass:

The lowest risks for heart disease, diabetes, and some cancers are in people with BMI values of 21 - 25.
The risks increase slightly when BMI values are between 25 - 27.
The risks are significant in BMIs between 27 - 30.
The same risks are dramatic at BMIs over 30.

Anyone with chronic health problems such as heart or lung disease, stroke, or arthritis, should be concerned about extra weight. This same concern also applies to people with known risk factors for such conditions.

Metabolic Changes. As fat stores increase, the fat cells themselves enlarge and produce chemicals that increase the risk for several diseases. Such diseases may include diabetes, high blood pressure, gallbladder disease, and some cancers.
Increased Mass. The increased body weight itself causes problems that result in injury and diseases, including osteoarthritis and sleep apnea.
Harmful Fat Cell Types. Weight concentrated around the abdomen and in the upper part of the body (the apple shape) poses a higher health risk than fat that settles around the hips and flank (the pear shape). Fat cells in the upper part of the body appear to have different qualities from those found in the lower parts. In fact, studies suggest a higher risk for diabetes in people with the "apple shape" and lower risk in those who are "pear shaped."

Weight gain in the area of and above the waist (apple type) is more dangerous than weight gained around the hips and flank area (pear type). Fat cells in the upper body have different qualities than those found in hips and thighs.

General Adverse Effects of Being Overweight (Not Obese). It is still not clear if being overweight (a BMI of 25 - 29.9) hurts healthy people with no risk factors for serious illnesses.

According to one 2001 study, just being overweight increased the risk for developing diabetes, gallstones, hypertension, heart disease, stroke, and colon cancer. The risk rose according to how much the individuals were overweight. In any case, adults who are overweight in middle age face a poor quality of life as they age, with the quality declining the greater the weight. One study suggested, however, that being over 65 and overweight (but not obese) is not associated with higher mortality rates.

Some experts argue, in fact, that in anyone who is not severely obese, it is the unhealthy diet and sedentary lifestyle that causes harm -- not weight per se. In support of this argument, a British study found that overweight fit individuals had half the death rate of unfit trim individuals.

Being somewhat overweight may also have some benefits under specific circumstances:

In older women, some excess fat may produce extra estrogen that helps slow down bone loss, and insulates bones from fall-related injuries. It should be strongly noted, however, that when older overweight women lose weight they report less pain, improved vitality, and improved physical function. The same positive effect of overweight does not appear to hold in older men.
Conditioned athletes may have high BMIs because of very dense muscle tissue. Being fit in general may protect many overweight people.
Some evidence suggests that Caucasians have the lowest mortality with BMIs of 24.3 - 24.7 while African-Americans are better off in the range of 26.8 - 27.1.
Children may have higher normal fat levels during growth spurts and around puberty.

Individuals with a BMI of at least 30 have a 10 - 50% increased rate of death from all causes, compared with individuals with a BMI of 20 - 25. Mortality rates from many causes are higher in obese people, but heart disease is the primary cause of death. People who are obese have almost three times the risk for heart disease as people with normal weights. Being physically unfit adds to the risk.

Weight concentrated around the abdomen and in the upper part of the body (apple shape) is particularly associated with insulin resistance and diabetes, heart disease, high blood pressure, stroke, and unhealthy cholesterol levels. Fat that settles in a pear shape around the hips and lower body appears to have a lower association with these conditions.

Obesity poses many dangers to the heart and circulatory system.

Damage in the Blood Vessels. As people age, changes in body fat (particularly increasing abdominal fat) seem to cause stiffness in the aorta, the major blood vessel leading from the heart. Studies are finding higher levels of a factor called C-reactive protein (CRP) in people with obesity and abdominal fat. CRP is now considered to be a marker for inflammation and damage in the arteries. (Losing weight reduces CRP levels.)

High Blood Pressure. High blood pressure is the health problem most commonly associated with obesity, and the greater the weight, the greater the risk. High blood pressure carries serious risks of stroke, heart attack, and heart failure. The link between obesity and high blood pressure is complex, and may be a combination of genetic, population, and biological factors. Many studies have reported that modest weight loss is beneficial for reducing existing high blood pressure. [See In-Depth Report #14: High blood pressure.]

Heart Failure. An important 2002 study reported that obesity might account for 11% of heart failure cases in men and 14% in women. This link existed independently of other risk factors, such as high blood pressure, sleep apnea, and diabetes, which are also associated with obesity. The biologic mechanisms involved in obesity that lead specifically to heart failure are not clear. [See In-Depth Report #13: Heart failure.]

Unhealthy Cholesterol Levels and Lipid Levels. The effect of obesity on cholesterol levels is complex. Although obesity does not appear to be strongly associated with overall cholesterol levels, among obese individuals triglyceride levels (the major form of fat storage in the body) are usually high, while HDL levels (the "good" cholesterol) tend to be low. Both conditions are risk factors for heart disease. [See In-Depth Report #23: Cholesterol.]

Click the icon to see an image of coronary artery disease.

Stroke. Obesity is also associated with a higher risk for stroke. [See In-Depth Report #45: Stroke.]

Type 2 Diabetes and Insulin Resistance. Most people with type 2 diabetes are obese and, in fact, studies strongly suggest that weight loss may be the key in controlling the current epidemic of type 2 diabetes. The common factor appears to be insulin resistance. Insulin is a critical hormone in the use of sugar. In type 2 diabetes, different factors cause the body to become insulin resistant -- that is, the body can no longer respond properly to insulin. This has the effect of increasing sugar levels in the blood, the hallmark of diabetes. Both obesity and insulin resistance, at different phases, are marked by high levels of certain chemicals. It is not known yet if the higher levels are simply a product of obesity, or play some role in causing diabetes.

Insulin resistance is also associated with high blood pressure and abnormalities in blood clotting. Some research indicates that obesity, in fact, is the one common element linking insulin resistance, diabetes type 2, and high blood pressure. [See In-Depth Report #60: Diabetes - type 2.]

Metabolic Syndrome. Metabolic syndrome (also called syndrome X) is a pre-diabetic condition that is significantly associated with heart disease and higher mortality rates from all causes. The syndrome consists of obesity marked by abdominal fat, unhealthy cholesterol levels, high blood pressure, and insulin resistance. A 2002 study estimated that nearly a quarter of the U.S. population now has this condition. Even worse, according to a 2003 study, nearly a million American teenagers have this syndrome. A combination of weight loss and exercise is an effective treatment for this syndrome.

The American Cancer Society released new cancer prevention guidelines in September 2006. The guidelines stress the importance of keeping a healthy weight throughout life. The Society indicates that healthy weight is even more important than eating specific healthy foods, when it comes to cancer prevention.

Obesity has been associated with a higher risk for cancer in general and specific cancers in particular. Studies have also suggested that restricting calories reduces the risk for cancer. Some experts believe that effective weight control for children and adults could reduce cancer rates by 30 - 40%. One way obesity may increase the risk for cancer is its association with high levels of hormones called growth factors, which can trigger rapid cell production leading to cancer.

Uterine Cancers. The risk of uterine cancer in obese women appears to be two or three times higher than in thinner women.

Prostate Cancer. New studies from 2005 and 2006 report that obesity is associated with an increase in prostate cancer mortality, although not with the risk for less aggressive forms of prostate cancer.

Click the icon to see an image of prostate cancer.

Breast Cancer. Studies are mixed on the association between obesity and breast cancer. A number of studies have linked obesity to breast cancer in postmenopausal women, particularly in women who begin to gain weight after age 18.

Click the icon to see an illustrated series detailing a breast cancer surgery (mastectomy).

Gallbladder Cancer. Obese women are at higher risk for gallbladder cancer.

Gastrointestinal Cancers. A number of cancers in the gastrointestinal tract have been associated with obesity:

Cancer of the esophagus may be due to a higher incidence of gastroesophageal reflux disorder (heartburn) in people who are overweight.
Colon cancer has been linked to increased body mass in both men and women.
Pancreatic cancer and obesity have been weakly linked, with one study reporting a lower risk in overweight people who are physically active.

Click the icon to see an illustrated series detailing a colon cancer surgery.

Muscles and Bones

Obesity places stress on bones and muscles. Studies report that the incidence of osteoarthritis is significantly increased in people who are overweight. People who are obese are also at higher risk for carpal tunnel syndrome and other problems involving nerves in their wrists and hands. It should be noted that some weight may be protective against osteoporosis (loss of bone thickness).

Obesity increases the risk for the following mouth and eye disorders:

Gum disease
Cataracts
Maculopathy, an eye disease related to aging

Infertility. Abnormal amounts of body fat, either 10 - 15% too high or too low, can contribute to infertility in women. Obesity is specially related to certain infertility problems, such as uterine fibroids or menstrual irregularities. In men, obesity can contribute to reduced testosterone levels.

Effect on Pregnancy. Obesity has many dangerous effects on pregnancy. These include high blood pressure, gestational diabetes (diabetes, usually temporary, that occurs during pregnancy), urinary tract infections, blood clots, prolonged labor, and higher fetal death rate in late stages of pregnancy. Obesity is also associated with increased rates of cesarean delivery. Infants of women who are obese are also at higher risk for neural tube birth defects, which affect the brain or spine. Folic acid supplements, ordinarily effective in preventing these conditions, may not be as protective in overweight women.

Obesity is thought to be a risk factor for symptoms of adult-onset asthma. Though there is evidence that obesity causes wheezing and shortness of breath, it does not appear to be strongly associated with the disease mechanisms in the lungs that cause true asthma.

Obesity also puts people at risk for hypoxia, a condition in which there is not enough oxygen to meet the body's needs. Obese people need to work harder to breathe. They tend to have breathing muscles and lungs that do not work as well as those in thinner people.

The Pickwickian syndrome, named for an overweight character in a Dickens novel, occurs in severe obesity when lack of oxygen produces intense and chronic sleepiness and, eventually, heart failure.

Nonalcoholic Fatty Liver Disease. People with obesity, particularly if they also have type 2 diabetes, are at higher risk for a condition called nonalcoholic fatty liver disease, also called nonalcoholic steatohepatitis (NASH). This condition causes liver damage that is similar to liver injury seen in alcoholism. In some cases, it can be very serious and require liver transplantation. It occurs in about half of people with diabetes, and 20 - 50% of obese people, depending on how severe their obesity is. NASH can also occur in overweight children.

Gallstones. The incidence of gallstones is significantly higher in obese women and men. The risk for stone formation is also high if a person loses weight too quickly. In people on ultra-low calorie diets, gallstones may be prevented by taking ursodeoxycholic acid (Actigall).

Click the icon to see an image of gallstones.

People who are obese and nap tend to fall asleep faster and sleep longer during the day. At night, however, it takes them longer to fall asleep, and they sleep less than people with normal weights. In an apparent vicious circle, studies have suggested that obesity not only interferes with sleep but that sleep problems may actually contribute to obesity.

Sleep Apnea. Obesity, particularly the apple shape, is strongly associated with sleep apnea, which occurs when the upper throat relaxes and collapses from time to time during sleep. This collapse temporarily blocks the passage of air. Sleep apnea is increasingly being viewed as a potentially serious health problem, which may lead to complications such as heart disease and stroke. Some studies suggest that among overweight people, those who have sleep apnea have a greater risk of heart disease than those without it. In one study, the more obese a person with sleep apnea was, the higher the pressure on the airway, and therefore the greater the obstruction of the airway. Obstructive sleep apnea may also add to obesity, however, as sleepy people tend to be sedentary. Some studies indicate that treating sleep apnea may help people lose abdominal fat.

Narcolepsy. A small European study found a link between narcolepsy (a sleep disorder characterized by excessive daytime sleepiness with frequent daily sleep attacks) and high BMI.

Depression. A number of studies have reported an association between depression and obesity, particularly in obese women. There may be a number of factors to explain the link. In some cases of atypical depression, people overeat and may gain weight. Overweight people may also become depressed because of social problems and a poor self-image. In these cases, depression usually disappears when people lose weight.

There is evidence, however, that obesity itself may impair levels of tryptophan -- a chemical needed to make serotonin, a brain chemical associated with mental well-being. In one study, even after people lost weight, tryptophan levels were lower than normal.

There does not appear to be any association between depression and obesity in men.

Social Problems. One long-term study reported that overweight young women completed fewer years of school, were 20% less likely to be married, and had 10% higher rates of household poverty than their thinner peer. Obese young men were also less likely to be married, and their incomes were lower than their thinner peers. Nevertheless, studies consistently show that overweight males (both boys and men) are not as severely emotionally affected as females of any age. Women and girls tend to blame themselves for being heavy, while males tend to blame being overweight on outside factors.

Weight Loss and Maintenance

Even modest weight loss can reduce the risk factors for heart disease and diabetes. The simplest (but still difficult) approach to weight loss is reducing calories and exercising at least 150 minutes a week. Behavioral and mental changes in eating habits, physical activity, and attitudes about food and weight are also essential to weight management. For people who are very overweight and cannot lose weight through lifestyle changes, a number of effective weight-loss medications are available. For those with severe obesity, surgical procedures are proving to be very beneficial.

Some Tips for Losing Weight. The following are some general suggestions for dieters:

Start with realistic goals. Diet failure is extremely common, and the odds of significant weight loss are low, particularly in people with the highest weights. People who are able to restrict calories, engage in an exercise program, and get help in making behavioral changes can expect to lose between 5 - 10% of their current body weight. That is generally all that is needed to achieve meaningful health changes. Certainly, the distorted image of a super-thin female shape should not be anyone's goal.
Maintain a regular exercise program, assuming you have no health problems that will stop you. Choose a program that you enjoy. Check with your doctor about any health considerations. [See In-Depth Report #29: Exercise.]
Do not use hunger pangs as cues to eat. A stomach that has been stretched by large meals will continue to signal hunger for large amounts of food until its size reduces over time with smaller meals.
Be honest about how much you eat and start by recording all calories in writing. Studies suggest that when many people report their own calories intake they significantly underestimate their consumption of high-calorie and over-estimate the low-calorie foods. People who do not carefully note everything they eat tend to take in too many calories when they believe they are dieting.
Observe weekend eating. People tend to eat more on the weekends. If it is difficult to monitor all meals during the week, it be may be useful to at least track eating habits during the weekends.
Once the pounds are lost, do your best to keep the healthier weight. Make daily, even hourly, conscious decisions about eating and exercising activities. Such thinking, in many cases, can become automatic and not painful.
Don't give up, even after repeated weight loss failures. Most studies indicate that yo-yo dieting or weight cycling have no bad psychological or physical effects. Repeated dieting also does not harm the body's ability to burn calories efficiently.
Weight loss, in any case, should not be the only or even the primary goal for people concerned about their health. The success of weight loss efforts should be evaluated according to improvements in disease risk factors or symptoms, and by the adoption of healthy lifestyle habits, not just by the number of pounds lost.


Lifestyle	Reduce rate of eating. Keep food records. Eliminate environmental triggers to eating. Identify high-risk situations for overeating. Separate eating from other activities.
Exercise	Face up to emotional barriers to exercise. Understand the link between exercise and weight control. Establish reasonable exercise goals. Develop a plan for regular activity. Add increased activity into daily lifestyle.
Attitudes	Develop reasonable weight-loss goals. Avoid "all or none" thinking. Focus attention away from the scale and toward behavior. Uncouple weight from self-esteem. If you "fall off the wagon," take steps to ensure the situation does not repeat (recover from lapses with constructive action).
Relationships	Understand the key role of social support to health. Identify supportive others. Match personal style to support-seeking activities. Be specific in making support requests. Be assertive but reinforcing in drawing help from others.
Nutrition	Resist the temptation of popular fad diets. Eat with your health in mind; do not concentrate on what should be "off-limits." Eat with moderation in mind. Maximize fiber. Develop a tailored plan.
From Brownell KD. The LEARN Program for Weight Control. 7th ed. Dallas, Tex: American Health Publishing Company; 1998.

Weight Management

There are many approaches to dieting and many claims for great success with various fad diets. To date, although many diets achieve effective immediate weight loss, none has emerged as an effective tool for maintaining healthy weight. The only definite recommendation that can be made about any diet plan is to be sure it includes an exercise program, assuming there are no health problems to forbid it.

The original food pyramid, with four food groups, has been replaced with an updated food guide called "My Pyramid." This illustrates the relative proportions of different foods that make up a nutritious, well-balanced diet and includes exercise.

Calorie restriction has been the cornerstone of obesity treatment. The standard dietary recommendations for losing weight are the following:

As a rough rule of thumb, one pound of fat equals about 3,500 calories. A person could lose a pound a week by reducing daily caloric intake by about 500 calories a day. Naturally, the more severe the daily calorie restriction, the faster the weight loss. Very-low calorie diets have also been associated with better success, but extreme diets can have some serious health consequences.
To determine your daily calories requirements, multiply the number of pounds of ideal weight by 12 - 15 calories. The number of calories per pound depends on gender, age, and activity levels. For instance, a 50-year old woman who wants to maintain a weight of 135 pounds and is mildly active might require only 12 calories per pound (1,620 calories a day). A 25-year old female athlete who wants to maintain the same weight might require 25 calories per pound 2,025 (calories a day).
Fat intake should be no more than 30% of total calories. Most fats should be in the form of monounsaturated fats (such as olive oil). Saturated fats (found in animal products) should be avoided.

Extreme diets of less than 1,100 calories carry health risks. They are also often followed by bingeing or overeating, and a return to the obese state. Such diets often do not have enough vitamins and minerals, which must then be taken as supplements. Most of the initial weight loss is in fluids. Later, fat is lost, but so is muscle, which can account for more than 30% of the weight loss. No one should be on severe diets for longer than 16 weeks, or fast for more than 2 or 3 days. Severe dieting has unpleasant side effects including fatigue, intolerance to cold, hair loss, gallstone formation, and menstrual irregularities. There have been rare reports of death from heart arrhythmias when liquid formulas did not have sufficient nutrients. Pregnant women who excessively diet during the first trimester put their unborn children at risk for birth defects. Of note, those whose diets include a high intake of fluids and much reduced protein and sodium are at risk for hyponatremia, which can cause fatigue, confusion, dizziness, and in extreme cases, coma and death.

This dietary approach requires counting only grams of fat with the goal of achieving 30% or fewer calories from fat. One gram of fat contains nine calories, while one gram of carbohydrates or protein has only four calories. Fat in your diet converts more readily to fat in the body, compared with carbohydrates or proteins. Simply switching to low-fat or skimmed dairy products may be enough for some people.

There are possible drawbacks to this approach:

Some people who reduce their fat intake may not get enough basic nutrients, including vitamins A and E, folic acid, calcium, iron, and zinc. People on low-fat diets should eat a wide variety of foods and take a multivitamin supplement, if appropriate. Calcium deficiencies may be particularly harmful in women at risk for osteoporosis.
Many people start eating foods with too many carbohydrates, believing that they are not adding calories. No one should use a low-fat diet as an excuse for eating too many carbohydrates, particularly starchy foods and sugar. A high-calorie diet from any source will add pounds.
A small study in Norway found that a diet low in fat and high in carbohydrates ("carbs") increases symptoms of psychological distress, such as depression and anger. The study compared three different diets that had varying amounts of fat and carbohydrates in each. The diets contained the same amount of calories, but differed in the percentage and type of fat. People on the low-fat, high-carbohydrate diet reported more anger and depression compared with the other two diets.
Replacing fatty foods, such as cakes, cookies, and chips, with their commercial "low-fat" counterparts does not constitute a low-fat diet. These foods generally contain more sugar and hence calories, not to mention other ingredients, which have virtually no nutritional value. In fact, a 2002 study suggested that increasing sugar may, over time, reduce levels of HDL ("good") cholesterol.
Very low-fat diets may increase the risk for stroke from hemorrhage in the brain.

Some fat in a diet is essential. It should come from plant oils and fish, however, and not from animal products or hardened oils, such as margarine. Trans-fatty acids, found in hardened oils, are actually more of a risk factor for obesity than saturated fats from animal products, although both should be avoided.

Fiber and Complex Carbohydrates. In all cases, complex carbohydrates found in whole grains and vegetables are preferred over those found in starch-heavy foods, such as pastas, white-flour products, and potatoes. Fiber is an important component of many complex carbohydrates. Fiber is almost always found only in plants, particularly vegetables, fruits, whole grains, nuts, and legumes (beans and peas). One exception is chitosan, a dietary fiber made from shellfish skeletons. Fiber cannot be digested but passes through the intestines, drawing water with it, and is eliminated as part of feces content. The following are specific advantages from high-fiber diets (up to 55 grams a day):

Insoluble fiber (found in wheat bran, whole grains, seeds, nuts, and fruit and vegetable peels) has been associated with weight loss. Studies also suggest that diets rich in fiber from whole grains reduce the risk for type 2 diabetes.
Soluble fiber (found in dried beans, oat bran, barley, apples, citrus fruits, and potatoes) has important benefits for the heart, particularly for achieving healthy cholesterol levels and possibly benefiting blood pressure as well. Simply adding breakfast cereal to a diet appears to reduce cholesterol levels. People who increase their levels of soluble fiber should also increase water and fluid intake.

High-protein, low carbohydrate diets, such as the Atkins and South Beach diets, have been touted as effective ways to produce short-term weight loss. Because of their emphasis on fats and proteins, many experts are concerned about long-term health problems. A report in the March 2006 Lancet linked the Atkins diet to life-threatening complications that caused the death of one woman. The 40-year-old woman had a deadly buildup of acids called ketones in her blood, a condition called ketoacidosis. Ketoacidosis can cause coma and death. Ketones are a known by-product of high protein, low carbohydrate diets. At low levels they can cause nausea, lightheadedness, and bad breath.

The long-term effects of these diets are still unknown. For example, the Atkins diet restricts some vegetables and most fruits, which are known to protect against serious diseases such as heart problems and cancer. The diet may also cause too much calcium to build up in the urine. This can increase the risk for kidney stones and osteoporosis. In addition, high-protein intake, particularly from meat, can be harmful in people with kidney problems. Individuals at risk for kidney stones, or those who have other kidney problems, should not go on high-protein diets without talking to their doctor first. Unfortunately, many people with diabetes are at risk of kidney problems, which could reverse any possible benefits a high-protein diet may bring them. Eating a lot of meat has also been associated with certain common cancers, notably prostate and colon cancers. A 2002 study suggested that such diets during pregnancy may increase the risk for high blood pressure in the child.

Still, significant studies say that such diets improve cholesterol and blood sugar levels. Studies in 2002 and 2003 have indicated that these diets lower blood glucose levels, which can be important in people who are diabetic. The diets also reduce triglyceride levels (unhealthy fat molecules) and increases HDL (" good") cholesterol levels. High triglyceride and low HDL levels are important risk factors for heart disease, and are common in people with type 2 diabetes. Studies are mixed on whether this type of diet reduces overall cholesterol or LDL ("bad") cholesterol levels.

Experts that promote the low carbohydrate approach argue that heart problems from obesity are due to insulin disturbances from sugar imbalances. Therefore, they believe that restricting carbohydrates is the best approach for obesity -- especially for overweight people with diabetes. More research is needed, however, to determine the long-term impact of such diets on health.

High-protein, low-carbohydrate diets include Atkins, Protein Power, Sugar Busters, and Dr. Stillman. The Atkins diet is one of the most popular and has a four-phase program:

Induction. For the first 2 weeks, individuals consume no more than 20 grams of carbohydrates a day. The diet consists of pure protein and fats. There is no fruit, bread, grains, starchy vegetables, or dairy products other than cheese, cream, or butter. This phase is not suitable for children, pregnant women, or anyone with kidney disease.
On-going Weight Loss. After the first phase, individuals continue to lose weight while they increase carbohydrate levels by five grams each day.
Premaintenance. When individuals get close to their weight goal, they add another 10 grams of carbohydrates per day as long as they do not begin to gain weight. Weight loss is very slow at this time, but the individual is now getting used to maintenance.
Maintenance. Lifetime maintenance is usually between 40 and 100 grams of carbohydrates a day, depending on steady weight level.

Anyone who chooses this diet should prefer fish or soy products to meat as protein sources. Fish may reduce leptin, a hormone associated with fat storage and heart diseases, and would be the best protein source. People on this diet should also choose monounsaturated fats (as in olive oil) over saturated fats or trans-fatty acids fat. Patients often need supplements, at least a multivitamin and possibly calcium, chromium, omega-3 fatty acids (found in fish oil), and other supplements.

The South Beach and Zone diets encourage healthy fats. They also allow certain carbohydrates. For example the Zone uses healthy carbohydrates (vegetables and dried beans) and unsaturated fats. The South Beach diet uses carbohydrates that have a lower impact on blood sugar levels. This is called a low-glycemic index. Low-glycemic foods include barley, dried bean and peas, milk, strawberries, and apples. High-glycemic foods include refined grains, white bread, white potatoes, and bananas and other tropical fruits. The glycemic index was developed for use in diabetes -- not for weight loss. Nevertheless, there is some evidence that foods with low glycemic indexes may produce a feeling of fullness and so discourage further eating. As with any high-protein diets, people at risk for kidney stones, or those who have other kidney problems, should avoid these plans.

Replacing fats and sugars with substitutes may help many people who have trouble maintaining weight. In fact, in one 2003 study, people with type 2 diabetes used the artificial sweetener sucralose and a beta-glucan fat substitute (derived from oats) as part of a low-calorie diet. At the end of the 4 weeks, they achieved better weight, glucose control, and HDL levels than those on a standard diabetic diet.

Fat Substitutes. Fat substitutes added to commercial foods or used in baking deliver some of the desirable qualities of fat, but do not add as many calories. It should be stressed that eliminating all fats from a diet can be harmful to general health.

Fat substitutes include the following:

Stanols. Stanols are plant compounds used in margarines (Benecol, Take Control). Benecol is derived from pine bark and Take Control from soybeans. Two servings a day of either brand, as part of a low-fat, diet can lower LDL and total cholesterol by impairing its absorption in the intestinal tract. Some studies have reported that the use of stanols can allow lower doses of statins (cholesterol lowering medications). Stanols do not appear to block absorption of fat-soluble nutrients or vitamins, as olestra does.
Olestra (Olean) passes through the body without leaving behind any calories from fat. Studies suggest that it improves cholesterol levels and helps people lose weight when it is used to replace a third of normal dietary fats. (Note that simply adding snacks containing olestra does not appear to have any effect on cholesterol or weight loss.) Early reports of cramps and diarrhea after eating food containing olestra have not proven to be significant. Of greater concern is the fact that even small amounts of olestra deplete the body of certain vitamins and nutrients that may help protect against serious diseases, including cancer. The FDA requires that the missing vitamins be added back to olestra products, but not other nutrients. The side health effects, if any, are unknown.
Beta-glucan is a soluble fiber found in oats and barley. Products using this substance (e.g., Nu-Trim) may reduce cholesterol and have additional health benefits.

A number of other fat-substitutes are also available. Although studies to date are not showing any significant side effects, these products' effect on weight control is uncertain, since many of the products containing them may be high in sugar.

Artificial Sweeteners. Many artificial or low-calories sweeteners are available. A 2002 study confirmed that people who consumed artificial sweeteners and reduced their sugar intake weighed less over time than those who took in similar types and amounts of drinks and food containing sugar. It should be noted that using these artificial sweeteners should not give dieters a license to increase their fat intake. Studies indicate that consuming some sugar is not a significant contributor to weight gain, as long as the total amount of calories in the diet is under control. There is some public concern about chemicals used to produce many of these sweeteners, and the side effects seen in studies using rats. Natural low-calories sweeteners are available that may be more acceptable to many people.

Saccharin (Sugar Twin, Sweet n' Low, Sucaryl, and Featherweight). Saccharin has been used for years. Some studies found that large amounts of saccharin cause bladder cancer in rats. However, the rats were fed huge amounts that do not apply to human diets. Currently there is no evidence that saccharin causes cancer in humans.
Aspartame (Nutra-Sweet, Equal, NutraTase). Aspartame has come under scrutiny because of rare reports of nervous system disorders, including headaches or dizziness, associated with its use. People with phenylketonuria (PKU), a genetic condition, should not use it. Studies have not reported any serious health dangers, but some people may be sensitive to it.
Sucralose (Splenda). Sucralose has no bitter aftertaste and works well in baking, unlike other artificial sweeteners. It is made from real sugar by replacing part of the sugar with chlorine. Some people are concerned because chlorinated molecules used in major industrial chemicals have been associated with cancer and birth defects. Over 100 studies have been conducted on sucralose over a 20-year period, with no reports of such risks.
Acesulfame-potassium (Sweet One, SwissSweet, Sunette). It has been used in the U.S. since 1988 with no reported side effects.
Neotame (Neotame). Neotame is a synthetic variation of aspartame, but was developed to avoid its side effects. The association with aspartame has raised some concerns. Studies to date have reported no effects that would cause alarm, and it appears to be safe for general consumption.
D-tagatose (Tagatose). This reduced-calorie sweetener is made from lactose, which is the sugar found in dairy products and other foods. It may be especially beneficial for people with type 2 diabetes. It may also have additional benefits that help the intestinal tract.
Alitame (Aclame) is formed from amino acids, the building blocks of proteins. It has the potential to be used in all products that contain sugar, including baked goods.
Stevioside (Stevia). This is a natural sweetener derived from a South American plant. It is available in health food stores. People with diabetes should avoid alcohol-based forms. It has not been carefully tested.

Other sugar substitutes being investigated include glycyrrhizin (derived from licorice) and dihycrochalcone (derived from citrus fruits).

Some studies have reported good success with meal replacement beverages (Slim-Fast, Sweet Success). They contain major nutrients needed for daily requirements. Each serving typically contains between 200 - 250 calories and replaces one meal. (Note: Using them for all meals reduces calories to a severe extent and can be harmful.)

One study reported that most subjects who had undergone a 12-week weight loss program and then used Ultra Slim Fast supplements as directed for maintenance kept off more than half their weight loss after more than 3 years. A quarter of the subjects were still losing weight.

Medical evidence suggests that a diet rich in magnesium could reduce a person's risk of metabolic syndrome, a cluster of problems including obesity, high blood pressure, and high cholesterol. Metabolic syndrome can lead to diabetes and heart disease. A long-term study of thousands of Americans found that the risk for metabolic syndrome decreased in those who consumed the most magnesium from meals. The findings were published in the journal Circulation.

Commercial and Non-Profit Support Programs for Weight Loss. There are many different types of weight-loss program. (This report cannot address all of the many commercial and nonprofit weight-loss programs currently available, nor can it assess their claims.)

Taking off Pounds Sensibly (TOPS), a nonprofit support organization with many local chapters, is one of the least expensive programs, costing $20 a year.

Most of the commercial programs such as Weight Watchers, Jenny Craig, and NutriSystem offer individual or group support, lifestyle changes and packaged meals. These programs tend to be expensive. There are few well-conducted studies on these programs. One 2003 study reported modest weight loss over 2 years with Weight Watchers compared to a self-help program. There were no differences in heart risk factors.

Cognitive Behavioral Approaches. Most support programs use some form of cognitive-behavioral methods to change the daily patterns associated with eating. They are very useful for preventing relapse after initial weight loss. The following is a typical approach:

The patient first records in a diary all activity related to eating patterns, including the times of day, length of meal, emotional states, companions, and, of course, the kind and amounts of food eaten. Most people -- even professional dieticians, according to one study -- tend to underreport their daily calorie intake. However, writing it down is still a good method for increasing a person's awareness of eating patterns. (One patient said that recording circumstances surrounding relapses was a particularly valuable guide for understanding the stresses leading to her own eating behaviors.)
The patient reviews the diary with a therapist or group to set realistic goals and identify patterns that the patient can change. For instance, if food is normally eaten while watching television, then the patient may be advised to eat in another room instead.
Good eating habits are reinforced by rewards. These rewards are other pleasures that substitute the high calorie consumption and sedentary activities.

Behavioral modification has been shown to be helpful particularly for people who have an overly strong response to the taste, smell, and appearance of food. It also may be useful for binge eaters.

Stress-Reduction Techniques. Stress reduction and relaxation techniques may be helpful for some people with obesity, such as those whose weight is related to night-eating syndrome. [See In-Depth Report #31: Stress.]

Changing Sedentary Habits. Making even small changes in physical activity can expend energy. For example, simply getting up to turn the TV on and off instead of using the remote, and standing (instead of sitting) while talking on the phone may help a person lose up to five pounds a year. Other suggestions include cooking one's own food (instead of eating take-out or fast food), walking to as many places as possible, using stairs instead of escalators or elevators, and gardening. Even fidgeting may be helpful in keeping pounds off, and, in one study, chewing gum increased energy expenditure.

No one should rely on such mild activities, however, for serious weight loss. Only high levels of physical activity -- not just using up energy -- help prevent obesity.

Approach to Exercise. Exercise, which replaces fat with muscle, is the critical companion for any weight control program. In a one-year study, women who regularly averaged 3.5 days (176 minutes) of exercise each week lost significantly more weight than women who did not exercise regularly. Women who exercised more than 195 minutes a week lost nearly 7% of their abdominal fat.

People who exercise are more apt to stay on a diet plan. Exercise improves psychological well-being and replaces sedentary habits that usually lead to snacking. Exercise may even act as a mild appetite suppressant. Moreover, exercise improves overall health even with modest weight loss. In support of this, a British study found that overweight fit individuals had half the death rate of unfit trim individuals.

Be aware, however, that the pounds won't melt off magically. Losing significant weight requires both intensive exercise and calorie restriction. In addition, if a person exercises but doesn't diet, any actual pounds lost may be minimal, because denser and heavier muscle mass replaces fat. Nonetheless, regardless of weight loss, a fit body will look more toned and be healthier. In addition, exercise benefits the heart even with modest weight loss.

The following are some suggestions and observations on exercise and weight loss:

The more strenuous the exercise, the better the chances for short-term and long-term success. With intense exercise, the metabolism continues to burn calories before returning to its resting level. This state of elevated metabolism can last for as little as a few minutes after light exercise to as long as several hours after prolonged or heavy exercise.
Of the standard aerobic machines, the treadmill burns the most calories. It may be particularly effective when used in short multiple bouts during the day. In fact, frequent exercise sessions as short as 10 minutes in duration (about four times a day) may be the most successful exercise program for obese people.
Resistance, or strength, training is excellent for replacing fat with muscles. It should be performed two or three times a week.
As people slim down, their initial level of physical activity becomes easier and they burn fewer calories per mile of walking or jogging. The rate of weight loss slows down, sometimes discouragingly so, after an initial dramatic head start using diet and exercise combinations. People should be aware of this phenomenon and keep adding to their daily exercise program.
As people age, they also need to exercise more to keep off the same amount of weight.
Changes in fat and muscle distribution may differ between men and women as they exercise. Men tend to lose abdominal fat (which lowers their risk for heart disease faster than reducing general body fat). Exercise, however, does not appear to have the same effect on weight distribution in women. In one interesting study, women in aerobic and strength training programs lost fat in their arms and trunk, but did not gain muscle tissue in these regions.

Warning Note. Because obesity is one of the risk factors for heart disease and diabetes, anyone who is overweight must discuss their exercise program with a doctor before starting. Sudden demanding exercise, in such cases, can be very dangerous. [See In-Depth Report #29: Exercise.]

Medications

There are several different drugs used for weight loss. Unless specifically instructed by a doctor, people should use non-drug methods for losing weight. Except under rare circumstances, pregnant or nursing women should never take diet medications of any sort, including herbal and over-the-counter remedies.

A 2001 study reported that 7% of American adults use nonprescription weight-loss products. People must be cautious when using any weight-loss medications, including over-the counter diet pills and herbal or so-called natural remedies. Buying unverified products over the Internet can be particularly dangerous.

Green tea. Perhaps the best alternative advice for people who are overweight is to drink tea. Studies have indicated that regular tea drinking is associated with lower weight, particularly in people who drink it for years. Green tea specifically has been associated with increased energy expenditure. One study reported that people who took a green tea extract (Exolise) lost weight and reduced their waist size. Better evidence is needed to confirm the results on this supplement.

Thermogenic Approach to Weight Loss. An approach to weight loss called thermogenic (also hepatothermic) therapy is based on the idea that certain natural compounds have properties that enable the liver to increase energy in the cells and stimulate the metabolism. Theoretically, the result would be fat loss. Among the natural substances used in such products are EPA-rich fish oil, sesamin, hydroxycitrate, pantethine, L-carnitine, pyruvate, aloe vera, aspartate, chromium, coenzyme Q10, green tea polyphenols, aloe vera, DHEA derivatives, cilostazol, diazoxide, and fibrate drugs.

Nearly all the current over-the-counter dietary aids contain some combination of these ingredients. There is no evidence that any of these ingredients can produce weight loss, and some may even have harmful effects.

Chromium is a common ingredient in many diet supplements (e.g., Xenadrine, Dexatrim, Acutrim Natural, Twinlab Diet Fuel). It is claimed to specifically promote fat loss, rather than lean muscle loss. Some evidence suggests that niacin-bound chromium may improve insulin sensitivity. On the negative side, animal studies have suggested that chromium may have damaging effects on genetic materials in cells. This could cause sterility.

Ephedra, Ephedrine, and Ma Huang. The FDA does not allow the sale of drugs that contain ephedrine. In May 2004, the FDA banned the sale of dietary supplements that contain ephedra (also called Ma Huang). Ephedra has been linked to serious side effects, including strokes and heart attacks.

Brazilian Diet Pill. The US Food and Drug Administration (FDA) is warning consumers not to buy a product known as the "Brazilian diet pill." This product is labeled as a dietary supplement, but contains several chemicals found in powerful prescription drugs. The products are also known as Emagrece Sim and Herbathin dietary supplements.

Conjugated Linoleic Acid (CLA). Conjugated linoleic acid is found in many dietary products (e.g., Biosculpt Liquid, Body Success, GNC Optibolic Body Answers Dietary Formula). There is no evidence that it produces weight loss. Furthermore, there is some concern that CLA might increase insulin resistance and a dangerous inflammatory response in people with obesity.

Tiratricol. Over-the-counter products containing tiratricol, a thyroid hormone, have been sold for weight loss. Such products may increase the risk for thyroid disorders, heart attack, and stroke.

Laxative Actions in Natural Substances. Many dietary herbal teas contain laxatives, which can cause gastrointestinal distress, and, if overused, may lead to chronic pain, constipation, and dependency. In rare cases, dehydration and death have occurred. Some laxative substances found in teas include senna, aloe, buckthorn, rhubarb root, cascara, and castor oil.

Guar Gum. Some fiber supplements containing guar gum have also caused obstruction of the gastrointestinal tract.

Chitosan. Chitosan, a dietary fiber from shellfish, prevents a small amount of fat from being absorbed in the intestine. Well-conducted studies, however, have not found it to be effective. Products containing it include Cheat & Lean Fat Blocker, Natrol, Chroma Slim, and Enforma. People who are allergic to shellfish should not take these supplements.

Plantain. Dietary remedies that list the ingredient plantain may contain digitalis, a powerful chemical that affects the heart. NOTE: This substance should not be confused with the harmless banana-like plant also called plantain.

Orlistat (Xenical) can help about one-third of obese patients with modest weight loss, and can assist in long-term maintenance of weight loss. It works by slowing the absorption of fat (by about 30%) in the intestine. Studies indicate that between 50 - 80% of patients can achieve weight loss of 5% or greater, depending on other lifestyle changes. However, many people regain a significant portion of this weight back within 2 years. It does not work for all patients, however. In one survey of patients who took it, 10% gained weight or did not lose any, and 43% lost less than 5%. Nevertheless, orlistat may delay or even prevent the onset or progression of diabetes and improve cholesterol levels, regardless of weight loss.

The drug can cause gastrointestinal problems and may interfere with absorption of the fat-soluble vitamins A, D, and E and other important nutrients. The most unpleasant side effect is oily leakage of feces from the anus. Restricting fats can reduce this effect. People with bowel disease should probably avoid it. In spite of these side effects, most patients are able to tolerate this agent.

In February 2007, the FDA approved an over-the-counter (OTC) version of orlistat. It will be sold under the name alli, and will be available at half the prescription strength of Xenical. Those eager to use the new pill should consider its cost and modest benefits compared with its side effects, most commonly oily diarrhea. This pill, which prevents fat absorption from food, also increases the risk of not absorbing important nutrients from food while using it. The FDA recommends taking a daily multivitamin supplement when using alli.

Sibutramine (Meridia) helps balance the brain chemicals serotonin and norepinephrine. This helps increase metabolism, causes a feeling of fullness, and increases energy levels. It may be particularly useful for binge-eaters. Studies indicate that sibutramine is effective in achieving weight loss, although the weight loss slows considerably after the first 3 months. The drug also appears to improve cholesterol and lipid (fat) levels, and may have other effects that benefit the heart.

Side effects of sibutramine are common. They include dry mouth, constipation, and insomnia. In one study, almost half the patients dropped out as a result of these side effects. There have been reports of increases in heart rate and blood pressure while taking this medication, although a 2001 study indicates that blood pressure stabilizes over time.

At this time, people who have a history of high blood pressure, stroke, heart disease, or arrhythmias should not take this drug. People taking decongestants, bronchodilators (such as for asthma), monoamine oxidase inhibitors, or serotonin reuptake inhibitors should also avoid sibutramine.

Phentermine and Other Sympathomimetics. Sympathomimetics are drugs that act like the stress hormone (and chemical messenger) norepinephrine. These medications act as stimulants in the brain. Some are approved for treating obesity, but only for short-term use. They include:

Phentermine (Ionamin, Adipex-P, Fastin)
Benzphetamine (Didrex)
Phendimetrazine (Adipost, Bontril, Melfiat, Plegine, Prelu-2, Statobex)

Phentermine is the most commonly prescribed appetite suppressant, and is less expensive than orlistat or sibutramine. Its effects are not long lasting, however. It can also raise blood pressure. In addition, phentermine is associated with depression, which is already a problem in many cases of obesity. A combination (Phen-Pro) containing phentermine and the antidepressant fluoxetine (Prozac) is being investigated to help reduce this problem. Note: Neither phentermine nor such combinations are associated with the heart problems linked to the previous phentermine combination known as Fen-Phen (phentermine and fenfluramine).

Amphetamines. The amphetamines dextroamphetamine (Dexedrine), methamphetamine (Desoxyn), and phenmetrazine (Pleudin) are powerful stimulants. They were used most often in the past but are no longer prescribed for weight loss. These drugs improve mood and produce some modest weight loss over the short term, but carry serious risks of addiction, agitation, and insomnia.

Rimonabant. Rimonabant (Accompli) belongs to a new class of drugs called selective CB1 blockers. The drug is designed to block receptors in the brain associated with the regulation of eating. Rimonabant also targets receptors in fat tissue. The Rimonabant in Obesity-Lipids (RIO-Lipids) study looked at how rimonabant affected metabolic risk factors in high-risk overweight or obese patients with blood fat disorders. The study involved more than 1,000 participants. The findings, published in the November 2005 New England Journal of Medicine, said that people who took the drug significantly reduced their body weight and size of their waist.

Earlier studies involving the drug reported that obese patients treated with 20 mg of rimonabant lost significantly more weight and inches from their waist than patients who received placebo. The drug also appeared to have beneficial effects on raising HDL ("good") cholesterol levels.

Note: Fake rimonabant has been found for sale on several web sites. Patients should be aware that this drug is still experimental, and rimonabant is not available for sale. Buying and taking counterfeit drugs can have serious health consequences. In addition, an FDA advisory panel in April 2007 rejected the drug, citing fears it may cause psychiatric problems and seizures in some patients.

Axokine. Axokine is a type of drug called a ciliary neurotrophic factor. It signals the brain to suppress one's appetite. It is proving to be effective in achieving weight loss, and also improves cholesterol, lipid, and glucose levels regardless of food intake. It could be particularly helpful for people with type 2 diabetes. Early study results found that severely obese patient who took the drug lost more weight than those who took a dummy pill (placebo). Nearly half (46%) of patients who took the drug lost at least 10 pounds, compared to 5% of those who received the placebo. Study participants tolerated the drug well. There were no reports of serious side effects.

Zonisamide. Zonisamide (Zonegran) is an anti-seizure medication that is also being investigated for weight loss. In one study, patients who took it lost more weight than those on placebo. Zonisamide increases the risk for kidney stones, which can be reduced with increased fluid intake and citrate. It has also been associated with reduced sweating and a sudden rise in body temperature, especially in hot weather. Other side effects include dizziness, forgetfulness, headache, and nausea.

Topiramate. Topiramate (Topamax) is another anti-seizure medication being investigated for weight reduction. Three clinical trials have reported that patients given topiramate lost more weight than those receiving placebo. Weight loss was sustained for up to 1 year. The drug is also being studied for binge-eating disorders associated with obesity.

Other Treatments

Surgical procedures for obesity may be appropriate for some dangerously obese people, and may reduce heart problems and many of the risks associated with obesity. These risks include high blood pressure, sleep apnea, and diabetes. In fact, some evidence suggests that surgery may provide much greater control of weight and diabetes than nonsurgical weight-loss methods. Studies are reporting significant reductions in diabetes, and the need for diabetic medications, after surgery. Other medical conditions that often improve after surgery include heartburn, arthritis, and other joint and circulation problems.

Bariatric surgeries produce weight loss through one of two approaches:

Restrictive Banding Procedures. These procedures restrict the amount of food by closing off parts of the stomach with bands.
Malabsorptive Bypass Procedures. This approach restricts the amount of food and also reduces absorption by using a bypass of parts of the intestine.

The malabsorptive procedures are more successful in achieving weight loss than the banding approach, but they carry a greater risk for nutritional deficiencies.

Most people who have bariatric surgery lose about two-thirds of excess weight within 2 years. In addition, diseases associated with obesity (such as diabetes, high blood pressure, sleep apnea, joint pain, and incontinence) often improve.

Researchers at the Mayo Clinic looked at records from patients who had the surgery between 1990 and 2003. They found that those who had bariatric surgery reduced their risk of cardiovascular events such as a heart attack much more than those who lost weight without surgery. The findings were published in the September 2005 Mayo Clinic Proceedings.

Other studies have shown that even though most patients maintain significant weight loss, the majority regain about to 10% of their weight. Patients must still develop a healthy life style and be calorie conscious after the operation. Follow-up must be life-long.

Any surgical candidate must have failed consistently in losing weight through less invasive methods. Experts recommend bariatric surgery only for the following:

Those whose BMI is above 40 (about 100 pounds overweight)
Those with BMIs of over 35 who have type 2 diabetes or serious obesity-related medical problems
Those with severe obesity that interfered with employment, normal physical activity (e.g., walking), and important relationship

About a third of people who undergo these procedures achieve normal weight, and 80% experience some weigh loss. They are less successful than the bypass procedures, but carry a lower risk of nutritional deficiencies.

Vertical Banded Gastroplasty. Vertical banded gastroplasty (VBG) was the most common restrictive procedure. It involves creating a hole through both stomach walls and sealing the edges with a staple. This narrows the stomach, similar to a funnel, and allows only small amounts of food to pass through.

Laparoscopic Gastric Banding. Laparoscopic gastric banding (the Lap-Band) usually does not require a major incision and avoids some of the major complications of gastric bypass:

It employs an adjustable silicone band that is placed around the upper part of the stomach.
A small balloon-like reservoir attached to the band under the abdominal skin contains saline, which can be added or removed to tighten or loosen the band.
The procedure restricts the amount of food a person can eat and gives the feeling of fullness.

The band is removable, if necessary. Studies to date indicate that the intestinal tract returns to normal afterward. Studies, including those done in the elderly, have reported significant weight loss and improved quality of life with the procedure.

Malabsorptive procedures produce greater weight loss than restrictive procedures. Patients generally achieve about two-thirds of their weight loss within 2 years. Furthermore, in a 2003 study, after standard bypass surgery, 83% of patients with type 2 diabetes experienced normal blood glucose levels and the rest had significant reductions.

Roux-en-Y Gastric Bypass Procedure. This is the most common and successful malabsorptive surgery in the United States. It involves creating a small stomach pouch that serves as a reservoir and restricts food intake. The pouch eventually holds up to 3 ounces of food and has a small outlet that delays emptying and causes a feeling of fullness. Then the surgeon creates a Y-shaped section in the small intestine that attaches to the pouch. This section allows food to bypass the lower stomach and upper part of the intestine. One 2003 study reported that this procedure was associated with significant weight loss, and 80% of patients with type 2 diabetes were able to reduce their medications. A more recent study, published in the March 14, 2006, issue of Archives of Surgery, found that gastric bypass surgery also helps lower the blood pressure of very obese patients.

The procedure produces greater and more sustained weight loss than banding procedures, but it is also more complicated, and carries a higher risk of nutritional deficiencies. Laparoscopy techniques, which are less invasive, are now preferred over open surgery. They achieve equally good results with fewer complications.

Biliopancreatic Diversion. This procedure is more complicated and removes portions of the stomach. The pouch that is created attaches directly to the lower part of the small intestine. It poses a higher risk for nutritional deficiencies than other procedures and is not used as often.

Click the icon to see an image of gastric bypass surgery.

General Side Effects and Complications. Side effects and complications of bariatric procedures are common, and up to 25% of patients require corrective or repeat procedures. After any of these procedures people must chew all their food carefully, and they cannot eat large amounts of food at one time. If patients do not follow these guidelines, they will experience nausea, abdominal distress, or both.

Complications from any bariatric procedure includes the following:

Vomiting: This is the most common complication, and it is most common with banding procedures.
Nutritional deficiencies: There is a strong risk of nutritional deficiencies, particularly with malabsorptive operations. This complication can lead to anemia and increase the risk of bone loss and osteoporosis. Taking enough mineral and vitamin supplements is important after bariatric surgery.
Deep-vein thrombosis: There is a significant risk for deep-vein thrombosis (blood clots in the veins).
Abdominal hernia: This is another common complication. Newer, laparoscopic techniques do not carry this risk, but not all individuals are candidates for this less-invasive approach.
Rapid weight loss after surgery: This complication puts people at high risk for gallstones.
Women who wish to be pregnant should wait until their weight has stabilized. Rapid weight loss and nutritional deficiencies can harm the fetus.

People at highest risk for complications are those with heart or lung problems, severe obesity, and a history of abdominal surgeries. The mortality rate from bariatric surgeries is 0.2%, which is lower than the morality rates from severe obesity itself. Other surgical variations and less invasive techniques using laparoscopy have been developed.

Specific Complications of Restrictive Banding Procedures. Nausea, vomiting, or both occurs in half the patients, and severe heartburn occurs in a third. Device-related complications include band slippage, pouch dilation (widening), or both in nearly a quarter of patients, and obstruction in 12% of patients. Very serious complications are rare, but include blood clots, bleeding, infection, pneumonia, and perforation (tearing) of the stomach.

Specific Complications of Malabsorptive Bypass Procedures. Vomiting often occurs. Nutritional deficiencies occur more often in these procedures. The so-called dumping syndrome is a common unpleasant side effect, which occurs when food waste moves too quickly through the intestine. Symptoms include nausea, weakness, sweating, and faintness (particularly after eating sweets).

Spot Exercising. Anyone seeking to lose weight must expect that the results may not be as cosmetically satisfying as one would wish. Spot exercising (training particular areas of the body) is ineffective in reducing fat in specific locations because exercise draws on fat stores throughout the body. Gimmicky devices such as bust developers, vacuum pants, and exercise belts do absolutely nothing to reduce fat or add bulk in specific locations. Electrical pads wrapped around the waist, arms, or thighs were reported to cause burns and fires.

Cellulite-Removal Creams. Many women try to reduce fat in their thighs (cellulite) with creams that contain aminophylline (Skinny Dip, Thermojetics Body Toning Cream, Smooth Contours). Studies provide no evidence that these creams are effective. Their apparent effect on fat may simply be from narrowing blood vessels and forcing water from the skin, which could be dangerous for people with blood flow problems.

Endermologie. Endermologie uses motorized rollers and regulated suction to smooth out cellulite. In one study, about 28.6% of patients reported improved appearance after using it.

Liposuction. Liposuction eliminates fat in specific areas, such as the abdomen, thighs, buttocks, or knees. Special instruments are inserted through the skin into the pockets and suction is used to move the fat, break it up, and remove it. Small tubes may be used to drain blood and fluid during the first few days. The pain after the operation can be severe and often the skin does not contract, resulting in a flabby look. Complications can include burns from the vibrators, bruising, blood clots, and bleeding. Weight gain generally tends to develop in other locations after the operation. Some doctors are using this procedure in overweight people with diabetes to remove abdominal fat. Although there is no proof that it has an effect on diabetes, some experts believe the procedure deserves attention.

Liposuction is not recommended for major weight loss.

Resources

www.healthierus.gov/dietaryguidelines -- Dietary Guidelines for Americans 2005
www.naaso.org -- North American Association for the Study of Obesity
www.eatright.org -- American Dietetic Association
www.nutrition.gov. -- Nutrition.gov
www.asbs.org -- American Society for Bariatric Surgery
www.cnpp.usda.gov -- Center for Nutrition Policy and Promotion
http://fnic.nal.usda.gov -- Food and Nutrition Information Center
www.americanheart.org -- American Heart Association
www.nationaleatingdisorders.org -- National Eating Disorders Organization
www.aabt.org -- Association for Advancement of Behavior Therapy
www.fda.gov -- Food and Drug Administration
http://win.niddk.nih.gov -- Weight-Control Information Network

References

US Food and Drug Administration FDA Approves Orlistat for Over-the-Counter Use. Rockville, MD: National Press Office; February 7, 2007.

Ogden CL, Carroll MD, Curtin LR, McDowell MA, Tabak CJ, Flegal KM. Prevalence of overweight and obesity in the United States, 1999-2004. Journal of the American Medical Association. 2006; 295:1549-1555.

National Center for Health Statistics. Chartbook on Trends in the Health of Americans. Health, United States, 2005. Hyattsville, MD: Public Health Service. 2005

National Institute of Diabetes and Digestive and Kidney Diseases - Weight-control Information Network. Statistics Related to Overweight and Obesity. Available online.

National Center for Health Statistics. Prevalence of Overweight Among Children and Adolescents: United States, 2003-2004.

Morino M, Toppino M, Bonnet G, Rosa R, et al. Laparoscopic vertical banded gastroplasty for morbid obesity. Assessment of efficacy. Surg Endosc. 2002 Nov;16(11):1566-72.

Brethauer SA, Schauer PR, Chand B. Risks and benefits of bariatric surgery: Current evidence. Cleveland Clinic Journal Of Medicine. 2006 Nov; 73(11): 993-1007.

Rosenthal RJ, Szomstein S, Kennedy CI, et al. Laparoscopic surgery for morbid obesity: 1,001 consecutive bariatric operations performed at The Bariatric Institute, Cleveland Clinic Florida. Obes Surg. 2006 Feb;16(2):119-24.

He K, Liu K, Daviglus ML, et al. Magnesium Intake and Incidence of Metabolic Syndrome Among Young Adults. Circulation. 2006: Published online before print. March 27, 2006.

Chen TY, Smith W, Rosenstock JL, Lessnau KD. A life-threatening complication of Atkins diet. Lancet. 2006 Mar 18;367(9514):958.

Lopez-Jimenez F, Bhatia S, Collazo-Clavell ML, Sarr MG, Somers VK. Safety and efficacy of bariatric surgery in patients with coronary artery disease. Mayo Clin Proc. 2005 Sep;80(9):1157-62.

Sidhaye A, Cheskin LJ. Pharmacologic treatment of obesity. Adv Psychosom Med. 2006;27:42-52.

Fernstrom JD, Courcoulas AP, Houck PR, Fernstrom MH. Long-term changes in blood pressure in extremely obese patients who have undergone bariatric surgery. Arch Surg. 2006 Mar;141(3):276-83.

Despres JP, Golay A, Sjostrom L; Rimonabant in Obesity-Lipids Study Group. Effects of rimonabant on metabolic risk factors in overweight patients with dyslipidemia. N Engl J Med. 2005 Nov 17;353(20):2121-34.

Lanningham-Foster L, Nysse LJ, Levine JA. Labor saved, calories lost: the energetic impact of domestic labor-saving devices. Obes Res. 2003 Oct;11(10):1178-81.

Review Date:
6/14/2007
Reviewed By:
A.D.A.M. Editorial Team: Greg Juhn, M.T.P.W., David R. Eltz, Kelli A. Stacy. Previously reviewed by Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital (4/30/2007).

A.D.A.M. Copyright

adam.com

Magnesium

FitSugar — Wed, 08 Oct 2008 17:35:25 -0700

Overview

Overview
Uses
Dietary Sources
Available Forms
How to Take It
Precautions
Possible Interactions
Supporting Research

HEALTH GUIDE REFERENCE FROM A.D.A.M

Overview

Magnesium is a mineral that is involved in over 300 reactions in the body. It is important for every organ in the body, particularly the heart, muscles, and kidneys. It also contributes to the composition of teeth and bones. Most importantly, it activates enzymes, contributes to energy production, and helps regulate calcium levels as well as copper, zinc, potassium, vitamin D, and other important nutrients in the body.

Magnesium is available in many foods. However, most people in the United States probably do not get as much magnesium as they should from their diet. Magnesium is found in whole unprocessed foods in the diet. However, different methods for calculating amounts of magnesium in foods often lead to conflicting results. In addition, not all foods have been thoroughly analyzed.

Despite the fact that dietary levels of magnesium are often low, actual deficiency of this nutrient is rare. Certain medical conditions, however, can upset the body's magnesium balance. For example, intestinal flu with vomiting or diarrhea can cause temporary magnesium deficiencies. Certain stomach and bowel diseases (such as irritable bowel syndrome or IBS and ulcerative colitis), diabetes, pancreatitis, hyperthyroidism (high thyroid hormone levels), kidney malfunction, and use of diuretics can lead to deficiencies. Too much coffee, soda, salt, or alcohol intake as well as heavy menstrual periods, excessive sweating, and prolonged stress can also lower magnesium levels.

Symptoms of magnesium deficiency may include agitation and anxiety, restless leg syndrome (RLS), sleep disorders, irritability, nausea and vomiting, abnormal heart rhythms, low blood pressure, confusion, muscle spasm and weakness, hyperventilation, insomnia, poor nail growth, and even seizures.

Foods rich in magnesium include unrefined grains, nuts and green vegetables. Green leafy vegetables are particularly good sources of magnesium because of their chlorophyll content.

Uses

Getting enough magnesium may help facilitate the results of conventional treatment for the following conditions:

Asthma and emphysema

A population-based clinical study of over 2,500 children aged 11 - 19 years found that low dietary magnesium intake may be associated with a risk of developing asthma. The same was found in a group of over 2,600 adults aged 18 - 70. In addition, some clinical studies suggest that intravenous and inhaled magnesium can help treat acute attacks of asthma in children aged 6 - 18 as well as adults. However, evidence from other clinical studies report that long-term oral magnesium supplementation does not lead to improved control in adult asthma.

Attention deficit/hyperactivity disorder (ADHD)

Some experts believe that children with attention deficit/hyperactivity disorder (ADHD) may be exhibiting the effects of mild magnesium deficiency (such as irritability, decreased attention span, and mental confusion). In one clinical study of 116 children with ADHD, 95% were magnesium deficient. In a separate clinical study, 75 magnesium-deficient children with ADHD were randomly assigned to receive magnesium supplements in addition to standard treatment or standard treatment alone for 6 months. Those who received magnesium demonstrated a significant improvement in behavior, whereas those who received only standard therapy without magnesium exhibited worsening behavior.

These results suggest that magnesium supplementation, or at least high amounts of magnesium in the diet, may prove to be beneficial for children with ADHD.

Depression

Major depression is a mood disorder characterized by a sense of inadequacy, despondency, decreased activity, pessimism, and sadness where these symptoms severely disrupt and negatively affect the person's life. Clinical studies have found that dietary deficiencies of magnesium, coupled with excess calcium and stress may cause many cases of other related symptoms, including agitation, anxiety, irritability, confusion, sleeplessness, headache, confusion, and hyperexcitability.

Diabetes

Type 2 diabetes is associated with low levels of magnesium in the blood. A large clinical study of over 2000 people found that higher dietary intake of magnesium may protect against development of type 2 diabetes. Magnesium was found to improve insulin sensitivity in these people, reducing the risk of developing type 2 diabetes. Other clinical studies have found similar results, especially in the elderly. Magnesium deficiency in diabetic patients may decrease their immunity, making them more susceptible to infections and illnesses.

Fibromyalgia

Results of a preliminary clinical study including 24 people with fibromyalgia suggest that a proprietary tablet containing both malic acid and magnesium may improve pain and tenderness associated with this health condition when taken for at least 2 months. Others suggest that the combination of calcium and magnesium may be helpful for some people with fibromyalgia.

However, a review article evaluating many studies concluded that magnesium with malic acid offered no relief for those with this condition. Whether these supplements ease the discomfort of fibromyalgia may vary from one individual to the next. More studies are needed.

Heart disease

Magnesium is essential to heart health. This mineral is particularly important for maintaining a normal heart rhythm and is often used by physicians to treat irregular heartbeat (arrhythmia). People with congestive heart failure (CHF) are often at particular risk for developing an arrhythmia. For this reason, your doctor may determine that magnesium should be a part of the treatment of CHF.

Results of studies using magnesium to treat heart attack survivors, however, have been inconsistent. Some studies have reported reduced death rates as well as fewer arrhythmias and improved blood pressure when magnesium is used as part of the treatment following a heart attack. In a hospital setting, if you have had a heart attack, the doctor will determine if magnesium supplementation, either intravenously or orally, is necessary.

High blood pressure

Eating low-fat dairy products along with lots of fruits and vegetables on a regular basis is associated with lower blood pressure. All of these foods are rich in magnesium as well as calcium and potassium. Singling out which of these nutrients is responsible for lowering blood pressure is difficult. A large clinical study of over 8,500 women found that a higher intake of dietary magnesium may decrease the development of high blood pressure in women.

Human immunodeficiency virus (HIV)

Several clinical studies suggest that between 30 - 65% of people with human immunodeficiency virus (HIV) have low levels of magnesium. Those with low levels may be more likely to complain of fatigue (excessive tiredness), diminished energy, and confusion. Whether magnesium supplements would improve these symptoms in people with HIV, however, has not been evaluated.

Intravenous magnesium is sometimes used by doctors to lower high blood pressure in a hypertensive crisis. Using magnesium supplements (even oral ones) for high blood pressure should only be done under the supervision of a competent health care provider.

Inflammatory bowel disease (IBD)

People with inflammatory bowel disease (IBD, particularly ulcerative colitis) may have low magnesium levels. In addition, there is some early clinical evidence that dietary magnesium supplements may be of some value for preventing IBD flare-ups.

Infertility and miscarriage

A small clinical study of infertile women as well as women with a history of miscarriage found that low levels of magnesium may impair reproductive function and increase the risk for miscarriage. The authors of the study suggest that one aspect of the treatment of infertility (particularly in women with a history of miscarriage) should include magnesium along with selenium. More research in this area is needed.

Menopause

Because magnesium improves the absorption of calcium from the gastrointestinal tract, some practitioners suggest that women take calcium and magnesium together at a ratio of 2:1, particularly around the time of menopause. This helps prevent osteoporosis (loss of bone mass).

In addition, as estrogen levels drop during menopause, magnesium levels seem to diminish as well. For this reason, magnesium may also help to relieve some menopausal symptoms such as hot flashes, depression, and insomnia. More research is needed.

Migraine headache

Magnesium levels tend to be lower in those with migraine headaches, including children and teenagers, when compared to those with tension headaches or no headaches at all. In addition, a few clinical studies suggest that magnesium supplements may decrease the length of time that one suffers from a migraine and reduces the amount of medication needed.

Some experts suggest that oral magnesium may be an appropriate alternative to prescription medication for people who suffer from migraine headaches. Other experts suggest that combining magnesium with the herb feverfew along with vitamin B2 (riboflavin) may be particularly helpful when you have a headache.

On the other hand, magnesium sulfate seems to be less effective than prescription medications for preventing migraines in those who have 3 or more headaches per month. The only exception to this may be women who get migraine headaches around the time of their menstrual period. In addition, magnesium supplements may prove to be a welcome option for migraine sufferers who cannot tolerate medications due to side effects or who can't take migraine medications due to pregnancy or heart disease. These issues are under scientific investigation.

Osteoporosis

Calcium, vitamin D, magnesium, and other micronutrient deficiencies are believed to play a role in the development of osteoporosis. Adequate intake of calcium, magnesium, and vitamin D coupled with overall proper nutrition and weight-bearing exercise throughout childhood and adulthood are the primary preventive measures for this condition, in both men and women.

Preeclampsia and eclampsia

Intravenous magnesium sulfate is commonly used to prevent complications from preeclampsia and eclampsia. Preeclampsia is a condition characterized by a sharp rise in blood pressure during the third trimester of pregnancy. Women with preeclampsia may develop seizures, which is then called eclampsia. Magnesium, administered in the hospital intravenously (IV or into the veins), is the treatment of choice to prevent or treat seizures associated with eclampsia.

Premenstrual Syndrome (PMS)

Scientific evidence and clinical experience suggest that magnesium supplements may help relieve symptoms associated with PMS, particularly bloating, insomnia, leg swelling, weight gain, and breast tenderness. Preliminary information suggests that magnesium may be helpful for alleviating mood swings as well.

Stroke

Population-based information suggests that people with low magnesium in their diet may be at greater risk for stroke. Some preliminary clinical evidence suggests that magnesium sulfate may be helpful in the treatment of a stroke or transient ischemic attack (TIA, or a temporary disturbance of blood supply to an area of the brain). More research is needed to know for certain if use of this mineral following a stroke or TIA is helpful.

Other

A small clinical study including only 10 patients found that magnesium improved insomnia related to restless legs syndrome (a disorder characterized by uncomfortable sensations in the legs, which are worse during periods of inactivity or rest or while sitting or lying down). In another study including 42 patients undergoing abdominal hysterectomy, those who received intravenous magnesium sulfate before and after surgery required fewer pain-killers, experienced less discomfort, and slept better after surgery compared to those who received placebo.

Magnesium levels were also reported lower in alcoholics and those addicted to heroin. More studies are needed in using magnesium for addictive disorders.

Dietary Sources

Rich sources of magnesium include tofu, legumes, whole grains, green leafy vegetables, wheat bran, Brazil nuts, soybean flour, almonds, cashews, blackstrap molasses, pumpkin and squash seeds, pine nuts, and black walnuts. Other good dietary sources of this mineral include peanuts, whole wheat flour, oat flour, beet greens, spinach, pistachio nuts, shredded wheat, bran cereals, oatmeal, bananas, and baked potatoes (with skin), chocolate, and cocoa powder. Many herbs, spices, and seaweeds supply magnesium, such as agar seaweed, coriander, dill weed, celery seed, sage, dried mustard, basil, cocoa powder, fennel seed, savory, cumin seed, tarragon, marjoram, poppy seed.

Available Forms

Magnesium is available in many forms. Recommended types include magnesium citrate, magnesium gluconate, and magnesium lactate, all of which are more easily absorbed into the body than other forms such as magnesium oxide. Time-release preparations may improve magnesium absorption. Ask your health care provider.

Other familiar sources of magnesium are magnesium hydroxide (often used as a laxative or antacid) and magnesium sulfate (generally used orally as a laxative or in multivitamins, or added to a bath). Some magnesium can be absorbed through the skin.

How to Take It

Be sure to check with your health care provider before taking magnesium supplements and before considering them for a child. Under certain circumstances, such as certain heart arrhythmias and preeclampsia, a doctor will have magnesium administered intravenously (into the veins) in the hospital.

It is a good idea to take a B vitamin complex, or a multivitamin containing B vitamins, because the level of vitamin B6 in the body determines how much magnesium will be absorbed into the cells.

Dosages are based on the dietary reference intakes (DRIs) issued from the Food and Nutrition Board of the United States Government's Office of Dietary Supplements, part of the National Institutes of Health.

Pediatric

For infants and children up to 3 years of age: The recommended dietary intake is 40 - 80 mg daily.

For children 4 - 6 years of age: The recommended dietary intake is 120 mg daily.

For children 7 - 10 years of age: The recommended dietary intake is 170 mg daily.

For adolescent and adult males: The recommended dietary intake is 270 - 400 mg daily.

For adolescent and adult females: The recommended dietary intake is 280 - 300 mg daily.

For pregnant females: The recommended dietary intake is 320 mg daily.

For breast-feeding females: The recommended dietary intake is 340 - 335 mg daily.

Magnesium needs increase during times of protein synthesis, such as pregnancy, recovering from surgery and illnesses, and athletic training.

Precautions

Because of the potential for side effects and interactions with medications, dietary supplements should be taken only under the supervision of a knowledgeable health care provider. Individuals with heart or kidney disease should not take magnesium supplements except under the guidance of a qualified health care provider.

It is extremely rare to overdose on magnesium from food alone. However, people who consume excessive amounts of milk of magnesia (as a laxative or antacid) or epsom salts (as a laxative or tonic) may overdose on this magnesium, especially if they have kidney problems. Too much magnesium can cause serious health problems, including nausea, vomiting, severely lowered blood pressure, slowed heart rate, deficiencies of other minerals, confusion, coma, and even death. More common side effects from magnesium include upset stomach and diarrhea.

Magnesium competes with calcium for absorption and can cause a calcium deficiency if calcium intake levels are already low. Magnesium may be depleted from the body due to certain medications. Medications that may decrease magnesium levels in the body include chemotherapy drugs, diuretics, digoxin (Lanoxin), hormonal supplementation, steroids, and certain antibiotics.

Possible Interactions

If you are currently being treated with any of the following medications, you should not use magnesium without first talking to your health care provider.

Antibiotics --The absorption of quinolone antibiotics, such as ciprofloxacin (Cipro) and moxifloxacin (Avelox), tetracycline antibiotics, including tetracycline (Sumycin), doxycycline (Vibramycin), and minocycline (Minocin), and nitrofurantoin (Macrodandin), may be diminished when taking magnesium supplements. Therefore, magnesium should be taken 1 hour before or 2 hours after taking these medications to avoid interference with absorption.

Blood Pressure Medications, Calcium Channel Blockers --Magnesium may increase the likelihood of negative side effects (such as dizziness, nausea, and fluid retention) from calcium channel blockers (particularly nifedipine or Procardia) in pregnant women. Other calcium channel blockers include amlodipine (Norvasc), diltiazem (Cardizem), felodipine (Plendil), and verapamil (Calan).

Diabetic Medications -- Magnesium hydroxide, commonly found in antacids such as Alternagel, may increase the absorption of glipizide and glyburide, medications used to control blood sugar levels. Ultimately, this may prove to allow for reduction in the dosage of those medications.

Digoxin -- It is important that normal levels of magnesium be maintained while taking digoxin (Lanoxin) because low blood levels of magnesium can increase adverse effects from this drug, including heart palpitations and nausea. In addition, digoxin can lead to increased loss of magnesium in the urine. A health care provider will follow magnesium levels closely to determine whether magnesium supplementation is necessary in individuals taking digoxin.

Diuretics -- Two types of diuretics known as loop (such as furosemide or Lasix) and thiazide (including hydrochlorothiazide) can deplete magnesium levels. For this reason, doctors who prescribe diuretics may consider recommending magnesium supplements as well.

Hormone Replacement Therapy for menopause -- Magnesium levels tend to decrease during menopause. Clinical studies suggest, however, that hormone replacement therapy may help prevent the loss of this mineral. Postmenopausal women or those taking hormone replacement therapy should talk with a health care provider about the risks and benefits of magnesium supplementation.

Levothyroxine -- There have been case reports of magnesium containing antacids reducing the effectiveness of levothyroxine, which is taken for an under active thyroid. This is important because many people take laxatives containing magnesium without letting their doctor know.

Penicillamine -- Penicillamine, a medication used for the treatment of Wilson's disease (a condition characterized by high levels of copper in the body) and rheumatoid arthritis, can inactivate magnesium, particularly when high doses of the drug are used over a long period of time. Even with this relative inactivation, however, supplementation with magnesium and other nutrients by those taking penicillamine may reduce side effects associated with this medication. A health care provider can determine whether magnesium supplements are safe and appropriate if you are taking penicillamine.

Tiludronate and Alendronate -- Magnesium may interfere with absorption of medications used in osteoporosis, including alendronate (Fosamax). Magnesium supplements or magnesium-containing antacids should be taken at least 1 hour before or 2 hours after taking these medications to minimize potential interference with absorption.

Others -- Aminoglycoside antibiotics (such as gentamicin and tobramycin), thiazide diuretics (such as hydrochlorothiazide), loop diuretics (such as furosemide and bumetanide), amphotericin B, corticosteroids (prednisone or Deltasone), antacids, and insulin may lower magnesium levels. Please refer to the depletions monographs on some of these medications for more information.

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Review Date:
5/14/2007
Reviewed By:
Ernest B. Hawkins, MS, BSPharm, RPh, Health Education Resources; and Steven D. Ehrlich, N.M.D., private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.

A.D.A.M. Copyright

adam.com

Calcium

FitSugar — Wed, 08 Oct 2008 17:35:15 -0700

Overview

Overview
Dietary Sources
Available Forms
How to Take It
Precautions
Possible Interactions
Supporting Research

HEALTH GUIDE REFERENCE FROM A.D.A.M

Overview

Calcium is the most abundant mineral in the body. It is essential for the development and maintenance of strong bones and teeth, the location of about 99% of the body's calcium. Calcium also helps the heart, nerves, muscles, and other body systems work properly. It is probably best known for its effects in preventing osteoporosis. Your body needs several other nutrients in order for calcium to be absorbed and used properly, including magnesium, phosphorous, and especially vitamins D and K.

The best way to get calcium is through food (see Dietary Sources). But although many foods are fortified with calcium, some people may still need to take calcium supplements. In fact, according to the National Institutes of Health, many Americans consume less than half the amount of calcium recommended to build and maintain healthy bones. It is especially important to get enough calcium as you age. Postmenopausal women, people who consume large amounts of caffeine, alcohol, or soda, and those who take corticosteroid medications may need calcium supplements. Calcium deficiency can be found in people with malabsorption problems, such as Crohn's disease, celiac disease, and surgical intestinal resection.

Getting enough calcium can help prevent or treat the following conditions:

Osteoporosis

Calcium is necessary to help build and maintain healthy bones and strong teeth. Studies have shown that calcium, particularly in combination with vitamin D, can help prevent bone loss associated with menopause, as well as the bone loss experienced by older men. If you do not get enough calcium in your diet, taking a supplement may be necessary.

Hypoparathyroidism

People with this condition have underactive parathyroid glands, which are four small glands that sit on the four corners of the thyroid in the neck and produce a hormone that regulates calcium, phosphorous, and vitamin D levels in the body. People with this condition should follow a high-calcium, low-phosphorous diet as prescribed by their doctor. Most often, they will also need to take calcium supplements.

Premenstrual Syndrome (PMS)

One large, well-designed study showed that women who took 1,200 mg of calcium per day reduced their symptoms of PMS by 50%, including headache, moodiness, food cravings, and bloating. A smaller study suggested that calcium may help reduce menstrual pain.

High Blood Pressure

People who do not get enough calcium may be at higher risk for hypertension, and there is some mixed evidence that suggests increasing calcium levels may lower blood pressure slightly. However, not all studies have found that benefit; and researchers aren’t sure whether calcium supplements would have any benefit, or whether it’s the effects of a diet that includes low-fat dairy products (which contain calcium) that is responsible. If you want to try calcium supplements, do not stop taking your blood pressure medication; talk to your doctor and let the doctor determine the proper dose of calcium for you. You may need to take calcium for 6 - 8 weeks before you see any improvement in blood pressure.

Some studies suggest that calcium supplementation may play a role in the prevention of pregnancy-induced high blood pressure and preeclampsia (a combination of high blood pressure, fluid retention, and high levels of protein in the urine that some women develop in the last trimester of pregnancy). However, not all studies show the same benefit. A prenatal vitamin, which provides magnesium, folic acid, and many other nutrients, together with adequate calcium intake through the diet, may lower the risk of developing high blood pressure during pregnancy.

Obesity

Some animal and human studies have found that consuming low-fat dairy products may help you lose or maintain a proper weight. However, researchers aren’t sure whether the calcium in the dairy products affects weight, some other nutrient -- or even a combination of nutrients. In addition, not all studies have found any benefit; and there’s no sound evidence that calcium supplements (as opposed to dairy products) would help in losing weight. More research is needed.

High Cholesterol

Preliminary studies in animals and people suggest that calcium supplements, in the range of 1,500 to 2,000 mg per day, may help to lower cholesterol slightly. From these studies, it appears that calcium supplements (along with exercise and proper diet) may be better at keeping cholesterol at normal levels than at lowering them once cholesterol is already high. More research in this area is needed.

Rickets

Rickets causes softening and weakening of the bone in children. Although virtually eliminated in North America and Western Europe, where milk consumption is common, it still occurs in many parts of the world. Researchers have thought that rickets is caused by a lack of vitamin D; however, a study in 2000 showed that calcium supplementation is an effective treatment.

Other Uses

Stroke -- In a population-based study (one in which large groups of people are followed over time), women who take in more calcium, both through their diet and with supplements, were less likely to have a stroke over a 14-year period. More research is needed.

Colon Cancer -- Although not all studies agree, some show that people who consume higher amounts of calcium, vitamin D, and milk in their diets are less likely to develop colorectal cancer than those who consume low amounts of the same nutrients. But researchers are not sure whether calcium supplements would have the same effect as calcium in the diet, or even whether calcium itself is responsible for the benefit.

Dietary Sources

The richest dietary sources of calcium include cheeses (such as parmesan, Romano, gruyere, cheddar, American, mozzarella, and feta), low-fat dairy products (milk, yogurt), tofu, and blackstrap molasses. Some other good sources of calcium include almonds, brewer's yeast, bok choy, Brazil nuts, broccoli, cabbage, dried figs, kelp, dark leafy greens (dandelion, turnip, collard, mustard, kale, Swiss chard), hazelnuts, oysters, sardines, and canned salmon,.

Foods that are fortified with calcium, such as juices, soy milk, rice milk, tofu and cereals, are also good sources of this mineral.

Available Forms

There are a number of forms of calcium available as dietary supplements. They differ in the amount of calcium they contain, how well they are absorbed by the body, and how much they cost. The two most popular forms are calcium citrate and calcium carbonate.

Calcium citrate: Easily absorbed and digested by the body, particularly in the elderly. It does not contain as much elemental calcium (the amount your body actually absorbs) as calcium carbonate. It is more costly than calcium carbonate, however. Also, calcium citrate should not be used with aluminum-containing antacids (see Possible Interactions).
Calcium carbonate: Less expensive than calcium citrate and contains more elemental calcium. Requires a certain amount of stomach acid to be absorbed, so it is usually taken with a glass of orange juice. Many antacids contain calcium carbonate.

Calcium supplements that are derived from oyster shells, dolomite, and bone meal are best avoided as they may contain lead, a toxic metal (particularly worrisome in children and those with kidney disease) that can harm the brain and kidneys, cause anemia, and raise blood pressure.

How to Take It

Calcium supplements should be taken in small doses (no more than 500 mg at a time -- that’s all your body can absorb in one dose) throughout the day with 6 - 8 cups of water to avoid constipation.

The following are daily dietary recommendations for general health and prevention of disease.

Pediatric

Talk to your pediatrician before giving a child any nutritional supplement.

Infants birth to 6 months: 210 mg
Infants 7 months to 1 year: 270 mg
Children 1 - 3 years: 500 mg
Children 4 - 8 years: 800 mg
Adolescents 9 - 18 years: 1,300 mg

Adult

19 - 50 years: 1,000 mg
51 years and older: 1,200 mg
Pregnant and breastfeeding females under 19 years: 1,300 mg
Pregnant and breastfeeding females 19 years and older: 1,000 mg

For prevention of colon cancer, 1,800 mg per day may be required.

Precautions

Because of the potential for side effects and interactions with medications, dietary supplements should be taken only under the supervision of a knowledgeable health care provider. Total calcium intake, from combined dietary and supplemental sources, should not exceed 2,500 mg per day.

Side effects can include constipation and stomach upset. Very high doses can cause nausea, vomiting, loss of appetite, increased urination, kidney toxicity, confusion, and irregular heart rhythm.

More generally, such high levels of calcium in the body occur when the body produces too much calcium. People with hyperparathyroidism, kidney failure, sarcoidosis, or cancer could be at risk for elevated levels of calcium and should not take calcium supplements.

People with a history of kidney stones should not take calcium supplements. However, some research suggests that calcium in the diet may not increase the risk of kidney stones. If you have or have had kidney stones, talk to your doctor about whether you should restrict calcium in your diet.

Men at risk for prostate cancer should avoid calcium supplements and also talk to their doctor about restricting low-fat dairy in their diets. Several studies have shown that higher intakes of calcium, whether from supplements or dairy products, are associated with greater risk of prostate cancer.

Possible Interactions

If you are currently being treated with any of the following medications, you should not use calcium supplements without first talking to your doctor.

Alendronate -- Calcium may interfere with the absorption of alendronate, a medication used to treat osteoporosis. Calcium-containing products should be taken at least 2 hours before or after alendronate.

Antacids that contain aluminum -- When calcium citrate is taken with aluminum-containing antacids, the amount of aluminum absorbed into the blood may be increased significantly. This is a particular problem for people with kidney disease, for whom the aluminum levels may become toxic.

Blood pressure medications -- Taking calcium with a beta-blocker (such as atenolol) may interfere with blood levels of both the calcium and the beta-blocker. Study results are conflicting, however. Similarly, it has been reported that calcium interferes with calcium channel blockers (such as verapamil), but these study results are also controversial. If you take a beta-blocker or calcium-channel blocker, do not take calcium supplements without your doctor’s supervision.

Cholesterol-lowering medications -- A class of medications known as bile acid sequestrants (including cholestyramine, colestipol, and colesevelam), used to treat high cholesterol, may interfere with normal calcium absorption and increase the loss of calcium in the urine. Supplementation, therefore, with calcium and vitamin D may be recommended by your health care provider.

Corticosteroids -- If you take corticosteroids on a long-term basis, you may need to take calcium supplements.

Digoxin -- High levels of calcium may increase the risk of a toxic reaction to digoxin, a medication used to treat irregular heart rhythms. On the other hand, low levels of calcium cause digoxin to be ineffective. If you take digoxin, your doctor should monitor your calcium levels closely.

Diuretics -- Different types of diuretics interact with calcium in opposite ways.

Thiazide diuretics (such as hydrochlorothiazide) can raise calcium levels in the blood.
Loop diuretics (such as furosemide and bumetanide) can decrease calcium levels.
Amiloride (a potassium-sparing diuretic) may decrease the amount of calcium excreted in the urine (thus increasing calcium levels in the blood), especially in people with kidney stones.

Estrogens -- Estrogens may contribute to an overall increase in calcium blood levels. Taking calcium supplements with estrogens improves bone density significantly.

Gentamicin -- Taking calcium during treatment with the antibiotic gentamicin may increase the potential for toxic effects on the kidneys.

Antibiotics -- Different types of antibiotics interact with calcium.

Quinolones: Calcium can interfere with the body's ability to absorb quinolone antibiotics (such as ciprofloxacin or Cipro; levofloxacin, norfloxacin or Noroxin; and ofloxacin). Take calcium supplements 2 - 4 hours before or after taking quinolone antibiotics
Tetracyclines: Calcium can interfere with the body's ability to absorb tetracycline antibiotics (including doxycycline, minocycline, and tetracycline). Take calcium supplements 2 -4 hours before or after taking quinolone antibiotics.

Anti-seizure medications -- Some seizure medications, such as phenytoin (Dilantin), carbamazepine, phenobarbitol, and primidone, may lower levels of calcium in the body. Some doctors recommend vitamin D along with anti-seizure drugs to try to keep calcium levels up. In addition, you should take doses of calcium and anti-seizure medications at least 2 hours apart, because each interferes with the absorption of the other.

Supporting Research

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Review Date:
6/25/2007
Reviewed By:
Steven D. Ehrlich, N.M.D., private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.

A.D.A.M. Copyright

adam.com

Osteoporosis

FitSugar — Wed, 08 Oct 2008 17:34:56 -0700

In This Report

Highlights
Introduction
Causes
Symptoms
Fractures
Risk Factors
Diagnosis
Lifestyle Changes
Medications
Treatment
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Drug Approvals

In 2007, the Food and Drug Administration (FDA) approved zoledronic acid (Reclast) for postmenopausal osteoporosis treatment. Zoledronic acid is given as an injection once a year. A 2007 study in the New England Journal of Medicine indicated that zoledronic acid can significantly reduce the risk of spine, hip, and other fractures.
In 2007, the FDA approved raloxifene (Evista) for prevention of breast cancer in postmenopausal women with osteoporosis and postmenopausal women at high risk for breast cancer. Raloxifene was previously approved for prevention and treatment of osteoporosis.

Calcium and Vitamin D for Osteoporosis Prevention

In 2007, the Food and Drug Administration proposed allowing manufacturers of food and supplements to put a health claim on their products stating that the combination of calcium and vitamin D can reduce the risk of osteoporosis.
In 2007, the National Osteoporosis Foundation updated its daily intake guidelines to recommend 1,200 mg of calcium, and 800 - 1,000 IU of vitamin D3, for adults age 50 and older.
Calcium plus vitamin D is effective in preventing osteoporosis in people age 50 years and older, according to a 2007 review in the Lancet. The researchers found that a minimum of 1,200 mg of calcium and at least 800 IU of vitamin D per day gave the most protection.

Fosamax: Taking a Break (Without Breaking a Bone)

Women at low risk for fracture may be able to temporarily stop taking alendronate (Fosamax) after 5 years, suggests a 2006 study in the Journal of the American Medical Association.

Antidepressants and Osteoporosis Risk

Selective serotonin reuptake inhibitors (SSRIs), the most commonly used class of antidepressants, may increase the risk for bone loss in both older men and women, according to several studies published in 2007 in the Archives of Internal Medicine. SSRIs include fluoxetine (Prozac), sertraline (Zoloft), and paroxetine (Paxil). The researchers did not find that other types of antidepressants are associated with reduced bone mineral density.

Introduction

Osteoporosis is a disease of the skeleton in which bones become brittle and prone to fracture. In other words, the bone loses density. Osteoporosis is diagnosed when bone density has decreased to the point where fractures occur with mild stress.

The skeleton consists of groups of bones which protect and move the body.

Until a healthy person is around age 40, the process of breaking down and building up bone by cells called osteoclasts and osteoblasts is a nearly perfectly coupled system, with one phase stimulating the other. As a person ages, or in the presence of certain conditions, this system breaks down and the two processes become out of sync. The reasons why this occurs during aging are not clear. Some individuals have a very high turnover rate of bone, some have a very gradual turnover, but the breakdown of bone eventually overtakes the build-up.

The Function of Bones. The skeleton has a dual function:

It provides structural support for muscles and organs.
It also serves as a depot for the body’s calcium and other essential minerals, such as phosphorus and magnesium.

The skeleton holds 99% of the body’s calcium. The remaining 1% circulates in the blood and is essential for crucial bodily functions, ranging from muscle contraction to nerve function to blood clotting.

Bone Turnover: the Breakdown and Growth of Bones. Like other organs in the body, bone tissue is constantly being broken down and reformed again. This turnover is necessary for growth, for repair of minor damage that occurs from everyday stress, and for the maintenance of a properly functioning body. Two essential cells are involved in this process:

Osteoblast cells are produced by bone cells and are the bone builders. They rebuild the skeleton, first by filling in the holes with collagen, and then by laying down crystals of calcium and phosphorus.
Osteoclast cells are formed from certain blood cells and are responsible for the breakdown, or resorption, of the skeleton. These cells dig holes into the bone and release the small amounts of calcium into the bloodstream that are necessary for other vital functions.

Each year, about 10 - 30% of the adult skeleton is remodeled in this way. The bone build up (formation)-break down (resorption) balance is controlled by a complex mix of hormones and chemical factors. If bone resorption occurs at a greater rate than bone build up, your bone loses density and puts you at risk for osteoporosis.

In women, estrogen loss after menopause is associated with rapid resorption and loss of bone density. This group, then, is at highest risk for osteoporosis and therefore for fracture.

There are two primary kinds of osteoporosis: type I and type II:

Type I. Type I, or high turnover, osteoporosis occurs in 5 - 20% of women, most often between the ages of 50 and 75. This is because of the sudden postmenopausal decrease in estrogen levels, which results in a rapid depletion of calcium from the skeleton. This is associated with fractures that occur when the vertebrae compress together, causing a collapse of the spine. It is also associated with fractures of the hip, wrist, or forearm caused by falls or minor accidents. Women have a higher risk for type 1 osteoporosis than men.
Type II. Type II, or low turnover, osteoporosis (also known as age-related or senile osteoporosis) results when the process of resorption and formation of bone are no longer coordinated, and bone breakdown overcomes bone building. (This occurs with age in everyone to some degree.) Type II osteoporosis affects both men and women and is primarily associated with leg and spinal fractures. Older women can have both type I and type II osteoporosis.

Click the icon to see an image of a compression fracture.

What determines the existence of osteoporosis, whether type I or type II, is the amount of calcium left in the skeleton and whether it places a person at risk for fracture. Someone who has exceptionally dense bones to begin with will probably never lose enough calcium to reach the point where osteoporosis occurs, whereas a person who has low bone density could easily develop osteoporosis despite losing only a relatively small amount of calcium.

Secondary osteoporosis is caused by other conditions, such as hormonal imbalances, diseases, or medications (such as corticosteroids or anti-seizure drugs).

Click the icon to see an image of osteoporosis.

Causes

Because the patterns of reforming and resorbing bone often vary from patient to patient, experts believe several different factors account for this problem. Important chemicals (such as estrogen, parathyroid hormone, and vitamin D) and blood factors that affect cell growth are involved with this process. Changes in levels of any of these factors could play a role in the development of osteoporosis.

Although ordinarily associated with women, sex hormones play a role in osteoporosis in both genders, most likely by controlling the birth and duration of life of both osteoclasts (bone breakers) and osteoblasts (bone builders).

Women and Estrogen. Experts are still puzzled by the rapid decline in bone density after menopause, when a woman’s ovaries stop producing estrogen. Estrogen comes in several forms:

The uterus is a hollow muscular organ located in the female pelvis between the bladder and rectum. The ovaries produce the eggs that travel through the fallopian tubes. Once the egg has left the ovary it can be fertilized and implant itself in the lining of the uterus. The main function of the uterus is to nourish the developing fetus prior to birth.

The most potent form of estrogen is estradiol. Estradiol deficiency appears to be a very strong factor in the development of osteoporosis.
The other important but less powerful estrogens are estrone and estriol.

The ovaries produce most of the estrogen in the body, but it can also be formed in other tissues, such as body fat, skin, and muscle. After menopause, some amounts of estrogen continue to be manufactured in the peripheral body fat. Even though the ovaries have stopped producing estrogens directly, they continue to be a source of the male hormone testosterone, which converts into estradiol.

Estrogen may have an impact on bone density in various ways:

Estrogen’s most important effect on osteoporosis appears to be prevention of bone breakdown (resorption). Some research suggests that estrogen may control the life span of osteoclasts, the cells responsible for bone breakdown.
One study reported that part of estrogen’s beneficial actions may involve maintaining normal levels of vitamin D, an important nutrient in bone protection.

Men and Androgens and Estrogen. In men, the most important androgen (male hormone) is testosterone, which is produced in the testes. Other androgens are produced in the adrenal glands. Androgens are converted to estrogen in various parts of a man’s body, including bone.

Click the icon to see an image of the adrenal glands.

Studies have suggested that the loss of estrogen as well as testosterone may contribute to bone loss in elderly men. In one study, elderly men were first given a drug that blocked their normal hormones and then were given estrogen and testosterone patches. When the estrogen patch was removed, the bone breakdown process accelerated. When both patches were removed, the number of the bone-building cells (the osteoblasts) decreased. In other words, both hormones appeared to be integral to bone function in men.

Low levels of vitamin D and high levels of parathyroid hormone (PTH) are associated with hip fracture in women after menopause:

Vitamin D is a vitamin with hormone-like properties. It is essential for the absorption of calcium into the bone and for normal bone growth. Lower levels result in impaired calcium absorption, which in turn causes an increase in PTH.
Parathyroid hormone (PTH) is produced by the parathyroid glands. These are four small glands located on the surface of the thyroid gland. They are the most important regulators of calcium levels in the blood. When calcium levels are low, the glands secrete more PTH, which then increases blood calcium levels. High persistent levels of PTH stimulate bone resorption (bone loss).

Click the icon to see an image of the benefits of vitamin D.

Click the icon to see an image of the sources of vitamin D.

Click the icon to see an image of the parathyroid glands.

Several studies on family members, including twins, have strongly suggested that genetic factors help determine bone density. Some examples include the following:

Of particular interest are genetic factors that affect vitamin D, a critical nutrient for calcium absorption in the body.
Many studies are looking at abnormalities in genes that may cause deficiencies in estrogen receptors, molecules that help estrogen work on cells. Estrogen is important in maintaining bone density in both men and women.

Corticosteroids. More than 30 million Americans have disorders that are commonly treated using corticosteroid drugs (also called glucocorticoids or steroids). Oral corticosteroids can reduce bone mass in both men and women. It is not clear whether inhaled steroids carry the same risks, but some studies indicate that they may cause bone loss when taken at higher doses for long periods of time. (Children on inhaled steroids may have temporary impaired growth, but they do not appear to be at risk for bone loss.)

Antidepressants. Selective serotonin reuptake inhibitors (SSRIs) -- a class of antidepressants that includes fluoxetine (Prozac), paroxetine (Paxil), and sertraline (Zoloft) -- may be associated with bone loss in both older men and women, according to two 2007 studies in the Archives of Internal Medicine. The researchers did not find an increased risk for bone loss with other types of antidepressants.

Diuretics. Diuretics, which are used to treat high blood pressure, have different effects on osteoporosis, depending on the type. Loop diuretics, such as furosemide (Lasix), increase the kidneys’ excretion of calcium, which can lead to thinning bones. Thiazide diuretics, on the other hand, protect against bone loss, but this protective effect ends after use is discontinued.

Contraceptives. Hormonal contraceptives that use progestin without estrogen (such as Depo-Provera injection or other progestin-based contraceptives), can cause loss of bone density. For this reason, the Food and Drug Administration (FDA) recommends that Depo-Provera injections should not be used for longer than 2 years. Some, but not all, studies suggest that combination estrogen-progestin oral contraceptives increase the risk for osteoporosis later in life. Women who take birth control pills should be sure to get adequate calcium and vitamin D from diet or supplements.

Other Medications. Anti-epileptic (anti-seizure) drugs increase the risk for bone loss (as does epilepsy itself). Other drugs that increase the risk for bone loss include the blood-thinning drug heparin, and hormonal drugs that suppress estrogen (such as gonadotropin-releasing hormone agonists). A 2006 study in the Journal of the American Medical Association suggested that long-term (greater than 1 year) use of proton-pump inhibitors (PPIs) may increase the risk for hip fractures. PPIs are used to treat gastroesophageal reflux disease (heartburn) and include omeprazole (Prilosec), lansoprazole (Prevacid), and esomeprazole (Nexium).

Predisposing Medical Conditions. Osteoporosis can be secondary to several other conditions, including alcoholism, diabetes, hyperthyroidism, epilepsy, chronic liver or kidney disease, celiac disease, scurvy, rheumatoid arthritis, leukemia, cirrhosis, gastrointestinal diseases, vitamin D deficiency, hypogonadism (impaired development of reproductive organs), lymphoma, hyperparathyroidism, and rare genetic disorders such as Marfan and Ehlers-Danlos syndrome.

Symptoms

Many people confuse osteoporosis with arthritis and believe they can wait for symptoms such as swelling and joint pain to occur before seeing a doctor. However, the mechanisms that cause arthritis are entirely different from those in osteoporosis. Osteoporosis usually becomes quite advanced before symptoms appear.

All too often, osteoporosis becomes apparent in dramatic fashion: a fracture of a vertebra (backbone), hip, forearm, or any bony site if sufficient bone mass is lost. These fractures frequently occur after apparently minor trauma, such as bending over, lifting, jumping, or falling from the standing position.

Pain, disfigurement, and debilitation are common in the latter stages of the disease. Early spinal compression fractures may go undetected for a long time, but after a large percentage of calcium has been lost, the vertebrae in the spine start to collapse, gradually causing a stooped posture called kyphosis, or a "dowager’s hump." Although this is usually painless, patients may lose as much as 6 inches in height.

Click the icon to see an image of osteoporosis.

Fractures

Bone density loss from osteoporosis is a major cause of disability and death in the elderly, mostly due to subsequent fractures. The lifetime risk of spinal fracture in women is about one in three, and that for hip fracture is one in six. Women at highest risk for fractures are those with low bone density plus a history of fractures, particularly nonviolent fractures.

Click the icon to see an animation about osteoporosis.

Each year, there are an estimated 500,000 spinal fractures, 300,000 hip fractures, 200,000 broken wrists and 300,000 fractures of other bones. About 80% of these fractures occur after relatively minor falls or accidents.

Between 25 - 60% of women older than age 60 develop spinal compression fractures. Studies on men with osteoporosis report that they have a 6% risk for hip fracture and between 16 - 25% risk for any fractures related to osteoporosis.

Click the icon to see an image of a compression fracture.

Click the icon to see an image of a hip fracture.

Unfortunately, studies continue to report inadequate treatment after a fracture. In a major 2003 study, for example, only 8.4% of women who had sustained fractures were tested for osteoporosis. Worse, less than half of these women received any treatment for osteoporosis. Overall, in the study fewer than 4% of men and half of women who had sustained fractures were evaluated and treated according to recommended guidelines. The older a woman was, the less likely she was to have adequate treatment.

Risk Factors for Fracture and Falling. The risk for fracture itself in people with low bone density is compounded by certain features. Having multiple risk factors for osteoporosis itself poses a higher risk for fractures. However, not all older women with osteoporosis develop fractures. There is some evidence that the body partially compensates after menopause by increasing bone strength, which can help offset the risk for fracture.

Falling, of course, is the primary risk factor for fracture. So, additional risk factors for fracture are those that increase the risk for falling. They include:

Having chronic medical problems (emphysema, heart disease, stroke, arthritis, and depression), with the risk increasing with multiple health problems. Such problems may account for 30% of falls in older women.
Taking multiple medications (especially tranquilizers and antidepressants).
Poor physical function, importantly slow gait and reduced muscle strength. Inactivity that results in weak thigh muscles and poor balance particularly puts any older person at risk for fracture and particularly those with low bone density.
Poor concentration or mental impairment.
Impaired vision.
Hazardous environment (such as the presence of throw rugs in the house).

Between 25 - 36% of women who experience a hip fracture die within a year afterward, and about a quarter of the patients require nursing home treatment. The mortality rates after major fractures may be even higher in older men than in older women. Mortality rates after hip fractures declined from the 1960s through the early 1980s, but they have since leveled off. Whether or not medical advances can improve mortality rates in the future, prevention of osteoporosis is extremely important.

Risk Factors

Gender. An estimated 10 million adults in the United States have osteoporosis and another 34 million have low bone mass that places them at risk for developing osteoporosis. A 2004 report from the Surgeon General's office estimates that by 2020, half of all Americans over age 50 could be at risk for this condition. Eighty percent of people with osteoporosis are women. Men start with higher bone density and lose calcium at a slower rate than women, which is why their risk is far lower. Nevertheless, after age 50, bone loss increases and, according to recent studies, more rapidly than previously thought.

Ethnicity. Although adults from all ethnic groups are susceptible to developing osteoporosis, Caucasian and Asian women and men face a comparatively greater risk. About 20% of non-Hispanic white and Asian women older than age 50 have osteoporosis, and over 50% are at risk due to low bone mass. Osteoporosis affects 10% of Hispanic women (49% at risk) and 5% of non-Hispanic black women (35% at risk). Body type can also be a factor. Osteoporosis is more common in women who have a small, thin body frame and bone structure.

Events associated with estrogen deficiencies are the primary risk factors for osteoporosis in women.

Natural and Surgical Causes of Estrogen Deficiency.

Menopause. Within 5 years after menopause, the risk for fracture increases dramatically. Fractures occurring during this period are more likely to occur in the wrist or spine than the hip, but their occurrence is a strong predictor of later severe osteoporosis and hip fracture.
Surgical removal of ovaries.
Missing periods for 3 months or longer.
Never giving birth.
Pregnancy and nursing do not increase the risk for osteoporosis even though during those times calcium is diverted from the mother to the baby. A factor believed to be associated with reduced bone density is elevated at a constant level during nursing, but as the baby is weaned, levels of the factor decline and bone formation is restored.

Female Athlete Triad. In athletes, excessive exercise plays a major role in many cases of anorexia (and, to a lesser degree, bulimia), which in turn increases the risk for low estrogen levels and bone loss. The term "female athlete triad" in fact, is now a common and serious disorder facing young female athletes and dancers and describes the combined presence of the following problems:

Osteoporosis
Amenorrhea (absence or irregular menstruation)
Eating disorders

Some specific risk factors in men include:

Hormonal deficiencies, including both testosterone and estrogen, which occur in older men (although much more slowly than in women). Estrogen deficiencies may also play a major role in osteoporosis in older men. It is unknown yet what normal estrogen levels are in men.
Medical conditions that can reduce testosterone levels, such as prostate cancer treatments, testicular surgery, and mumps.
Hypogonadism, which is a severe deficiency in the primary hormone that signals the process leading to the release of testosterone and other important reproductive hormones.

Of concern, are studies suggesting that men who have osteoporosis and suffer hip fractures are far less likely to be tested and treated for low bone density than are women. In one study, only 27% of men were treated for osteoporosis compared to 71% of women.

Dietary Factors. Diet plays an important role in preventing and speeding up bone loss in men and women. Calcium and vitamin D deficiencies, of course, are important factors in the risk for osteoporosis. Other dietary factors may also be harmful or protective for certain people.

Calcium requires adequate vitamin D in order to be absorbed by the body. In the United States, many food sources of calcium such as milk are fortified with vitamin D.

Click the icon to see an image of the sources of calcium.

Lack of Exercise. Lack of exercise can put thinner people at risk for osteoporosis.

Being Underweight. Being underweight is a risk factor for osteoporosis in men as well as women. (Shortness, thinness, and narrow hips all increase the risk for fracture in people with low bone density.)

Lack of Sunlight. The photochemical effect of sunlight on the skin is a primary source for vitamin D. Bone formation peaks in the summer and bone breakdown increases in the winter. People who avoid sun exposure to prevent skin cancer may be at risk for vitamin D deficiency, particularly it they are elderly.

Click the icon to see an image of the sources of vitamin D.

Smoking. Women who smoke, particularly after menopause, have a significantly greater chance of spine and hip fractures than those who don’t smoke. Men who smoke also have lower bone density.

Diabetes. Diabetes changes bone quality and density and increases the risk for osteoporosis, but the effects differ depending on type:

Type 1 diabetes is associated with a slightly reduced bone density, putting patients at risk for osteoporosis and possibly fracture.
Type 2 diabetes, on the other hand, is associated with an increased bone density. In such cases, the bone quality itself may be impaired, since people with type 2 diabetes are still at higher risk for fractures.

Older patients with any diabetes type are at high risk for falling, which compounds the risk for fracture.

The maximum density that bones achieved during the growing years is a major factor in whether a person goes on to develop osteoporosis. Persons, usually women, who never develop peak bone mass in early life are at high risk for osteoporosis later on. Children at risk for low peak bone mass include children who are:

Born prematurely
Have anorexia nervosa (more common in girls)
Young, highly competitive athletes
Take oral corticosteroid drugs (inhaled steroids, which are common in asthma treatments, appear to pose a very low risk or none at all)
Have certain medical conditions (cystic fibrosis, epilepsy, inflammatory bowel disease, and celiac disease)
Have delayed puberty

Although to a large extent genetics predict bone health, exercise and good nutrition during the first three decades of life (when peak bone mass is reached) are still excellent safeguards against osteoporosis (and countless other health problems).

Diagnosis

About 20 - 30% of Caucasian women in the U.S. can expect to be affected by osteoporosis, including having a spinal fracture, after age 60. Hispanic, Asian, and Native American women have an even higher risk. Nearly all of them are unaware of the condition and so fail to seek a diagnosis. Even worse, studies continue to report inadequate evaluation for osteoporosis even after a fracture.

Evidence suggests that screening for osteoporosis can help prevent fractures. Expert groups now recommend bone density screening for the following people:

All women over age 65.
Any postmenopausal women under 65 years with risk factors for osteoporosis (being thin, being a smoker, having a family history of osteoporosis, corticosteroids use, or any serious high-risk condition, such as hyperthyroidism or early menopause).
Any older men or women who suffer a fracture. (Unfortunately, studies suggest that only a minority of these patients are evaluated and treated for osteoporosis. Men are especially less likely to be tested.)

Whether perimenopausal women should be screened is unclear. (Perimenopause is the period that extends a few years before and after menopause, usually ages 50 - 59.) Some experts believe that women as young as 21 who have strong risk factors for osteoporosis (such as anorexia or absence of menstruation due to over-exercising) should consider being tested. It is also important that older women continue to get bone density tests. A 2006 study found that only 10% of women over age 75 receive bone density screenings, even though they are the age group most likely to have hip fractures.

Bone Densitometry. The standard technique for determining bone density is a form of bone densitometry called dual-energy x-ray absorptiometry (DEXA). DEXA is simple and painless and takes 2 - 4 minutes. The machine measures bone density by detecting the extent to which bones absorb photons that are generated by very low-level x-rays. (Photons are atomic particles with no charge.) Measurements of bone mineral density are generally given as the average concentrations of calcium in areas that are scanned.

A bone density scan measures the density of bone in a person. The lower the density of a bone the higher the risk of fractures. A bone scan, along with a patient's medical history, is a useful aid in evaluating the probability of a fracture and whether any preventative treatment is needed. A bone density scan has the advantage of being painless and exposing the patient to only a small amount of radiation.

Bone mineral density is usually measured at the hip rather than the spine or wrist, which appears to be the most predictive of hip fracture. (Hip fractures are the most dangerous fractures, particularly in women older than sixty.) The bone density in the spine may also be measured. (Spinal bone density in older people however may be misleading. Bone density in this group may increase because of compression on the spinal bones from arthritic changes in the spine. Therefore, bone density measurements may be normal or even high, but the patient may actually be at risk for fracture.)

Click the icon to see an image of a hip fracture.

Ultrasound. Ultrasound techniques measure bone density in the heels, fingers, and leg bones. In early studies, advanced ultrasound techniques, such as quantitative ultrasound (QUS), are promising for improving accuracy in predicting fractures when used with DEXA. Ultrasound itself is less expensive than DEXA and uses no radiation. Ultrasound bone tests are sometimes given at health fairs or other non-medical settings. It should be noted that these results typically vary widely from measurements of the hipbone and are not reliable when used alone.

Quantitative Computed Tomography. Quantitative computed tomography (QCT) scans, a form of CT scans, can provide highly detailed information about spinal density. Radiation doses from this technique are higher than the others. Whether QCT predicts fracture risk accurately is, however, unknown.

Osteoporosis is diagnosed when bone density has decreased to the point where fractures will happen with mild stress, the so-called fracture threshold. This is determined by measuring bone density and comparing the results with the norm. However, low scores on bone density are not very accurate in determining fracture risk without consideration of other risk factors for fracture.

In general, doctors take the following steps to determine osteoporosis:

Bone mineral density ) is measured, typically in the hipbone, using bone densitometry.
Measurements of bone mineral density are given as mg/cm.² This is the average concentration of bone mineral in the areas that are being scanned. In general, bone is normal if results are greater than 833 mg/cm.² Low bone density (osteopenia) is between 833 and 648 mg/cm.² Osteoporosis is diagnosed with results below 648 mg/cm.²

These measurements still do not always indicate the true risk for fracture. The doctor also assesses risk factors and other considerations. The next step is to compare the patient's bone mineral density to normal bone density, which is defined as the average bone mineral density in the hipbones of premenopausal Caucasian women. (This group is used as the basis for the norm because of their high risk and greater proportion in the American population.)

The health professional then uses this comparison to determine her standard deviation (SD) from this norm. Standard deviation results are given as Z and T scores:

A T score gives the standard deviation of the patient in relationship to the norm in young adults. Doctors often use the T-score and other risk factors to determine the risk for fracture.
A Z score gives the standard deviation of the patient in relationship to the norm in her own age group. Z scores may be used to monitor the effects of treatments in women who have been diagnosed with osteoporosis.

For example, the lifetime risks for a younger woman with a specific T-score would be higher than the same scores in an older woman because the younger woman would have a longer time to lose bone density. In general, the T scores in a 55-year-old woman suggest the following degrees of risk for hip fracture.

One standard deviation or less below the norm indicates normal bone mineral density. (This carries a lifetime chance for a hip fracture of up to about 20%, depending on age and other risk factors.)
Between 1 and 2.5 standard deviation s below normal defines osteopenia, which is low bone density. This carries between a 20 - 50% lifetime risk for fracture.
More than 2.5 standard deviation s predicts osteoporosis and over a 60% chance for hip fracture. Additional risk factors increase the risk. They include low weight, smoking, risks for falling, and especially a history of previous fractures. For example, in women 65 years old with low bone density but no adverse factors, the risk for fracture is 4.3% in 1 year and 28.6% over 5 years. In similar women with a previous fracture, the probability of fracture at 1 year is 11% and at 5 years is 71.8%.

Not all older women with osteoporosis develop fractures. There is some evidence that the body partially compensates after menopause by increasing bone strength, which can help offset the risk for fracture. Techniques to measure bone strength may better identify women at higher or lower risk.

Note: Because the standards are based on Caucasian women, they do not necessarily apply to men, children, or to non-Caucasian women. For example, men have a lower risk for fracture at the same standard deviations as women. Researchers are attempting to establish risk guidelines for these groups as well.

Laboratory blood or urine tests for identifying certain markers of bone loss may prove to be useful in certain cases:

High levels of the chemicals deoxypyridinoline and C-telopeptide in the blood may indicate increased risk for hip fracture. These substances are produced when bone is broken down.
A urine test detecting a substance called N-telopeptide may indicate bone loss (although it is not associated with any risk for fracture).

Lifestyle Changes

Because osteoporosis affects such a considerable portion of the female population, total prevention may not be possible, particularly for high-risk groups. Once a woman goes through menopause and more rapid bone depletion occurs, the line between prevention and treatment blurs. Despite their lower risk for osteoporosis, men should also protect their bones with the same healthy lifestyle habits.

Exercise is very important for slowing the progression of osteoporosis. Although mild exercise does not protect bones, moderate exercise (more than 3 days a week for more than a total of 90 minutes a week) reduces the risk for osteoporosis and fracture in both older men and women. Everyone who is in good health should aim for more. Exercise should be regular and life-long. Before beginning any strenuous exercise program, older patients, those at risk or those who have serious medical conditions, should talk to their doctors.

Specific exercises may be better than others, depending on the age group:

Children should begin exercising before adolescence, since bone mass increases during puberty and reaches its peak between ages 20 and 30. Some evidence suggests that exercise may help develop bone mass in teenagers more effectively than high calcium intake. High-intensity exercises may be particularly bone-strengthening in young people. (Such regimes should not be confused with the athlete-triad -- intense competitive exercise, eating disorders, and menstrual irregularities -- that causes osteoporosis in young athletes.)
Weight-bearing exercise applies tension to muscle and bone and, in young people, encourages the body to compensate for the added stress, increasing bone density by as much as 2 - 8% a year. In premenopausal women these exercises are very protective. (Young men need high-intensity exercises to increase bone mass.) Careful weight training is also very beneficial for elderly people, especially women.
Regular brisk long walks improve bone density and mobility and may relieve osteoarthritic pain. High-impact exercises can be very bone-protective in young and middle-aged adults who have no precluding medical or physical conditions. Most older individuals should avoid high-impact aerobic exercises (step aerobics), which increase the risk for osteoporotic fractures. (Older people, particularly women who engage in jumping exercises should do so under supervision.) Although low-impact aerobic exercises such as swimming and bicycling do not increase bone density, they are excellent for cardiovascular fitness and should be part of a regular regimen.
Exercises specifically targeted to strengthen the back help prevent fractures later on in life and can be beneficial in improving posture and reducing kyphosis (hunchback), even in people with existing severe conditions.
Low-impact exercises that improve concentration, balance, and strength, particularly yoga and tai chi, have been found to decrease the risk of falling. In one study, tai chi reduced the risk of falling by almost half.

Exercise plays an important role in the retention of bone density in the aging person. Studies show that exercises requiring muscles to pull on bones cause the bones to retain and possibly gain density.

Click the icon to see an image of osteoporosis.

In 2007, the Food and Drug Administration (FDA) proposed a new health claim for foods and dietary supplements that contain calcium and vitamin D. The FDA’s recommendation will allow manufacturers of these products to state that the combination of calcium and vitamin D can reduce the risk of osteoporosis. Also in 2007, the National Osteoporosis Foundation (NOF) updated its recommendations for getting enough calcium and vitamin D3. The NOF now recommends 1,200 mg of calcium/day and 800 - 1,200 I.U. of vitamin D3/day for adults age 50 and older. (For strong bones, people need enough of both calcium and vitamin D.)

For years, doctors have recommended that women take supplements of calcium plus vitamin D to help maintain bone density and reduce the risk for fractures. Many studies, including a 2007 review in the Lancet, show that a combination of calcium and vitamin D can help prevent osteoporosis. However, a 2006 New England Journal of Medicine study raised some questions about this approach. In the Women’s Health Initiative study, women were randomly assigned to receive either 1,000 mg of calcium carbonate plus 400 IU of vitamin D a day or placebo. The results indicated that daily calcium and vitamin D supplements:

Improve slightly (by 1%) hip bone density
Prevent hip fracture, but only for women who consistently take the supplements. (Another 2006 study supported this finding.)
Do not prevent spine or other types of fractures
Produce a slight increase in the risk of kidney stones

The medical community has differing views on how to interpret these findings. Some doctors recommend that women over age 60 should still consider taking calcium and vitamin D for bone health. Other doctors feel that due to the risks of kidney stones, supplements are beneficial only for women (especially those over age 70) who do not get enough calcium in their diets. Ask your doctor whether or not you should take calcium supplements.

Appropriate Daily Doses. Recommended daily amounts of calcium depend on age and risk factors:

In young people, children ages 3 - 8 should take 800 mg of calcium per day, while children and adolescents ages 9 - 17 need 1,300 mg per day. Teenage girls who do not have enough calcium in their diets should consider taking supplements, which can help build bone density during these critical years.
The standard recommended dose for people over age 50 is about 1,200 mg per day, but actual dosage may be higher or lower depending on risk factors. Even doses of 1,000 mg may help preserve bone in many postmenopausal women without osteoporosis, including during winter months (when bone loss is greatest). In women who have already experienced osteoporosis-related fractures, however, 1,000 mg daily may not add any protective benefits without bone-building medication.
Some experts suggest that all pregnant women, adolescents, and those on corticosteroids take 1,000 - 1,300 mg of calcium every day.
Breast-feeding women should have 2,000 mg per day.

Forms of Calcium Supplements. There are several different kinds of calcium supplements, such as calcium carbonate (Caltrate, Os-Cal, Tums), calcium citrate (Citracal), calcium gluconate, and calcium lactate. Although each kind provides calcium, they all have different calcium concentrations, absorption capabilities, and other actions. Their value in preserving bones depends on many different factors:

Calcium Concentrations. Forty percent of calcium carbonate is actually calcium, whereas calcium citrate is 24% calcium, and calcium gluconate is only 9% calcium.
Calcium Absorption Capabilities. The calcium must also be absorbed from the stomach into the bloodstream. Calcium citrate is better absorbed than many other calcium compounds. It was reported to be the first calcium supplement to preserve bone density after menopause. (Calcium citrate also increases iron absorption. Milk and other calcium compounds tend to reduce iron absorption.) One simple method for testing the absorbency of a particular brand of calcium tablet is to place it in a glass of white vinegar at full strength and check to be sure that it breaks up within 30 minutes. Taking large amounts of antacids can impair calcium absorption. People should take calcium supplements after meals.

Side Effects. Calcium supplements, even at normal doses of about 1,000 mg a day, can increase the risk for kidney stones. People should be careful not to exceed the upper limit of 2,500 mg per day. (Because many commercial foods are now fortified with calcium, this upper limit may be easier to reach than people think.) Calcium may boost the effects of drugs used to treat osteoporosis.

Click the icon to see an image of kidney stones.

Although not a specific side effect of calcium, there has been much public concern about reports of a small amount of lead in calcium supplements. Although exposure to high levels of lead can cause health problems, the amount in such supplements is very small and may pose little or no hazard.

Vitamin D. Vitamin D helps the stomach and the gastrointestinal tract absorb calcium. It also is the essential companion to calcium in maintaining strong bones. Moreover, vitamin D protects against osteoporosis only in combination with calcium.

Click the icon to see an image of the benefits of vitamin D.

Vitamin D is made in the skin using energy from the ultraviolet rays in sunlight. People also can get it from dietary supplements.

As a person ages, vitamin D levels decline. They also fall during winter months and when people have inadequate sunlight. Pollution may also contribute to less sunlight and declining vitamin D levels.

Click the icon to see an image of the sources of vitamin D.

Most current adult guidelines recommend:

400 IU (10 mcg) for people aged 50 - 60.
600 IU (15 mcg) for those over age 70 who do not have sufficient exposure to sunlight. (Evidence suggests that higher doses of vitamin D -- up to 1,000 IU per day -- may help prevent fractures in people with osteoporosis.)

There are various recommendations for daily vitamin D intake. In 2007, the National Osteoporosis Foundation updated its guidelines to recommend 400 - 800 IU of vitamin D3 for adults younger than age 50, and 800 - 1,000 IU of vitamin D3 for adults age 50 and older. Vitamin D3, also called cholecalciferol, is the form of vitamin D that is best for bone health. In addition to supplements, food sources for vitamin D3 include fortified milk, egg yolks, saltwater fish, and liver.

In 2007, the U.S. National Institute of Health’s Office of Dietary Supplements released a report regarding vitamin D and bone health. Researchers were not able to definitely separate the effect of vitamin D from that of calcium, as most clinical trials evaluate the combination of these supplements. The report did indicate that a combination of daily vitamin D3 (700 - 800 IU) and calcium (500 - 1,200 mg) decreases the risks of falls, fractures, and bone loss in elderly people (ages 62 - 85 years).

Sufficient sunlight exposure and drinking milk fortified with vitamin D supply most people’s normal needs for vitamin D. One cup of whole milk provides about 100 IU of vitamin D.

Vitamin D is toxic in doses above 2,000 IU a day. No one should exceed the recommended daily intake of vitamin D except under the direction of a doctor.

Many people could become deficient in vitamin D as they avoid sunlight to prevent skin cancers and instead increase their intake of milk products, such as yogurt and skim milk, which may have little vitamin D. Such individuals may need to take supplements. People with darker skin have a higher risk for vitamin D deficiency than those with lighter skin.

Vitamin D derivatives are being investigated for treating osteoporosis. Calcitriol (Calcijex, Rocaltrol), for example, is a prescription-form of vitamin D that can increase bone mass and decrease the rate of spinal fractures. However, calcitriol increases the risk for high blood calcium levels (hypercalcemia) and requires frequent monitoring.

Vitamin K. Vitamin K has properties that protect bone and prevent fracture. Because intestinal bacteria produce vitamin K, and the vitamin is found in leafy vegetables, deficiencies are rare. Some evidence suggests, however, that people may not be consuming enough of this nutrient. Vitamin K affects blood clotting, and taking supplements is not recommended without first talking to a doctor. Vitamin K2 (menatetrenone), a form of vitamin K, may help prevent fractures in people with osteoporosis.

Click the icon to see an image of the benefits of vitamin K.

Click the icon to see an image of the sources of vitamin K.

Vitamin B12. Studies suggest that people need the right amounts of vitamin B12 and folic acid to maintain their bone mineral density.

Vitamin A. High amounts of dietary vitamin A reduce bone density and may even increase the risk for fracture in postmenopausal women. (A form of vitamin A, retinoic acid, has been found to stimulate bone breakdown.)

The DASH Diet and Low Sodium. Perhaps a good general approach for people at risk for osteoporosis (or almost any adult) is the DASH diet plus sodium (salt) restriction. The DASH (Dietary Approaches to Stop Hypertension) diet is used to help people with hypertension maintain healthy blood pressures. A 2003 study also reported that it might help protect bones and improve cholesterol levels. This diet not only is rich in important nutrients and fiber but also includes foods that contain far more potassium, calcium, and magnesium, than are found in the average American diet. All of these minerals are important for bone protection. The dietary recommendations are as follows:

Avoid saturated fat (although include calcium-rich dairy products that are no- or low-fat). When choosing fats, select monounsaturated oils, such as olive or canola oils. These fats are also found in some fish. Although no one wants to be overweight, even a slight excess of fat helps protect bones. In one study, women who ate more fat in their diet were, on average, better able to absorb calcium than were women who had been put on a low-fat, high-fiber diet.
Choose whole grains over white flour or pasta products. Include nuts, seeds, or legumes (dried beans or peas) daily.
Choose fresh fruits and vegetables every day. Many of these foods are rich in potassium, magnesium, and other minerals that are important for bone (as well as heart) protection.
Choose protein preferably from fish, poultry, or soy products. Soy in combination with fiber-rich foods or supplements may have specific benefits. Oily fish may also be particularly beneficial. They contain omega-3 fatty acids, which have been associated with heart and nerve protection.

Salt Restriction. Reducing salt may protect both the heart and the bones. High sodium intake interferes with calcium retention. Note: Fast foods and commercial snacks are usually high in sodium and have been linked with weak bones.

Dairy Products and Calcium-Rich Foods. Although some studies have reported that dairy products benefit the bones, it is not entirely clear if high-calcium diets reduce the risk for fractures compared to adequate intake of vitamin D. Until more is known, people should be sure their diets have sufficient calcium. Dietary calcium is available from many good sources.

Milk and Dairy Products. The best source of calcium in the diet is from milk fortified with vitamin D. Four glasses of milk provide about 1,200 mg of calcium. (Skim milk and yogurt products, unfortunately, are often low in vitamin D, which is important for calcium absorption.) According to a 2003 study, girls who have low milk intake increase their risk for fracture in adulthood. One report even suggests that milk proteins actually slow bone break down. It is not clear, however, if drinking milk after menopause offers any significant bone protection.
Other Calcium-Rich Foods. Other calcium-rich foods include shrimp, canned salmon or sardines, black strap molasses, calcium-fortified tofu, and almonds. A number of commercial foods, including orange juice and some cereals, are now calcium fortified. Dark green vegetables (broccoli, kale, turnip greens) are rich in calcium but little of it is absorbed (kale is best).

Click the icon to see an image of milk and the facial bones.

Mineral-Rich Fruits and Vegetables.

Potassium. Potassium may be very important for strong bones and may help counteract negative effects of high-protein diets. Potassium-rich fruits include bananas, oranges, prunes, and cantaloupes, and vegetables that contain potassium include carrots, spinach, celery, alfalfa, mushrooms, lima beans, potatoes, avocados, and broccoli.
Magnesium. Some studies have observed that low levels of magnesium may contribute to thinning bones. Some studies suggest that magnesium supplements help suppress the cycle that leads to bone loss. Experts recommend 350 mg a day for supplements. However, excessive magnesium may be harmful in people with diabetes or kidney disease. Foods rich in magnesium include dairy products, spinach, potatoes, beets, nuts, sole, and halibut.
Other Minerals. Phosphorous, boron, and zinc have also been associated with bone protection.

Protein. Protein may be important for frail older people for improving muscle strength. Researchers, meanwhile, have associated both low and high protein intake with bone loss. Protein deficiencies appear to trigger hormonal changes that increase bone breakdown. On the other hand, high protein intake increases urinary calcium loss, which can impair bone density in people with low-calcium diets. High-protein diets, however, do not appear to cause bone loss if calcium intake is also high. The bottom line is to eat enough protein but to balance it with plenty of calcium-rich, and other mineral-rich, foods.

The protein source (meat, soy, or fish) may have some effect on bone density, although the effects are not clear. Studies are mixed on whether protein from meat has a positive or negative effect on bone loss. In any case, the best sources of protein for bone protection may be from oily fish or soy.

Choosing protein from fish (especially oily fish such as sardines, salmon, mackerel, fresh tuna, and herring) is a good option. Oily fish are high in vitamin D, which is bone protective. Such fish are also heart protective. Wild salmon has a much higher vitamin D content than farmed salmon. American brands of canned tuna, meanwhile, generally do not contain significant amounts of vitamin D.
Soy may have some modest protection against bone loss. Soy is high in estrogen-like plant chemicals called isoflavones, which may improve bone health in older women. In particular, the isoflavone genistein is being studied for its effects on bone health. A small 2007 study indicated that genistein supplements, when taken with vitamin D and calcium, may help improve bone density in postmenopausal women with thinning bones. (However, other studies indicate that soy has no effect on bone density in healthy premenopausal women.) Soy food products that also contain calcium, such as tofu, may be particularly beneficial. In such cases, 3 ounces of tofu supply 60% of daily calcium requirements.

Alcohol. Alcohol has different effects on bones depending on how much is consumed. One study found that women older than age 65 who drank one to two drinks (1 - 2 oz) of alcohol weekly had higher bone density than non-drinkers. Alcohol in moderate amounts may reduce parathyroid hormone and increase estrogen levels. Excessive drinking, however, has been associated with brittle bones.

Cola, Coffee, Tea and Caffeine. One study suggested that drinking tea regularly may help protect bones. Nevertheless, there has been some concern that caffeine consumption, particularly from coffee, may increase calcium levels in urine and reduce levels in the body. In one trial, consumption of lots of coffee (9 or more cups per day) was associated with an increased risk of hip fractures in women, but not in men. However, not all studies support a risk. Some evidence suggests that caffeine may pose a danger for bone loss only in elderly thin women -- but not in those who have normal or high weight. Drinking carbonated beverages, particularly cola, may increase the risk for bone fractures in people with low bone density.

Everyone who smokes should quit. The risk for osteoporosis from smoking appears to diminish after quitting.

An important component in reducing the risk for fractures is preventing falls. Risk factors for falling include:

Slow walking
Inability to walk in a straight line
Certain medications (such as tranquilizers and sleeping pills)
Low blood pressure when rising in the morning
Poor vision

Recommendations for preventing falls or fractures from falls in elderly people include:

Exercise to maintain strength and balance if there are no conflicting medical conditions. In one study of older people, this was the single best intervention for preventing falls.
Do not use loose rugs on the floors.
Move any obstructions to walking, such as loose cords or very low pieces of furniture, away from traveled areas.
Rooms should be well lit.
Have regular eye checkups.
Try wearing hip pads. Hip pads are specially designed to protect hipbones against falls and are worn under clothing. Evidence on their protection against fractures is weak, however, particularly since compliance is poor. Nevertheless, newer hip pads that are thinner and made with newer materials may be helpful and more appealing.
Wear thinner, hard-soled shoes. Studies indicate these shoes are just as comfortable as the popular resilient-soled footwear, but they may be difficult to find. Soft-soled high-resilient so-called athletic footwear may contribute to impaired balance and dangerous falls, in part, because these cushioned shoes offer less stability.

Medications

Many drugs are available to treat osteoporosis. Unfortunately, studies continue to report that doctors fail to evaluate and adequately treat both men and women for this condition, even after a fracture. According to one study of women over age 60, fewer than 2% were evaluated for osteoporosis or spinal fracture by their doctors. Among those who were diagnosed, only 36% received appropriate medication. Among adults who had sustained fractures, less than 5% of men and fewer than half of women were evaluated and treated according to recommended guidelines, indicated two other studies. In one of the studies, only 24% of women received treatment for osteoporosis after a fracture. In both studies, the older a woman was, the less likely she was to have adequate evaluation or treatment.

Drugs Used to Treat Osteoporosis. Two types of drugs are used to treat osteoporosis:

Antiresorptive Drugs. Antiresorptives include bisphosphonates, hormone replacement therapy, selective estrogen-receptor modulators (SERMs), and calcitonin. Bisphosphonates are the standard drugs used for osteoporosis. These drugs block resorption (preventing bone break down), which slows the rate of bone remodeling, but they cannot rebuild bone. Because resorption and reformation occur naturally as a continuous process, blocking resorption may eventually also reduce bone formation.
Anabolic, or Bone-Forming, Drugs. Drugs that rebuild bone are known as anabolics. The primary anabolic drug is low-dose parathyroid hormone (PTH), which is administered through injections. This medicine is proving to be very effective in restoring bone and preventing fractions. PTH is still relatively new, and long-term effects are still unknown. Fluoride is another bone-building drug, but it has limitations and is not commonly used.

Both types of drugs are effective in preventing bone loss and fractures, although they vary in their effectiveness and safety.

Bisphosphonates are antiresorptive drugs. They are the primary drugs for preventing and treating osteoporosis. They can help reduce the risk of both spinal and hip fractures, including among patients with prior bone breaks.

Studies indicate that these drugs are effective and safe for at least 10 years. Eventually, however, bone loss continues with bisphosphonates. This may be due to the fact that bone breakdown is one of two phases in a continuous process of rebuilding bone. Over time, just blocking resorption will interrupt this process and impair the second half of the process -- bone formation. Some researchers think that this problem may be overcome by building bone for a couple of years with parathyroid hormone (PTH), then following this treatment with bisphosphonates to prevent the breakdown of bone. (Administering the two drugs simultaneously is not effective because bisphosphonates interfere with the way PTH works.)

A 2006 study of the bisphosphonate alendronate (Fosamax), the most widely used osteoporosis drug, indicated that women at low risk for fracture may be able to stop using the drug after 5 years without increasing their fracture risk for another 5 years. However, the Journal of the American Medical Association study also suggested that it is safer for women at high risk for spine fractures to keep taking alendronate on a continuous basis.

Candidates. National Osteoporosis Foundation guidelines recommend that the following people should take or consider bisphosphonates:

Women with a below-normal bone density of 2.5 standard deviation or greater and no history of fractures
Women with below-normal bone density 1 standard deviation or more and a history of fractures

Brands. Bisphosphonates are available in different forms:

Oral bisphosphonates. These pills include alendronate (Fosamax), risedronate (Actonel), and ibandronate (Boniva). Alendronate and risedronate are taken once a week. In 2005, ibandronate was approved as the first once-monthly pill. Risedronate is also available in a pill that contains calcium. Risedronate and alendronate are approved for both men and women.
Injectable bisphosphonates. In 2007, zoledronic acid (Reclast) was approved as the first once-yearly injection treatment for osteoporosis. The injectable form of ibandronate (Boniva), approved in 2006, requires injections 4 times a year. Injectable bisphosphonates are an alternative for patients who may have difficulty swallowing pills or sitting upright after oral bisphosphonate treatment.

Side Effects. The most distressing side effects of bisphosphonates are gastrointestinal problems, particularly stomach cramps and heartburn. These symptoms are very common and occur in nearly half of all patients. Other side effects may include irritation of the esophagus (the tube that connects the mouth to the stomach) and ulcers in the esophagus or stomach. Some patients may experience muscle and joint pain. To avoid stomach problems, doctors recommend:

Take the pill on an empty stomach in the morning with 6 - 8 ounces of water (not juice or carbonated or mineral water).
After taking the pill, remain in an upright position. Do not eat or drink for at least 30 - 60 minutes. (Check your drug’s dosing instructions for exact time.)
If you develop chest pain, heartburn, or difficulty swallowing, stop taking the drug and see your doctor.

Osteonecrosis (bone death) of the jaw is a rare side effect that has occurred mainly in patients who received intravenous bisphosphonates for cancer treatment (not osteoporosis). Many of these patients had major dental procedures before developing osteonecrosis. However, this bone decay condition has also been reported in some patients who have taken bisphosphonates by mouth (mainly alendronate). Symptoms may include jaw pain or swelling, gum infections, and poor healing of the gums. Talk to your doctor or dentist if you experience any jaw or gum discomfort while taking a bisphosphonate drug.

Raloxifene (Evista) belongs to a class of drugs called selective estrogen-receptor modulators (SERMs). These drugs are similar, but not identical, to estrogen. Raloxifene provides the bone benefits of estrogen without increasing the risks for estrogen-related breast and uterine cancers. Raloxifene was approved in 1997 to prevent osteoporosis in postmenopausal women, and in 1999 for the treatment of osteoporosis in postmenopausal women. In 2007, the Food and Drug Administration approved raloxifene for prevention of breast cancer in postmenopausal women with osteoporosis, as well as postmenopausal women at high risk for invasive breast cancer.

While there are many SERM drugs, raloxifene is the only one approved for both treatment and prevention of osteoporosis. Only postmenopausal women who have or are at risk for osteoporosis should take this drug. Studies indicate that raloxifene can stop the thinning of bone and help build better quality and stronger bone.

A thrombus is a blood clot that forms in a vessel and remains there. An embolism is a clot that travels from the site where it formed to another location in the body. Thrombi or emboli can lodge in a blood vessel and block the flow of blood in that location, depriving tissues of normal blood flow and oxygen. This can result in damage, destruction (infarction), or even death of the tissues (necrosis) in that area.

Side Effects. Raloxifene increases the risk for blood clots in the veins. Because of this side effect, raloxifene also increases the risk for stroke (but not other types of heart disease). These side effects, though rare, are very serious. Women should not take this drug if they have a history of blood clots, or if they have certain risk factors for stroke and heart disease. More common mild side effects include hot flashes and leg cramps.

Produced by the thyroid gland, natural calcitonin regulates calcium levels by inhibiting the osteoclastic activity, the breakdown of bone. The drug version is derived from salmon and is available as a nasal spray (Miacalcin) and an injected form (Calcimar). Calcitonin is not used to prevent osteoporosis. It treats osteoporosis. It may be effective for spinal protection (but not hip) in both men and women. Calcitonin may be an alternative for patients who cannot take a bisphosphonate or SERM. It also appears to help relieve bone pain associated with established osteoporosis and fracture.

Side Effects. Side effects include headache, dizziness, anorexia, diarrhea, skin rashes, and edema (swelling). The most common adverse effect experienced with the injection is nausea, with or without vomiting. This occurs less often with the nasal spray. The nasal spray may cause nosebleeds, sinusitis, and inflammation of the membranes in the nose. Also, many people who take calcitonin develop resistance or allergic reactions after long-term use.

Although high persistent levels of parathyroid hormone (PTH) can cause osteoporosis, daily injections of low and intermittent doses of this hormone actually stimulate bone production and increase bone mineral density. In clinical studies, teriparatide (Forteo), a drug made from selected amino acids found in parathyroid hormone, reduced the risk for spinal and non-spinal fractures by 50 - 65%. It may prove to be a very useful drug for men with osteoporosis. Unlike most treatments for osteoporosis, including bisphosphonates, the benefits may persist even after the injections have been stopped.

Although the treatment requires injections, researchers are investigating a nasal spray version of PTH. In addition to easing patient discomfort, there is some preliminary evidence that nasal-administered PTH may be better absorbed than injections. Side effects of PTH are generally mild and include nausea, dizziness, and leg cramps. No significant complications have been reported to date.

Early animal studies did report bone tumors in mice that were given parathyroid long-term. Such effects have not been observed in humans to date. However, people with Paget disease, (a disorder in which bone thickens but also, oddly, weakens), should not take parathyroid hormone, since they are at higher than normal risk for bone tumors.

Hormone replacement therapy (HRT) is sometimes used to prevent osteoporosis. A Women’s Health Initiative (WHI) study found that women who received estrogen, or estrogen plus progestin, therapy had fewer fractures than women who received placebo.

However, WHI studies have also shown that estrogen increases the risk for breast cancer, blood clots, strokes, and heart attacks. For this reason, women need to balance the benefits that HRT has on bone-loss protection, with the risks it carries for other serious health conditions. The Food and Drug Administration recommends that women first try other medications for prevention of osteoporosis.

HRT is available in many different forms, including pills and skin patches. [See In-Depth Report #40: Menopause.]

New SERMs. Bazedoxifene (Viviant) is a new selective estrogen receptor modulator (SERM) that is in phase III clinical trials. In research presented at the 2007 annual meeting of the American Society for Bone and Mineral Research (ASBMR), bazedoxifene reduced new cases of non-spine fracture by 52% compared to placebo.
Biologic Drugs. Denosumab is a humanized monoclonal antibody injectable drug currently in phase III studies. It targets the RANK ligand, a protein involved with cells that break down bone (osteoclasts). Results presented at the 2007 ASBMR meeting indicated that denosumab may help increase bone mineral density by as much as 10.6%. Odanacatib is another biologic drug showing promise in phase IIB trials. Odanacatib inhibits cathepsin K, a protein that also plays a role in osteoclast activity.
Strontium. Strontium, a chemical element found in bone, may help increase bone formation and decrease bone resorption. NB S101 is a strontium drug currently in phase II trials.

Treatment

Nonsurgical treatments for fractures include braces, plaster cases, and manipulation of the fracture. Such approaches have not been well studied to determine an optimal method, and patients should discuss all options with their doctors.

Reconstructive surgery is usually used for hip fractures and should be performed within 48 hours, assuming the patient has no other complicating medical conditions. After surgery, the patient should be mobilized within the first day. In one study, protein supplements helped people with hip fractures recover more quickly and reduced bone loss.

Percutaneous vertebroplasty and kyphoplasty are surgical procedures used to lessen pain. Research to date suggests that they are safe and provide pain relief for many patients. In some cases they may increase height. There have been few controlled trials, however, and more research is needed to determine long-term effects.

Percutaneous Vertebroplasty. Percutaneous vertebroplasty involves the injection of a cement-like bone substitute into damaged vertebrae. It is proving useful for stabilizing the spine and relieving pain in patients with spinal compression fractures due to osteoporosis or cancer. Success rates of over 90% have been reported. Serious complications occur in fewer than 1% of cases.

Kyphoplasty. Kyphoplasty is a variant of percutaneous vertebroplasty that may help prevent kyphosis (hunchback) in patients whose spines have collapsed. The procedure inserts a balloon into the fractured vertebrae. As the balloon inflates, the spine is moved upward, to its original location. The balloon is then removed, and the bone and the core of the newly-erect vertebrae are filled with cement. In one 2003 study, short-term symptom relief improved by 70% and was immediate. Long-term effectiveness is not yet known.

Resources

www.nof.org -- National Osteoporosis Foundation
www.niams.nih.gov/Health_Info/Bone -- National Institutes of Health, Osteoporosis and Related Bone Diseases
www.menopause.org -- North American Menopause Society
www.asbmr.org -- American Society for Bone and Mineral Research
www.niams.nih.gov -- National Institute of Arthritis and Musculoskeletal and Skin Diseases

References

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Black DM, Delmas PD, Eastell R, Reid IR, Boonen S, Cauley JA, et al. Once-yearly zoledronic acid for treatment of postmenopausal osteoporosis. N Engl J Med. 2007 May 3;356(18):1809-22.

Black DM, Schwartz AV, Ensrud KE, Cauley JA, Levis S, Quandt SA, et al. Effects of continuing or stopping alendronate after 5 years of treatment: the Fracture Intervention Trial Long-term Extension (FLEX): a randomized trial. JAMA. 2006 Dec 27;296(24):2927-38.

Diem SJ, Blackwell TL, Stone KL, Yaffe K, Haney EM, Bliziotes MM, et al. Use of antidepressants and rates of hip bone loss in older women: the study of osteoporotic fractures. Arch Intern Med. 2007 Jun 25;167(12):1240-5.

Haney EM, Chan BK, Diem SJ, Ensrud KE, Cauley JA, Barrett-Connor E, et al. Association of low bone mineral density with selective serotonin reuptake inhibitor use by older men. Arch Intern Med. 2007 Jun 25;167(12):1246-51.

Marini H, Minutoli L, Polito F, Bitto A, Altavilla D, Atteritano M, et al. Effects of the phytoestrogen genistein on bone metabolism in osteopenic postmenopausal women: a randomized trial. Ann Intern Med. 2007 Jun 19;146(12):839-47.

Tang BM, Eslick GD, Nowson C, Smith C, Bensoussan A. Use of calcium or calcium in combination with vitamin D supplementation to prevent fractures and bone loss in people aged 50 years and older: a meta-analysis. Lancet. 2007 Aug 25;370(9588):657-66.

Yang YX, Lewis JD, Epstein S, Metz DC. Long-term proton pump inhibitor therapy and risk of hip fracture. JAMA. 2006 Dec 27;296(24):2947-53.

Review Date:
11/1/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Kidney stones

FitSugar — Wed, 08 Oct 2008 17:35:35 -0700

In This Report

Highlights
Introduction
Causes
Risk Factors
Symptoms
Diagnosis
Treatment
Medications
Other Treatments
Complications
Prevention
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

New Research:

Patients who have the most common type of gastric bypass surgery, the Roux-en-Y, are at increased risk for kidney stones, beginning 6 months after surgery, according to a study published in 2006.

Causes of Kidney Stones:

Calcium stones form when there is an imbalance in the urine substances that promote and block the formation of stones. Often, the cause of this imbalance is unknown.
Having acidic urine or too much uric acid in the body leads to the formation of uric acid stones.
Struvite stones are almost always caused by urinary tract infections due to bacteria that produce certain enzymes.
Other stones, including cystine and xanthine stones, are usually due to genetic abnormalities.

Treatments:

In about 85% of patients, the kidney stones are small enough that they pass through normal urination, usually within 2 - 3 days.
Certain medications can prevent recurrence of stones in people who are at high risk.
Extracorporeal shock wave lithotripsy (ESWL) is a technique that uses sound waves (ultrasound) to break up simple stones in the kidney or upper urinary tract. The shock waves are delivered from outside the body.
Surgery may be necessary if the stone or stones are too big to pass, and cannot be broken down through ESWL.
A change of diet and increased drinking of fluids, especially water, will help prevent a recurrence.

Introduction

Kidney stones are hard, solid rocks that form in the urinary tract. In many cases, the stones are very small and can pass out of the body without any problems. However, if a stone (even a small one) blocks the flow of urine, excruciating pain may result, and prompt medical treatment may be needed.

The process of urination begins in the kidneys. The kidneys filter out fluids and waste from the body, producing urine. The two kidneys are located deep behind the abdominal organs, below the ribs and toward the middle of the back.

Each kidney contains over a million nephrons. These are the tiny filtration units of the kidney.
Each nephron is composed of a tiny group of blood vessels (a glomerulus) enclosed in a funnel-like structure called Bowman's capsule.
Each glomerulus filters waste products, water, and salts out of the liquid part of the blood (plasma) that has entered the kidney.
About 1% of the plasma is converted into urine. The rest returns into the blood to prevent dehydration. Urine is primarily made of acids, urea, and creatinine (nitrogen compounds).
Urine passes from Bowman's capsule into tiny tubules, which lead to large collecting tubes in the center of the kidney. As the urine passes through this network, it becomes more concentrated.
Urine then flows from the kidney through thin tubes called ureters into the bladder.
The bladder's stretchy walls expand to store the incoming urine until it leaves the body through a tube called the urethra.

The kidneys are responsible for removing wastes from the body, regulating electrolyte balance and blood pressure, and stimulating red blood cell production.

Click the icon to see an image of the urinary tract.

Occasionally, various salts build up on the inside surfaces of the kidney and form crystals. Eventually these crystals become large enough to form stones in the kidney, a condition called nephrolithiasis. Kidney stones (renal calculi) may also form in the ureter or the bladder. Combinations of minerals and other chemicals, some derived from a person's diet, make up the salts in these stones.

Click the icon to see an image of the kidney stones.

Calcium Stones. About 70 - 90% of all kidney stones are made of calcium, usually combined with oxalate, or oxalic acid. A number of common vegetables, fruits, and grains contain oxalate.

About 6% of calcium stones are made of calcium phosphate (called brushite).

Uric Acid Stones. Uric acid is responsible for close to 10% of kidney stones. It is the breakdown product of purines, nitrogen compounds found in our bodies and in certain foods. The breakdown of purines to uric acid occurs in the liver, and from there uric acid enters the bloodstream, most of it passing into the kidneys. From the kidneys, uric acid leaves the body in the urine. Often, uric acid stones occur with calcium stones.

Struvite Stones. Struvite stones are made of magnesium ammonium phosphate. They are almost always associated with certain urinary tract infections. Worldwide, they make up to 30% of all kidney stones. In the United States, however, less than 15% of all stones are struvite. Most struvite stones occur in women. The rate of these stones may be declining in America, perhaps because of better control of urinary tract infections.

Cystine Stones. A build-up of the amino acid cystine, a building block of protein, causes 1% of kidney stones in adults and up to 8% of stones in children. The tendency to form these stones is inherited. Cystine stones are marked by rapid growth and recurrence, which, if not treated promptly, can eventually lead to kidney failure.

Xanthine Stones. Other kidney stones are composed of xanthine, a nitrogen compound. These stones are extremely uncommon and usually occur as a result of a rare genetic disorder.

Click the icon to see an animation about kidney stones.

Causes

The key process in the development of kidney stones is supersaturation.

The urine carries salts, including calcium oxalate, uric acid, cystine, or xanthine.
These salts can become extremely concentrated if there is not enough urine, or if unusually high amounts of crystal-forming salts are present.
When salt concentration levels reach the point at which they no longer dissolve, these salts form crystals.

Different factors may be involved in either reducing urine amount, or increasing the levels of the salts.

Deficiencies in Protective Factors. Normally, urine contains substances that may protect against stone formation, including:

Magnesium
Citrate
Pyrophosphate
Enzymes

These substances:

Allow salt in the urine to be at higher-than-normal concentrations without forming crystals
Prevent crystal formation
Coat the crystals and prevent them from sticking to the surface of kidney tubes

Not having enough of these protective substances can cause stones.

Changes in the Acidity of the Urine. Changes in the acid balance of the urine can affect stone formation.

Uric acid and cystine stones mainly form in acidic urine.
Calcium phosphate and struvite stones increase in alkaline urine.

Factors that Bind Crystals to the Kidney Tubules. Researchers are studying the cells lining the kidney tubules in order to understand how and why early crystals bind to the tubes long enough to form stones. Under investigation are elevated levels of substances that either cause crystals to stick to the tubes or deficiencies in those that prevent them from sticking.

In general, calcium stones form when there is an imbalance in the urine substances that promote and block the formation of stones. Often, the cause of calcium stones is not known, and the condition is then called idiopathic nephrolithiasis. Research suggests that nearly all stones result from problems in the breakdown and absorption of calcium and oxalate. Genetic factors may play a role in about half of these cases. A number of medical conditions and drugs can also affect digestion and intestinal absorption.

Excess Calcium in the Urine (Hypercalciuria). Hypercalciuria (too much calcium in the urine) is responsible for as much as 70% of calcium-containing stones. A number of conditions may produce hypercalciuria. Many are due to genetic factors, but most cases are idiopathic (due to unknown causes).

The following can lead to hypercalciuria and calcium stones:

Too much calcium absorption in the intestines: In most of these conditions, genetic factors lead to increased calcium absorption in the intestine. Researchers are investigating a possible defective gene that regulates calcitriol, a form of vitamin D, which, in excess levels, may increase intestinal absorption of calcium.
Excessive chloride: Chloride has a negative charge, and calcium has a positive one, so they balance each other in the body. Excess chloride may lead to excess calcium. A gene known as CLCN5, which regulates chloride in the urine, is defective in many patients with calcium stones.
Renal calcium leak: In this condition, the filtering processes in the kidney fail, causing an increase of calcium in the urine.
Excessive sodium: High urinary levels of sodium result in increased levels of calcium. Certain defects in the kidney tubules transport system, which cause imbalances in sodium and phosphate, can lead to high calcium levels in the urine. A diet high in salt can also produce this effect.

Excess Oxalate in the Urine (Hyperoxaluria). Oxalate is the most common stone-forming compound. Excessive oxalate in the urine (hyperoxaluria) is responsible for up to 60% of calcium stones and is a more common cause of stones than too much calcium in the urine.

Hyperoxaluria can be either primary or secondary.

Primary hyperoxaluria is an inherited disorder in which too much oxalate in the urine is the main problem.
Secondary hyperoxaluria results from specific conditions that cause high levels of urinary oxalate.

Secondary hyperoxaluria is usually caused by too much dietary oxalates (found in a number of common vegetables, fruits, and grains) or by problems in the body's breakdown of oxalates. Such defects may be due to various factors:

Severe vitamin B6 deficiencies (usually due to genetic disorders)
Deficiencies in Oxalobacter formigene, an intestinal bacteria that breaks down oxalate
Short bowel syndrome, a condition that makes the intestines unable to properly absorb fat and nutrients; calcium may bind to unabsorbed fat instead of oxalates, which causes a buildup of oxalate
Androgens (male hormones)

Female hormones (estrogens) actually lower the risk of hyperoxaluria. Estrogen may help prevent the formation of calcium oxalate stones by keeping urine alkaline, and raising protective citrate levels.

A study published in 2006 found that patients who undergo the most common gastric type of bypass surgery, the Roux-en-Y, were at increased risk for calcium oxalate kidney stones, beginning 6 months after surgery. The study found that patients who underwent the procedure developed hyperoxaluria, and the condition was common 12 months after surgery. The authors also noted an increased number of kidney stone incidents in this patient group.

Excessive Calcium in the Bloodstream (Hypercalcemia). Hypercalcemia generally occurs when bones break down and release too much calcium into the bloodstream. This is a process called resorption. It can occur from a number of different diseases and events:

Hyperparathyroidism: Overactive parathyroid glands cause about 5% of calcium stones. People with this disorder have at least a 20% chance of developing kidney stones. Women are more likely to have this disorder than men.
Immobilization: Lack of movement can lead to kidney stones.
Renal tubular acidosis: This disorder causes acidic and alkaline imbalance. Renal tubular acidosis not only increases calcium levels in the bloodstream but also reduces protective citrate levels.

Hyperuricosuria is a condition of high levels of uric acid in urine. It occurs in between 15 - 20% of people (mostly men) with calcium oxalate stones. Urate, the salt formed from uric acid, creates the center of a crystal (nidus), around which calcium oxalate crystals form and grow. Such stones tend to be severe and recurrent. They appear to be strongly related to a high intake of protein. (Hyperuricosuria also plays a major role in some uric acid stones.)

Low Urine Levels of Citrate (Hypocitraturia). Citrate is the main substance in the body that is responsible for removing excess calcium. It also blocks the process that turns calcium crystals into stones. Low levels of citrate in the urine (hypocitraturia) is a significant risk factor for calcium stones. In addition, hypocitraturia also increases the risk for uric acid stones. This condition most likely contributes to about a third of all kidney stones.

Many conditions can reduce citrate levels. Some causes include:

Renal tubular acidosis
Potassium or magnesium deficiency
Urinary tract infection
Kidney failure
Chronic diarrhea

Often, however, the cause of hypocitraturia-related stones is unknown.

Low Levels of Other Stone-Blocking Compounds. Several other compounds in the urine, including magnesium and pyrophosphate, also prevent the formation of calcium stones. If any of these compounds are lacking, stones may develop.

Nanobacteria Infection. Nanobacteria are tiny infectious organisms that can pass from the blood into urine. They coat themselves with mineral deposits that resemble the composition of kidney stones. Cells infected with these bacteria develop mineral deposits on the inside and outside. Researchers believe that nanobacteria may form the cores of the kidney stones in many people.

Human body tissues, certain foods, and certain alcoholic drinks contain substances called purines. Purine-containing foods include dried beans, peas, and liver. When the body breaks down purines, it produces uric acid. The presence of a certain level of uric acid in the body is normal.

The following conditions are usually seen in patients with uric acid stones:

Too much acid in the urine for a long period (the most important cause of uric acid stones)
Lower than normal amounts of urine produced.
Hyperuricosuria, a metabolic disorder that leads to high levels of uric acid in the urine

Note: Hyperuricosuria can also trigger calcium stones. Therefore, a combination of calcium and uric acid stones may be present in patients with hyperuricosuria.

A number of conditions and other factors may contribute to, or cause, uric acid stones:

Gout: Uric acid and other kidney stones develop in up to 25% of patients with primary gout, a painful form of arthritis that occurs when uric acid in the blood forms crystals in one or more joints.
Diabetes: New research has shown that people with type 2 diabetes have highly acidic urine that can lead to kidney stones, particularly uric acid stones. The findings were published in the May 2006 Journal of the American Society of Nephrology.
Insulin resistance: People with insulin resistance are at an increased risk for uric acid stones. The reason is unknown but may be related to the transport of certain salts through the kidneys. This transport changes in patients with insulin resistance.
Kidney abnormalities: Kidney problems that reduce the production of ammonia, particularly in people with diabetes or insulin resistance, may lead to uric acid stones.
Genetic factors: Genetic factors can increase a person's risk for uric acid stones.
Hypocitraturia: Hypocitraturia is a low amount of citrate in the urine.
Diet: Eating too much animal protein increases the risk of forming uric acid stones.

Other risk factors include:

Certain medications (chemotherapy drugs, diuretics, and salicylates)
Binge drinking
Not eating for long periods of time (fasting)
Lead poisoning
Blood cancers (leukemia, multiple myeloma, and lymphomas)
Some rare types of anemia (low levels of red blood cells in the blood)
Chronic diarrhea

Struvite stones are almost always caused by urinary tract infections due to bacteria that produce certain enzymes. These enzymes raise the concentration of ammonia in the urine. Ammonia makes up the crystals that form struvite stones. The stone-promoting bacteria are usually Proteus, but may also include Pseudomonas, Klebsiella, Providencia, Serratia, and staphylococci. Women are twice as likely to have struvite stones as men.

Other stones, including cystine and xanthine stones, are usually due to genetic abnormalities.

Causes of Cystine Stones. Cystine stones develop from genetic defects that cause abnormal transport of amino acids in the kidney and gastrointestinal system leading to a build-up of cystine, one of these amino acids. Researchers have identified two genes responsible for this condition: SLC3A1 and CLC7A9.

Causes of Xanthine Stones. In some cases, xanthine stones may develop in patients being treated with allopurinol for gout.

Risk Factors

Kidney stones are one of the most common disorders of the urinary tract. They are an ancient health problem. Evidence of kidney stones has been found in an Egyptian mummy estimated to be more than 7,000 years old.

An estimated 1.3 million Americans seek medical help for kidney stones each year. At this time, studies suggest kidney stones affect over 5% of Americans and that the rate has increased since the 1970s, perhaps because of increases in animal and dietary protein intake.

Men. The risk of kidney stones increases in a man's 40s and continues to rise until age 70. Caucasian men are at higher risk than other groups.

Women. The risk of kidney stones peaks in a woman's 50s. In younger women, stones are more likely to develop during the late stages of pregnancy. Pregnant women tend to have a higher calcium intake, but their kidneys do no handle the calcium as well as they did prior to pregnancy. Kidney stones are still a rare occurrence during pregnancy, however, affecting only 1 in 1,500 pregnancies.

Risk Factors in Children. Stones in the urinary tract in children are usually due to genetic factors. Most of the time, the cause is too much calcium in the urine (hypercalciuria). Deformities in the urinary tract pose a significant risk for kidney stones in children. Children with low birth weight who need to be fed intravenously are also at risk for stones.

Obesity and weight gain are both associated with an increased risk of kidney stones.

Men who weigh more than 220 lbs are 44% more likely to develop kidney stones than men who weigh less than 150 lbs.
Women who are obese are 90% more likely to develop kidney stones than women with a lower body mass index (BMI).

Higher BMIs and larger waist circumferences are both risk factors for kidney stones. Researchers think that there may be a link between fat tissue, insulin resistance, and urine composition. People with larger body sizes may excrete more calcium and uric acid, which increase the risk of kidney stone formation.

A family history of kidney stones increases one's risk for the condition. Researchers are looking into markers or other factors that might predict kidney stones in relatives, although none has yet been clearly identified. One report found that among the siblings of patients with calcium stones, sisters with higher urinary calcium levels and more acidic urine were more likely to develop stones. Brothers with high urinary calcium, low urinary potassium, and older age were more likely to have the problem. A family history of gout may also make a person vulnerable to stones.

According to a 2003 study of American ethnic groups, Caucasians have the highest incidence of kidney stones (5.9%) followed by Mexican Americans (2.6%). African-Americans have the lowest risk (1.7%).

Dietary factors, minerals in local water, or both may contribute to geographic differences that have been observed in the occurrence of kidney stones. Studies have reported the highest occurrence of kidney stones in the southern region of the United States and the lowest in the west. One study suggested that the higher risk may be due to a higher rate of high blood pressure in the southern states and certain dietary habits, particularly lower intake of magnesium and low use of calcium supplements.

Specific Foods. In general, certain foods increase the risk for stones only in people who have genetic or medical vulnerability. People whose diets are high in animal protein and low in fiber and fluids may be at higher risk for stones. A number of foods contain oxalic acid, but there is no proof that such foods make any major contribution to calcium oxalate stones in people without other risk factors. However, several studies have shown that increasing dietary calcium and restricting salt, animal protein, and foods rich in oxalate can help prevent calcium oxalate stones from returning.

Stress. One study reported that people who had a major, stressful life experience were more likely to develop stones than those who had not. Some experts speculate that this increased risk may be due to a hormone called vasopressin, which is released in response to stress. Vasopressin also increases the concentration of urine.

Sleep Position. Sleeping in the same position consistently may influence risk. A 2001 study reported that in people who had a history of kidney stones, recurrences tended to occur on the same side that people slept on. An earlier study suggested that people who had kidney stones were more apt to sleep on their stomachs. Movement during sleep did not appear to affect the risk.

Being Bedridden. Any medical or physical condition that keeps a person in bed or immobile increases blood levels of calcium from bone breakdown, thereby posing a risk for stone formation.

Gout. Patients with gout are at a high risk of uric acid stones. These patients have very acidic urine, and a 2002 study suggested that the two disorders may have a common source.

High Blood Pressure. Persons with high blood pressure are up to three times more likely to develop kidney stones. It is not entirely clear whether having high blood pressure increases the risk for a stone, whether stones lead to high blood pressure, or if there is an action linking both.

Inflammatory Bowel Disease: Crohn's disease and ulcerative colitis cause problems in absorption of substances in the intestines. These problems significantly increase the risk for kidney stones, particularly in men.

Urinary Tract Infections (UTIs): Urinary tract infections are almost always the cause of struvite stones.

Hyperparathyroidism: The parathyroid glands regulate calcium levels in the body through the parathyroid hormone. In hyperparathyroidism, one or more of these glands makes too much parathyroid hormone. Some people with hyperparathyroidism develop kidney stones. Surgery to remove the hyperactive parathyroid gland in such patients reduces the risk for stone formation, but the risk still remains high for some time after surgery.

Other Medical Conditions. Kidney disease, chronic diarrhea, certain cancers (such as leukemia and lymphoma), and sarcoidosis put people at higher risk for stones.

AIDS medications. Over 10% of persons with AIDS who take the medicine indinavir develop stones. The risk is even higher in patients with AIDS who also have hepatitis B, hepatitis C, or hemophilia, as well as those who are very thin or who take the antibiotic combination TMP-SMX. In one study of persons with AIDS who took a combination of indinavir, zidovudine, and lamivudine, 36% developed kidney stones.

Other Drugs. Kidney stones are a rare side effect of thyroid hormones and loop diuretics (drugs that increase urination). In fact, diuretics are also used to prevent calcium stones. Certain cancer chemotherapies can also cause kidney stones. Long-term use of medications, such as antacids, which change the acidic content of urine, may increase the risk for kidney stones.

Symptoms

In many cases, kidney stones do not produce symptoms. However, if a stone becomes stuck in the ureter (the thin tube between the bladder and the kidney), symptoms can be very severe. Often, they vary depending on the stone's location and its progress.

Kidney stone attacks tend to be most common late at night or in the early morning, possibly because of minimal urine output or constriction of the ureters during the early morning hours. Kidney stone attacks are least common during the late afternoon

Pain usually begins abruptly on one side and then usually continues as intense, constant pain. (In some cases it persists for a few minutes, disappears, and then returns after about 10 minutes.)
The patient cannot become comfortable and usually stands, sits, paces, or reclines in a vain search for a position that will bring relief.
If the stone is in the kidney or upper urinary tract, the pain usually starts in one flank area (to the side of the back near the waist). It typically moves to the groin as the stone passes down.
If the stone is too large to pass easily, the pain follows the muscle contractions in the wall of the ureter as they try to squeeze the stone along into the bladder.
Nausea and vomiting may occur.
Blood in the urine may be present.
As the stone passes down the ureter closer to the bladder, a person may feel the need to urinate more often or a burning sensation during urination.
If fever and chills accompany any of these symptoms, an infection may be present.

The size of the stone does not necessarily predict the severity of the pain; a very tiny crystal with sharp edges can cause intense pain while a larger round stone may not be as distressing. Struvite stones can often occur without symptoms.

Diagnosis

The doctor will perform a physical exam. This includes pressing against abdominal areas for tender locations that might indicate the presence of the stone.

The patient's age is a significant factor. Kidney stones that occur in children and young patients are more apt to result from inherited problems that cause cystine, xanthine, or, in some cases, calcium oxalate stones. In adult patients, calcium stones are most common.

A medical history may help predict which crystal has formed the stone. The doctor will need to know the following:

Any previous kidney stone attacks
Histories of cancer, sarcoidosis, or small bowel disease
Any medications being taken, including non-prescription substances, particularly high doses of vitamins D or C and calcium-containing antacids

Many conditions can cause symptoms similar to kidney stones. Usually the diagnosis is easily made because of the specific nature of the symptoms, but it is not always clear. Urinary tract infections can cause similar, but usually less intense, pain. In fact, infection may be present with a kidney stone. Other causes of pain that may mimic kidney stones include:

Gallstones
Diverticulitis (infection or irritation of abnormal pockets in the intestines)
Intestinal blockage
Blood clots
Irritable bowel syndrome
Appendicitis
Stomach ulcers
Hiatal hernia (when the upper part of the stomach bulges into the chest, through an opening in the diaphragm)
Pancreatitis (inflammation of the pancreas)
Hepatitis
Pelvic inflammatory disease
Inflammatory bowel disease (Crohn's and colitis)
Heart attack

Various imaging techniques are helpful in determining the presence of kidney stones. The best approach uses spiral (or helical) computed tomography scans. If it is not available, the patient will need ultrasound or standard x-rays. If no stones show up, but the patient has severe pain that suggests the presence of kidney stones, the next step is an intravenous pyelogram.

X-Rays. A standard x-ray of the kidneys, ureters, and bladder may be a good first step for identifying many stones, since many are visible on x-rays. Calcium stones can be identified on x-rays by their white color. Cystine crystals can also show up on x-rays.

Spiral (or Helical) Computed Tomography. A type of computed tomography (CT) scan, called a spiral or helical CT scan, is currently the best method for diagnosing stones in either the kidneys or the ureters. This test is fast, does not require instruments or foreign chemicals to enter the body, and provides detailed accurate images of even very small stones. If stones are not present, a spiral CT scan can often identify other causes of pain in the kidney area. It is better than x-rays, ultrasound, and intravenous pyelogram -- the previous standard test for detecting kidney stones. Experts hope spiral CT will eventually be able to identify the chemicals present in a stone.

Ultrasound. Ultrasound can detect clear uric acid stones and obstruction in the urinary tract. It is not useful for finding very small stones, but some research indicates that it may be a useful first diagnostic step in the emergency room to help predict the likelihood of a stone, including suspected stones in children.

Intravenous Pyelogram. With intravenous pyelogram (IVP), the doctor injects a special dye into the patient. A technician will then take x-rays as the dye enters the kidneys and travels down the urinary tract. IVP is invasive but, until recently, was the most cost-effective method for detecting stones. Where it is available, spiral CT is now preferred, since it gives a faster diagnosis, is more accurate, is safer, and is similar in cost.

In any case, IVP should not be used on patients with kidney failure. There is also a risk for an allergic reaction to standard dyes, although newer less allergenic ones are becoming available.

In the procedure intravenous pyelogram (IVP), the patient is injected with dye. X-rays are taken as the dye travels through the urinary tract. This procedure is done to confirm the presence of kidney stones, although some stones may be too small to see.

Magnetic Resonance Imaging. Magnetic resonance imaging (MRI) techniques are showing promise for diagnosing urinary tract obstruction but do not yet accurately reveal small stones, or ones that do not cause a blockage. Because no radiation is involved with MRI, however, it may prove to be a good option for pregnant women.

Urine samples are required to evaluate features of the urine, including its acidity and the presence of:

Red or white blood cells
Infection
Crystals
High or low levels of chemicals that inhibit or promote stone formation

Clean-Catch Urine Sample for Culturing. After determining that a kidney stone is present, the health care provider usually gives the patient a collection kit, including filters, to try to catch the stone or gravel as it passes out. The urine may also be tested (cultured) for the presence of infection-causing organisms. A clean-catch urine sample is almost always required for culturing. To provide a clean catch, do the following:

First, wash your hands thoroughly, then wash the penis or vulva and surrounding area four times with downward strokes, using a new soapy sponge each time.
Begin urinating into the toilet and stop after a few drops.
Position the container to catch the middle portion of the urine stream. Ideally, this urine will contain only the bacteria and other evidence of the stone.
Urinate the remainder into the toilet.
Tighten the cap on the container securely, being careful not to touch the inside of the rim.

Click the icon to see an image of a calcium urine test.

Twenty-Four Hour Urine Collection. A 24-hour urine collection may be needed to measure urine volume and levels of acidity, calcium, sodium, uric acid, oxalate, citrate, and creatinine.

You should not change any of your usual eating or drinking patterns when performing this test.
Discard the first urination on the day of the test.
Afterward all urine passed over the next 24 hours is collected, including the first urination on the morning of day two.
A second 24-hour urine collection may be needed to determine if treatment is working or if the first analysis was not conclusive and the doctor suspects a less common stone, such as a cystine or xanthine stone.

Click the icon to see an image of a uric acid urine test.

Urine tests that are used to determine the specific chemical and biological factors causing the stone should be performed about 6 weeks after the attack, since the attack itself may change the levels of such substances, including calcium, phosphate, and citrate. It should be noted that calcium levels in the urine may be abnormal even in many people without stones. In addition, high urinary concentrations of calcium may pose a greater or lesser risk depending on age. (In one 2001 study, middle-aged adults with high urinary calcium concentrations had a much greater risk than older adults with high levels.)

The kidney stones obtained from the urine sample are examined under a microscope. The crystal formations are often specific enough so that the doctor is able to identify the substance causing the stone.

Calcium oxalate crystals are eight-sided, while calcium phosphate crystals tend to have irregular shapes.
Uric acid stones are sometimes described as pear-shaped or diamond-shaped.
Some struvite stones have very specific shapes commonly described as "coffin lids." Struvite crystals may also occur in a formation known as a staghorn, which can be large and damaging to the kidney.

Testing whether urine is acidic or alkaline helps to identify the specific type of stone. The levels of acidity or alkalinity in any solution, including urine, are indicated by the pH scale:

A pH value of 7.0 is neutral.
A solution with a low pH (below 7.0) is acidic. (A low pH favors uric acid and cystine stones.)
A solution with a high pH is alkaline. (A high pH favors calcium phosphate and struvite stones.)

A dipstick test for blood in the urine (called hematuria) is typically performed when patients appear in the emergency room with flank pain (the primary symptom of kidney stones). About a third of kidney stone patients, however, do not show blood in the urine, so other tests may be needed.

Blood Tests for Stone Factors. Blood and urine tests help determine what substances form the crystals. This allows the doctor to determine the appropriate treatment and preventive measures.

Blood tests may help determine blood levels of urea nitrogen, creatinine, calcium, phosphate, and uric acid for patients with known or suspected calcium oxalate stones. Doctors will usually schedule these tests about 6 weeks after the attack, in order to measure these substances when the stone has been passed, and the patient has been stabilized. This is particularly true in patients with recurrent stones.

Parathyroid Tests. Tests to detect parathyroid hormone levels are given if the doctor suspects hyperparathyroidism, based on other signs and symptoms.

Tests for Infection. A test result that shows a high white blood cell count might indicate infection. Such results, however, could be misleading, since the number of white blood cells could also increase in response to the extreme physical stress of a kidney stone attack.

Tests for Metabolic Problems. About half of children with stones have an identifiable metabolic disorder, which increases their risk of stone recurrence five-fold. Experts argue whether tests for metabolic disorders are routinely needed once the stone composition has been determined. Studies suggest the following:

People with recurrent calcium stones have a wide range of irregular blood or urine test results, indicating a variety of possible metabolic disorders. For example, calcium stones in middle-aged women may be due to parathyroid abnormalities.
Calcium phosphate stones most likely result from renal tubular acidosis.
People with non-calcium stones generally have identifiable metabolic disorders.
Determining the stone composition may be sufficient for treatment, and may help avoid unnecessary metabolic tests.

Treatment

When tests show there is a kidney stone, the next step is to determine treatment. The patient should be admitted to the emergency room if they have severe vomiting, fever, or symptoms of infection.

Strong opioid painkillers, such as meperidine (Demerol), are often required for a severe kidney stone attack. However, doctors will usually not give such drugs until they confirm the presence of a kidney stone on an x-ray. In some cases, powerful nonsteroidal anti-inflammatory drugs (NSAIDs) may work just as well as opioids, and they have fewer side effects. However, they do take longer to work.

In about 85% of patients, the kidney stones are small enough that they pass through normal urination, usually within 2 to 3 days. In some cases, a stone may take weeks to months to pass, although pain usually goes away before that.

The patient should drink plenty of water (two to three quarts a day) to help move the stone along, and take painkillers as needed. The doctor usually provides a collection kit with a filter and asks the patient to save any passed stones for testing.

If the stone has not passed in 2 - 3 days, the patient will need additional treatments. In some severe cases, hospitalization may be necessary.

Specific procedures vary depending on the size of the stone or complexity of the situation. Noninvasive procedures are proving to be very beneficial in eliminating stones, and have largely replaced invasive surgeries.

For small stones that are lodged in the lower part of the ureter, ureteroscopy or shock wave lithotripsy are the procedures of choice.
For larger stones, ureteroscopy, percutaneous nephrolithotomy, and shock wave lithotripsy are all potentially useful. The choice of any of these procedures depends on a number of factors, including location of the stone and the presence of any problems that caused the stone in the first place.
In some complicated cases, standard open surgical procedures (called nephrolithotomy) may be required.

See "Other Treatments" section for more information on kidney stone surgery.


Stone Type	Diet and Lifestyle	Medications	Procedures
Calcium Oxalate	Plenty of fluids. (Choose water, lemon juice. Avoid grapefruit, apple, and cranberry juice.) Limit the amount of protein and salt in the diet. Increase fiber. Limit the amount of fats in the diet, particularly in people who have short bowel syndrome. Balance normal calcium intake with potassium- and phosphate-rich foods. Limit the amount of calcium in the diet (only in people who have genetic abnormalities that cause high intestinal absorption of calcium). Limit the amount of foods high in oxalates (only in patients with rare intestinal conditions that cause hyperoxaluria).	Diuretics ("water pills"), Citrate salts, phosphates, cholestyramine.	Lithotripsy, uteroscopy, percutaneous nephrolithotomy, open surgery.
Uric Acid	Plenty of fluids. (Choose water, blackcurrant juice. Avoid cranberry juice.) Increase calcium intake (be sure well-balanced with potassium and phosphates). Reduce protein and other foods with high-purine content.	Potassium citrate, sodium bicarbonate, allopurinol.	Lithotripsy, uteroscopy, percutaneous nephrolithotomy, open surgery.
Struvite stones	Plenty of fluids (water, cranberry juice). Reduce proteins.	Antibiotics to eliminate any infection. Acetohydroxamic acid (AHA) may be helpful in combination with antibiotics. In some cases, organic acids given through urinary tract.	May respond poorly to most lithotripsy procedures and require open surgery. Newer procedures may be helpful.
Cystine stones	Very high fluid intake (four quarts a day). Limit the amount of protein in the diet.	Alkalizing agents (such as bicarbonate). Sometimes d-penicillamine, tiopronine, or captopril useful for lowering cystine levels.	May respond poorly to most lithotripsy procedures and require open surgery. Newer procedures may be helpful.

Medications

Diuretics. Diuretics are medicines commonly used to treat high blood pressure and other disorders. They remove fluid and sodium from the body. Low doses of a class of diuretics known as thiazides are sometimes used to reduce the amount of calcium released by the kidneys into the urine. Thiazides include:

Hydrochlorothiazide (Esidrix, HydroDiuril)
Chlorothiazide (Diuril)
Trichlormethiazide (Metahydrin, Naqua)
Chlorthalidone (Hygroton)

However, thiazides also cause potassium loss, which reduces citrate levels and can increase the risk for stones. Patients taking thiazide pills should also take potassium citrate, to prevent citrate loss. Amiloride (Midamor) is a potassium-sparing diuretic, which may be used if a thiazide does not work.

Citrates. Citrate salts are often given to people with calcium oxalate or uric acid stones:

Potassium magnesium citrate is available over the counter. It is proving to be very beneficial in preventing kidney stones. In one study, potassium magnesium citrate reduced the risk for kidney stone recurrence by 85%.
Potassium citrate (K-Lyte, Polycitra-K, Urocit-K) is given as the only treatment to people with normal urine calcium levels. Between 70 - 75% of patients with recurrent stones have ongoing remission (no stone recurrence) with potassium citrate treatment. However, some people cannot tolerate potassium citrate because of side effects (stomach problems).
Magnesium citrate (Citroma, Citro-Nesia) may help people who develop calcium stones from impaired intestinal absorption due to short bowel disease.

None of these products should be used by people with struvite stones, urinary tract infections, bleeding disorders, or kidney damage. Patients who take citrate supplements containing potassium should not take any other medications that either contain this mineral or prevent its loss (such as so-called potassium-sparing diuretics). People with peptic ulcers should avoid citrate supplements, or discuss using non-tablet forms with their doctor.

Phosphates. Phosphates help reduce the breakdown of bone that releases calcium into the bloodstream. They are also involved in the kidney's reabsorption of calcium from the urine.

Phosphate compounds:

Neutral (nonacidic) sodium or potassium phosphate (K-Phos, Neutral, Neutra-Phos) is usually taken four times a day after meals to prevent kidney stones unless otherwise directed by the doctor. Diarrhea is a possible side effect.
Cellulose phosphate (Calcibind) is recommended only for severe hypercalciuria that is associated with recurrent calcium stones and is caused by excessive absorption of calcium from the intestines. However, this drug may increase oxalate levels and decrease magnesium levels, which can lead to different stones. Taking magnesium supplements and reducing dietary oxalates, calcium, and ascorbic acid may help offset these risks. Cellulose phosphate may also cause bloating.

Avoid acidic forms of phosphate, since they increase the risks for both hypocitraturia and hypercalciuria.

Cholestyramine (Questran, Questran Light) is a drug used to reduce cholesterol levels. However, it also binds with oxalate in the intestine, so it is also used to reduce high oxalate levels in urine (hyperoxaluria). The drug usually comes in a powder that is dissolved in liquid.

Bloating and constipation are common side effects of this drug. Cholestyramine also interferes with other medications, including digoxin (Lanoxin) and warfarin, and may contribute to calcium loss and osteoporosis. In order to prevent such interactions, take other drugs 1 hour before, or 4 - 6 hours after, taking cholestyramine.

Long-term use of cholestyramine may cause deficiencies of vitamins A, D, E, and K. Vitamin supplements may be necessary.

Sodium Bicarbonate. Patients whose persistently acidic urine causes uric acid stones may take sodium bicarbonate to reduce urine acidity. Patients taking sodium bicarbonate must test their urine regularly with pH paper, which turns different colors depending on whether the urine is acidic or alkaline. Too much sodium bicarbonate can cause the urine to become too alkaline. This increases the risk for calcium phosphate stones. Patients who need to reduce the amount of sodium they take in (as a result of other medical conditions) should not use sodium bicarbonate.

Potassium Citrate. Potassium citrate, which restores citrate to the urine, is useful for patients with high levels of uric acid in the urine.

Allopurinol. Allopurinol (Lupurin, Zyloprim) is very effective in reducing high levels of uric acid, and may be helpful for patients with uric acid stones. Allopurinol will not prevent calcium stones from forming. There is also a slight risk for the formation of xanthine stones with this drug. Side effects include diarrhea, headache, and fever. More severe complications include blood disorders that may produce fatigue, bleeding, or bruising. The drug may also increase the risk for cataracts.

About 2% of patients experience an allergic reaction to allopurinol that causes a rash. In rare cases, the rash can become severe and widespread enough to be life threatening. Allergic individuals who have experienced only a mild rash to sodium bicarbonate may be able to build up their tolerance for allopurinol by undergoing a desensitization process. In this process, patients start with small doses of allopurinol and gradually increase them, if no reaction develops.

Allopurinol reduces uric acid levels rapidly, so it may trigger an attack of gout in vulnerable people. To prevent this problem, patients taking allopurinol should also take a nonsteroidal anti-inflammatory drug (NSAID) for 2 or 3 months. Aspirin should not be taken, since it increases uric acid levels. Patients should discuss the appropriate NSAID choice with their doctor.

Before patients can receive any medical treatment for struvite stones, they must have surgery to completely remove the stones.

Antibiotics for Eliminating Infection. Persons with struvite stones receive ongoing treatment with antibiotics to keep the urine free of the bacteria that cause urinary tract infections. Careful follow-up and urine testing is extremely important. A high-pH urine indicates low acidity and an increased risk of infection.

Acetohydroxamic Acid (AHA). Acetohydroxamic acid (AHA or Lithostat) is beneficial when used with long-term antibiotics. AHA blocks enzymes that bacteria release, and has been effective in preventing stones even when bacteria are present. Side effects, however, can be severe. The drug reduces iron levels in the body, so anemia is a common problem. Patients may need to take iron supplements. Other side effects include nausea, vomiting, depression, anxiety, rash, persistent headache, and, rarely, small blood clots in the legs.

Experts recommend this drug only for patients with healthy kidneys who have chronic diseases caused by specific struvite-causing organisms.

Patients taking this medicine should avoid alcohol. Pregnant women should not take acetohydroxamic acid.

Organic Acids. Medical treatments to dissolve stones may be useful in patients who do not respond to other medications, or in combination with surgeries. Acidic urine dissolves struvite stones, so the doctor may wash the urinary tract with a solution of organic acids (such as Renacidin). Candidates for such washes must have sterile urine (no bacteria or other organisms in the urine) and healthy kidney function. In surgical patients, the wash is performed 4 or 5 days after the operation. The wash starts with saline (salt solution) for 1 - 2 days and, if there are no problems, the organic acid solution follows for another 1 or 2 days, until all stones dissolve. Regular urine tests are necessary to ensure that the bacteria do not return.

Aluminum Hydroxide Gel. An aluminum hydroxide anti-acid gel may reduce phosphate levels that are important in struvite stone formation, but it has a long-term risk of causing aluminum toxicity. Long-term reduction of phosphorus can also increase the risk for calcium oxalate stones. Experts recommend limiting phosphorus through a low-protein diet, rather than through the use of this gel.

The first-line treatment for cystine stones is increasing the alkalization of urine so the stones can dissolve. If alkalization fails, drug treatments may include d-penicillamine, alpha-mercaptopropionylglycine (tiopronine), or captopril. These medications lower cystine concentration.

Patients with cystine stones must drink plenty of fluids, much more than patients with other stones. The patients should drink at least four quarts of water over a 24-hour period.

Other Treatments

Surgery is usually needed if the stone is too large to pass on its own, if there are signs that the stone is growing, or if the stone is blocking the urine flow and causing a urinary tract infection or kidney damage.

Until recently, the procedure to remove a stone was a very painful, major surgery, requiring 4-6 weeks of recovery. Today, treatments for stones are much less invasive. Major surgery is performed in less than 2% of patients.

Stone removal procedures:

Extracorporeal shock wave lithotripsy (ESWL) is used for small stones (less than one centimeter, or slightly less than half an inch) that occur in the upper part of the ureter and do not pass on their own. One study indicated lithotripsy might even be safe and effective for patients whose stones are associated with malformed kidneys, although such patients are at higher risk for stone recurrence and should be carefully monitored.
Percutaneous nephrolithotomy (PNL). PNL can be used for very large stones in the upper urinary tract, when ESWL fails, for kidney transplant patients, or when the kidneys or surrounding areas are malformed. PNL is the preferred procedure for drug-resistant cystine stones, which are usually also resistant to shock wave therapy.
Ureteroscopy. For stones in the lower tract, ureteroscopy is generally the best procedure, although lithotripsy is also usually feasible and patients ordinarily prefer it.
Standard open surgery (nephrolithotomy) may be required if any of these procedures fail or are not appropriate, or in special cases, such as when the patient is very obese.

Most procedures are more effective for calcium and uric acid stones and less effective for struvite and cystine stones, although new techniques may be improving their effects on all stones.

Extracorporeal shock wave lithotripsy (ESWL) is a technique that uses sound waves (ultrasound) to break up simple stones in the kidney or upper urinary tract. ("Extracorporeal" means "outside the body," and "lithotripsy" means stone-breaking.) ESWL is not used for cystine stones. The procedure generally does not work for stones larger than three centimeters in diameter (which is slightly over an inch). There are several variations of ESWL. The following is a typical procedure:

Most ESWL procedures use some anesthesia, although they are often done on an outpatient basis.
The patient is positioned in a water bath. (In some procedures the patient lies on a soft cushion.)
The procedure uses ultrasound to generate shock waves that travel through the skin and body tissues until they hit the dense stones. (The doctor pinpoints the stone during treatment by using x-rays or ultrasound.)
The shock waves crush the stones into tiny sand-like pieces that usually pass easily through the urinary tract.
The shattered stone fragments may cause discomfort as they pass through the urinary tract. In such cases, the doctor may insert a small tube called a stent through the bladder into the ureter to help the fragments pass. This practice, however, has not proved to speed up passage of the stones in most cases and is not used routinely.

Extracorporeal shock wave lithotripsy (ESWL) is a procedure used to shatter simple stones in the kidney or upper urinary tract. Ultrasonic waves are passed through the body until they strike the dense stones. Pulses of sonic waves pulverize the stones, which are then more easily passed through the ureter and out of the body in the urine.

Success rates of ESWL range from 50 - 90%, depending on the location of the stone and the surgeon's technique and level of experience. Recovery time is short, and most people can resume normal activities in a few days.

Complications. Complications may include the following:

The most common complication is blood in the urine, which lasts for a few days after treatment. To reduce the chances of bleeding, doctors usually tell patients to avoid taking aspirin and other NSAIDs, which can promote bleeding, for 7 - 10 days before the treatment.
Bruising and minor discomfort due to the shock waves are common in the back or abdomen.
Sometimes the stone does not completely break up with one treatment, and additional treatments may be required. Inability to pass stone fragments may also be a particular problem in patients who have cysts or other kidney problems.
Higher risk for diabetes later. A 2006 study published in the journal Urology found that 17% of patients who received shock-wave lithotripsy developed diabetes later in life. The diabetes risk was related to the number and intensity of shocks.
Higher risk for hypertension (high blood pressure). The same study that linked ESWL to diabetes also showed that people who received shock-wave lithotripsy treatment were 47% more likely to develop high blood pressure than those who had their stones treated without surgery.

ESWL appears to be safe for children, although a 2001 study reported temporary damage in the kidney tubules after treatment. It is unclear if this complication has any long-term consequences. Experts recommend using the least amount of shocks and impact possible in young people. If more than one treatment is needed, there should be a waiting period of at least 15 days between treatments.

Percutaneous nephrolithotomy may be used when ESWL is not available or effective (such as if the stone is very large, in an inaccessible location, or is a cystine stone). It is also preferred over ESWL for stones that have remained in the ureter for more than 4 weeks.

It is more effective than ESWL for patients with severe obesity, and appears to be safe for the very elderly and the very young. Success rates are nearly 98% for kidney stones and 88% for ureteral stones. They may vary by the technique used and the specific patients. For example, success rates are slightly lower in children, although the procedure can be done safely in young patients. Long-term effects are unknown.

A typical procedure is as follows:

The surgeon makes a tiny incision in the back and creates a tunnel directly into the kidney.
The surgeon then inserts an instrument called a nephroscope through the tunnel.
The stone is located and removed. If it is large, it is destroyed using ultrasound, lasers, or other devices. The surgeon then removes the fragments. An advantage of percutaneous nephrolithotomy over ESWL is that the surgeon is able to remove the stone fragments directly, instead of relying on their natural passage from the kidney.
Generally, patients stay in the hospital for 5 or 6 days and may need a small device called a nephrostomy tube left in the kidney during the healing process.

Devices Used to Destroy Stones. For large stones, some type of energy-delivering device may be needed to break the stone into small pieces. They are referred to as intracorporeal lithotripsy devices (meaning stone breakers within the body). The device may be one of the following:

Ultrasound is currently the preferred method. It results in a stone-free rate of 94%. A rigid nephroscope delivers the ultrasound waves.
Pneumatic (compressed air) lithotripsy uses a probe that comes in direct contract with a stone. Compressed air causes a piston to collide rapidly with the probe, and the result is a "jackhammer" action against the stone, causing the stone to break up. This method, however, can send stone fragments into other parts of the urinary tract.
A more recent device uses a combination pneumatic probe and ultrasound, with stone-free rates of 80 - 89%. It may prove to be superior to ultrasound alone and be effective against stones of all types.
The holmium laser literally melts the stones and destroys up to 100% of stones of any composition. It uses a flexible nephroscope and has an excellent safety record. It should be used sparingly, however, with particular caution against large uric acid stones until more is understood about its effect. Another device, the erbium: YAG laser, although showing promise in lithotripsy, is not currently practical.

Complications. Complication rates are about 3%. Major complications occur in about 1% of cases. These complications may include scarring of the tissue, but studies indicate that it does not impair kidney function, even if the patient requires repeat surgery. There is also a risk for blood loss during and after the procedure, which, in some cases, can be significant.

Because the procedure requires large volumes of fluid, fluid overload is a potential problem, particularly in children or patients with heart disease.

In some cases, infection may result. Other complications may include a collapsed lung and injuries to areas outside the kidney (but within the operative area), such as the abdomen or chest.

Ureteroscopy may be used for stones in the middle and lower ureter. With the arrival of smaller instruments, this procedure can be done successfully in children as well. The procedure involves the following:

The patient receives a general anesthetic, though no incision is required for the procedure.
The surgeon passes a small fiberoptic instrument called a ureteroscope through the urethra and bladder into the ureter.
The surgeon locates the stone or stones.
The surgeon can remove smaller stones by grasping them with small forceps. A laser or pneumatic device breaks up large stones.
The surgeon may decide to leave a small tube, or stent, in the ureter for a few days after treatment, to help the lining of the ureter heal.

Complication rates range from 10 - 20%, with major problems occurring in up to 6% of patients. In some cases, large stones are not broken up into small enough pieces. This can result in blockage of the urinary tract and possible kidney damage.

Imaging tests, such as ultrasound or spiral CT, are useful within 3 months to check for residual stones, and a second procedure may be required. The risk of complications is highest when the procedure is performed by less experienced surgeons, or if stones are found in the kidney. The risk for perforation of the ureter increases the longer the procedure takes.

Open surgery involves incisions through the patient's flank and into the kidney. The surgeon will cool the kidneys using ice. X-rays during the procedure help locate the stone. At the beginning of the surgery, the surgeon will isolate the arteries supplying the kidneys, ensuring they are not harmed during the surgery. The surgeon will then locate and remove the stone. The surgeon will also correct any blockage in the affected area. The surgery, called nephrolithotomy, is very invasive and is restricted to the following:

Patients with very large or complex stones that cannot be removed using less invasive measures
Very obese patients

Some centers report success with extracorporeal shock wave lithotripsy, however, in patients who would normally be nephrolithotomy candidates. Therefore, even these patients should discuss other options with their surgeon.

The procedure is not appropriate for patients with:

Bleeding or clotting disorders
Untreated widespread infection
Severe and chronic kidney insufficiency (unless removing the stone will improve kidney function)

Complications

Between 70 - 90% of crystals remain tiny enough so that they can travel through the urinary tract and leave the body in the urine without being noticed. When they do cause symptoms, however, kidney stones have been described as one of the most painful disorders to afflict humans. The pain they cause is sometimes called renal colic. ("Renal" means "kidney.")

Obstruction and Infection. Although kidney stones often lead to obstruction (blockage) of the urinary tract, the blockage is usually temporary and causes no lasting damage. In some cases, however, particularly if the obstruction progresses with no symptoms, infection may occur, which can be serious and need immediate attention.

Kidney Failure. It is very rare for kidney stones to cause kidney failure, although some people have risk factors that make them more vulnerable to this serious complication. Risk factors include the following:

Very frequent recurrences (such as in people with cystine stones or other inherited forms of kidney stone disorders)
Accompanying episodes of urinary tract infections with obstruction, a particular risk with struvite stones
A history of multiple urologic procedures for kidney stones
Greater size of the kidney stone gravel

Without preventive treatment, calcium stones recur in 10% of patients within a year of the first attack, and in half of patients within 5 - 7 years. Individual risk for recurrence, however, varies depending on the stone and the underlying condition. For example, a 15-year-old with inherited cystine stones has a very high risk for recurrence, while a middle-aged man with a first calcium oxalate stone has a good chance of never passing another.

Prevention

All individuals who have experienced kidney stones should take some specific preventive measures to prevent recurrence. The following are some general observations:

The most important dietary recommendations for reducing the risk for calcium stones are increasing fluid intake, restricting sodium, and reducing protein intake.
A lower risk for calcium stones is also associated with higher potassium intake.
A high calcium diet does not appear to increase the risk for kidney stones as long as it also contains plenty of fluids and dietary potassium and phosphate. (Increasing calcium alone may pose a modest risk for stones.)
Patients should try to correct any dietary habits that cause acidic or alkaline imbalances in the urine, which promote stone formation.

Because different kidney stone types may require specific dietary changes, patients should work with their doctors to develop an individualized plan. It is important to note that nutritional considerations are very important in preventing recurrence, and patients should be vigilant in complying with the proper diet.

Good voiding habits, particularly frequent urination, are important. Therefore, of all the preventive recommendations, drinking enough fluids is the most important guideline for people with any type of kidney stones.

In general, patients with calcium or uric acid stones should drink at least 10 full glasses of fluid each day (at least half should be water). This includes one with each meal and drinking fluids at night, even if it means getting up from sleep. Fluid intake should produce at least two and a half quarts of urine each day.
To prevent cystine stones, patients should drink even more water -- over a gallon, or 16 8-ounce cups, every day. Patients should drink this amount at regular intervals throughout the night and day.

In all cases, patients need more fluid after exertion and during times of stress. If they drink enough, the urine should be pale and almost watery, not dark and yellow.

Water. Although water is best, it may vary depending on its source. Variations in water itself may have different impacts. One study reported that drinking hard tap water increased urinary calcium concentration by 50% compared to soft bottled water. On the other hand, mineral water containing both calcium and magnesium may reduce several risk factors for both calcium and uric acid stone formation.

Juices and Specific Effects. Other beverages have various positive or negative effects, depending on the type of stone:

Lemon Juice: Drinking one-half cup of pure lemon juice (enough to make eight glasses of lemonade) every day raises citrate levels in the urine, which might protect against calcium stones. (While orange juice also increases citrate levels, it does not lower calcium and it raises oxalate levels. Therefore, it is not recommended.)
Cranberry and Apple Juice: Apple and cranberry juice contain oxalates, and both have been associated with a higher risk for calcium oxalate stones. Cranberry juice has properties that may increase the risk for both calcium oxalate and uric acid stones. On the other hand, cranberry juice helps prevent urinary tract infections and so may be helpful for reducing the risk for struvite and brushite stones. (These stones are far less common, however.)
Black Currant Juice: In one study, black currant juice reduced urine acidity and was associated with protection against uric acid stones.
Grapefruit Juice: A number of studies have found a risk for stones from drinking grapefruit juice. In one study, just one 8-ounce cup of grapefruit juice per day increased the risk for forming stones by 44%.

Other Beverages and Their Effects on Stone Formation.

Soft Drinks. Patients with stones should avoid cola drinks, since they can severely reduce citrate levels in the urine. Many soft drinks contain phosphoric acid, which increases the risk for stones. Some research shows that drinking one quart (less than three 12-ounce cans) of soda per week may increase a person's risk of developing stones by 15%.
Alcohol. Wine may be protective against kidney stones. A study conducted in Finland, suggests that the risk of developing stones also decreases with beer consumption. However, it is important to remember that beer is high in oxalates. Beer and other alcoholic beverages also contain purines, which may increase the specific risk for the less common uric acid stones in susceptible people. Binge drinking, in any case, increases uric acid and the risk for stones.
Coffee and Tea. Some research reported a lower risk for stones in people who drink tea and both regular and decaffeinated coffee.

A long-term 2002 study followed men with calcium oxalate stones and high levels of urinary calcium. The study found that a low-sodium, low-protein diet, containing normal levels of calcium, dramatically reduced the recurrence of stones compared to a diet that was simply low in calcium.

Salt Restriction. Because salt intake increases the amount of calcium in urine, patients with calcium stones should limit their sodium intake. Sodium may also increase levels of urate, the crystalline substance that can trigger formation of recurrent calcium oxalate stones. Although the relative contribution of limiting sodium intake has not been confirmed, some researchers believe that restricting sodium along with increasing fluid intake is the most important dietary measure for preventing stones.

Protein Restriction. Protein increases uric acid, calcium, and oxalate levels in the urine, and reduces citrate levels. Diets high in protein, particularly meat protein, have been consistently connected with kidney stones. (Meat protein has a higher sulfur content and produces more acid than vegetable protein.) A 2002 study of those following a high-protein, low-carbohydrate diet (such as the Atkins diet, for example), found dramatically increased levels of urinary uric acid and calcium after just several weeks. These effects put patients at higher risk for not just kidney stones, but possibly osteoporosis as well. According to Swiss studies, about a third of people at risk for calcium stones may have a sensitivity to meat proteins that causes mild hyperoxaluria.

Whether restricting meat protein alone has any protective value without restricting sodium as well is unknown. Most studies to date have found no difference in stone development between people with low and normal meat protein diets over four years. A 2000 study reported that only dramatic reductions in meat protein had any preventive effect against stone recurrence.

Although the precise role of dietary protein in kidney stones needs further clarification, it is reasonable for everyone to consume meat protein in moderation. People with struvite stones, who need to reduce phosphates in their diets, should also cut down on proteins.

Calcium from Foods. Dietary calcium recommendations for kidney stone prevention need to be determined on an individual basis. A doctor will suggest calcium guidelines based on a patient's age, gender, body size, and type of stone. Most studies indicate that dietary calcium (found in milk, yogurt, and cheese) protects against many types of calcium oxalate stones. Large studies of both men and women found that those with the highest intake of calcium from foods had a much lower risk for stones than those who had little calcium in their diets. A diet containing a normal amount of calcium, but reduced amounts of animal protein and salt, may protect against stones better than a low-calcium regimen. However, calcium metabolism changes as people age. Some studies suggest that a high calcium intake protects against kidney stones in men younger than age 60, but not in older men.

Dietary calcium may actually bind the oxalate in foods, preventing it from being absorbed into the blood and excreted into the urine. In a normal healthy diet, dairy products supply almost 80% of the daily calcium requirement. For people who have calcium stones associated with resorption (the breakdown of bone that releases calcium into the bloodstream), limiting calcium intake could cause further bone loss.

Calcium Supplements. Evidence on calcium supplements is mixed, although in general many studies suggest that they reduce oxalate levels and so help prevent calcium oxalate stones. One study suggested that taking 500 mg of calcium supplements a day regularly may "reprogram" the intestines to absorb less calcium and may therefore be protective. Experts generally agree that calcium supplementation within dosage recommendations (about 1,200 mg per day) remains safe. In one study, however, women who took calcium supplements had a 20% higher risk for stones. Research indicates that dosages of calcium above 2,000 mg per day are clearly associated with the formation of stones. Some experts speculate that this higher risk may occur because supplements are often taken in the morning, either without food or with breakfast, which is typically low in oxalates. Taking supplements with later meals may not produce the same risk.

Calcium Restriction in Certain Cases. Some patients, such as those whose stones are caused by genetic defects in which the intestine absorbs too much calcium, may need to limit calcium intake. More studies are needed to define this group precisely.

Fiber may be beneficial for people with kidney stones. In addition, some fiber-rich foods may contain compounds that help protect against kidney stones. A wide variety of high-fiber plant foods contain a compound called phytate (also called inositol hexaphosphate, InsP6, or IP6), which appears to help prevent crystallization of calcium salts, both oxalate and phosphate. Phytate is found in legumes and wheat and rice bran. (Soybeans are also rich in phytate but they are also very high in oxalates, so the overall effects of soy on kidney stones are not clear.)

A high intake of purines can increase the amount of uric acid in the urine. Those at risk for uric acid stones should reduce their intake of foods and beverages that contain purines. These include beer and other alcoholic beverages, anchovies, sardines, yeast, organ meats (such as liver and kidneys), legumes (including dried beans, peas, and soybeans), mushrooms, spinach, asparagus, cauliflower, and poultry.

Most people with calcium oxalate stones should not avoid oxalate-rich foods unless the doctor specifically recommends a restrictive diet. Oxalate binds with calcium in the intestine, which may actually reduce calcium absorption. Some studies, in fact, indicate that eating foods containing oxalates and calcium together may reduce the risk of stones. Most of the foods that contain oxalates are very important for good health. Limiting oxalates may be particularly harmful in people with bowel disorders marked by malabsorption.

Foods high in oxalic acid include beets, soy, beet tops, black tea, chenopodium, chocolate, cocoa, dried figs, ground pepper, lamb, lime peel, nuts, parsley, poppy seeds, purslane, rhubarb, sorrel, spinach, and Swiss chard.
Foods containing moderate amounts of oxalates include beans (green and wax), blackberries, blueberries, carrots, celery, coffee (roasted), concord grapes, currants, dandelion greens, endive, gooseberries, lemon peel, okra, green onions, oranges, green peppers, black raspberries, strawberries, and sweet potatoes.

Certain fats may play a beneficial or harmful role in specific cases of kidney stones.

Restricted Fats in Patients with Stones Associated with Bowel Disease. Patients who have stones associated with short-bowel syndrome should eat foods with lower amounts of fats and oxalates. If patients with short-bowel syndrome eat too much fat, calcium may bind to unabsorbed fat instead of to oxalates. This increased oxalate levels, resulting in increased risk of stone formation.

Fish Oil. Omega-3 fatty acids, found in oily fish like mackerel, salmon, and albacore tuna, have many health benefits, but the most current evidence suggests they do not help prevent kidney stones. A 2005 study of over 200,000 adults found that increased omega-3 fatty acid intake did not reduce kidney stone risk.

Vitamin B6. Vitamin B6, or pyridoxine, is used to treat people with primary hyperoxaluria, a severe inherited disorder. Patients should not try to treat themselves with vitamin B6. Very high doses (500 to 2,000 mg daily over long periods) can cause nerve damage, with loss of balance and numbness in the feet and hands. Food sources of vitamin B6 include meats, oily fish, poultry, whole grains, dried fortified cereals, soybeans, avocados, baked potatoes with skins, watermelon, plantains, bananas, peanuts, and brewer's yeast.

Vitamin C. Ascorbic acid (vitamin C) may change in the body to tiny crystals, called oxalates. These crystals do not dissolve. People with hyperoxaluria (too much oxalate in the urine) should avoid vitamin C supplements. Even for men with normal oxalate levels, higher consumption of vitamin C (more than 1,000 mg a day) may increase kidney stone risk.

Magnesium and potassium may help reduce the risk for kidney stones in men.

Because of an association between stress and kidney stones, relaxation and stress management techniques may also be beneficial.

Dietary Considerations. People with kidney stones appear to be more sensitive to certain foods than people who do not form kidney stones. Therefore, vulnerable people should make specific changes in their diet. They should work with their doctors to develop a dietary plan that fits their individual situation. Drinking plenty of fluids is important for preventing recurrence of any kidney stone.

Indications for Drug Treatments. If dietary treatments fail, drug therapy may be helpful. A number of drugs are available to prevent recurrences of calcium oxalate and other stones. Medications that inhibit the formation of stones include allopurinol, thiazide, potassium citrate, and potassium-magnesium citrate. In addition, drug treatments can sometimes also help prevent other complications related to stones, such as osteoporosis.

Correcting Underlying Conditions Known to Cause Kidney Stones. It is also important to treat and correct, if possible, any underlying disorder that may be causing stones to form. Such disorders include distal renal tubular acidosis, hyperthyroidism, sarcoidosis, and certain cancers. To prevent calcium stones that form in hyperparathyroid patients, a surgeon may remove the affected parathyroid gland (located in the neck). In most cases, only one of the glands is enlarged. Removing it ends the patient's problem with kidney stones.

Resources

www.kidney.niddk.nih.gov -- National Kidney and Urologic Diseases Information Clearinghouse
www.urologyhealth.org -- American Urological Association
www.kidney.org -- National Kidney Foundation
www.ohf.org -- Oxalosis and Hyperoxaluria Foundation

References

Cameron MA, Maalouf NM, Adams-Huet B, Moe OW, Sakhaee K. Urine composition in type 2 diabetes: predisposition to uric Acid nephrolithiasis. J Am Soc Nephrol. 2006 May;17(5):1422-8. Epub 2006 Apr 5.

Curhan GC, Willett WC, Knight EL, Stampfer MJ. Dietary factors and the risk of incident kidney stones in younger women: Nurses' Health Study II. Arch Intern Med. 2004;164(:885-891.

Finkielstein VA. Strategies for preventing calcium oxalate stones. CMAJ. 2006;174(10); 1407-1409.

Krambeck AE, Gettman MT, Rohlinger AL, Lohse CM, Patterson DE, Segura JW. Diabetes mellitus and hypertension associated with shock wave lithotripsy of renal and proximal ureteral stones at 19 years of followup. J Urol. 2006;175(5):1742-7.

Sinha MK, Collazo-Clavell ML, Rule A, et al. Hyperoxaluric nephrolithiasis is a complication of Roux-en-Y gastric bypass surgery. Kidney International. 2007;72:100-107.

Straub M, Hautmann RE. Developments in stone prevention. Curr Opin Urol. 2005;15(2):119-126.

Taylor EN, Stampfer MJ, Curhan GC. Dietary factors and the risk of incident kidney stones in men: new insights after 14 years of follow-up. J Am Soc Nephrol. 2004;15(12):3225-3232.

Taylor EN, Stampfer MJ, Curhan GC. Fatty acid intake and incident nephrolithiasis. Am J Kidney Dis. 2005;45(2):267-274.

Taylor EN, Stampfer MJ, Curhan GC. Obesity, weight gain, and the risk of kidney stones. JAMA. 2005;293(4):455-462.

Taylor EN, Stampfer MJ, Curhan GC. Diabetes mellitus and the risk of nephrolithiasis. Kidney Int. 2005 Sep;68(3):1230-5.

Wasserstein AG. Nephrolithiasis. American Journal of Kidney Diseases. 45(2);2005:422-28.

Review Date:
7/24/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

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Iron

FitSugar — Wed, 08 Oct 2008 17:35:25 -0700

Overview

Overview
Uses
Dietary Sources
Available Forms
How to Take It
Precautions
Possible Interactions
Supporting Research

HEALTH GUIDE REFERENCE FROM A.D.A.M

Overview

Iron is an essential mineral that contributes to many important physiologic functions in the body. Much of the iron in the body is attached to hemoglobin molecules in red blood cells, thereby delivering oxygen to all of the tissues. Extra iron is stored in the liver, bone marrow, spleen, and muscles.

Significant deficiency in iron leads to anemia. The most common symptoms of anemia are weakness and fatigue. Pregnant women, young women during their reproductive years, and children tend to be at the highest risk of becoming deficient in iron. Anemia may be mild, moderate, or severe and may be caused by significant or prolonged blood loss such as that from a bleeding ulcer, menstruation, severe trauma, surgery, or a malignant tumor. It can also be caused by an iron-poor diet, inefficient absorption of dietary iron, pregnancy, and the rapid growth that takes place during infancy, early childhood, and adolescence.

On the other hand, excessive iron in the body can lead to a condition known as hemochromatosis, which can cause diabetes, liver damage, and discoloration of the skin.

The World Health Organization (WHO) considers iron deficiency the number one nutritional disorder in the world. As many as 80% of the world's population may be iron deficient, while 30% may have iron deficiency anemia.

Uses

Anemia

The most important use of iron supplements is to treat anemia caused by iron deficiency. Anemia is low levels of iron in the blood. Iron is important, as it is a key component of hemoglobin, which carries oxygen to our tissues. Anemia can be caused by many conditions, including PMS and menopausal loss, pregnancy, blood donation, bleeding ulcers, surgery (before and after), and chronic diseases such as cancer and kidney failure. Anemia treatment is directed and supervised by a health care provider, who may first search for the underlying reason for the low levels of iron.

Exercise capacity

Low levels of iron can lead to diminished exercise capacity, whether anemia is present or not. Therefore, if your iron stores are low (as measured by your doctor), iron supplements (for example, in a multivitamin or iron supplement) may improve endurance during aerobic activities.

Attention-deficit hyperactivity disorder (ADHD)

Symptoms of iron deficiency (including decreased attention, arousal, and social responsiveness) are similar to symptoms of attention-deficit hyperactivity disorder (ADHD). There is little clinical evidence, however, that iron supplementation improves behavior in children with ADHD who are deficient in iron. Since iron can be toxic in children who are not deficient, there is little justification for its supplementation as a treatment for ADHD in children with normal levels of this mineral. If iron levels are low, a health care provider can determine whether replacement is needed.

Cough associated with ACE inhibitor use

One preliminary clinical study suggested that iron supplementation may soothe and even prevent cough associated with a class of medications known as angiotensin-converting enzyme (ACE) inhibitors, including enalapril (Vasotec), captopril (Capoten), and lisinopril (Zestril or Prinivil). ACE inhibitors are medications commonly used to treat high blood pressure and heart failure, but dry cough is a side effect that leads many people to discontinue their use. Despite this encouraging information, it is premature to conclude that taking iron with ACE inhibitors to reduce dry cough is safe or effective.

Plus, it is important to note that taking ACE inhibitors at the same time as iron may diminish the absorption of this nutrient. Therefore, if used together, the two should be taken at least two hours apart. Also, iron is associated with some risk for heart disease. For this reason, it should not be used by individuals with high blood pressure or heart failure without the consent and supervision of a doctor.

Infants and children

Iron deficiency is a significant public health problem in young children due to their high iron requirements, and iron supplements are therefore often recommended by health care providers. Iron deficiency may increase the risk of lead poisoning in children. However, the use of iron supplementation in lead poisoning is reserved for those individuals who are truly iron deficient or for those individuals with continuing lead exposure, such as continued residence in lead-exposed housing. Do not give iron supplements to infants or children under 18 unless under the supervision of a doctor.

Dietary Sources

The best dietary sources of iron are liver and other organ meats, lean red meat, poultry, fish, and shellfish (particularly oysters). Iron from these sources is readily absorbed in the intestines.

Other sources of iron include dried beans and peas, legumes, nuts and seeds, whole grains, dark molasses, and green leafy vegetables. However, iron from these sources must be accompanied by certain nutrients for proper absorption. For example, vitamin C helps the absorption of this type of iron while calcium (including all dairy products), bran, tea, and unprocessed whole grain products block its absorption.

In the U.S., grain products such as breads and cereals are fortified with iron to help increase amount in our diet.

Available Forms

Ferrous sulfate is the most common type of iron supplement. Other available forms include ferrous fumarate, ferrous succinate, ferrous gluconate, ferrous lactate, ferrous glutamate, ferric ammonium citrate, and ferrous glycine.

In severe cases of anemia from low levels of iron, or if there is rapid blood loss leading to iron deficiency, iron and blood will be administered intravenously (IV or in the veins) in a hospital setting.

How to Take It

Recommendations for iron are provided in the Dietary Reference Intakes (DRIs) developed by the Institute of Medicine of the National Academy of Sciences.

Infants and children (under 18 years of age)

Do not give iron supplements to infants or children under 18 unless under the supervision of a doctor.

For infants 7 – 12 months: The recommended dietary allowance is 11 mg daily.

For children 1 – 3 years: The recommended dietary allowance is 7 mg daily.

For children 4 – 8 years: The recommended dietary allowance is 10 mg daily.

For children 9 – 13 years: The recommended dietary allowance is 8 mg daily.

For male children 14 – 18 years: The recommended dietary allowance is 11 mg daily.

For female children 14 – 18 years: The recommended dietary allowance is 15 mg daily.

Iron in human breast milk is well absorbed by infants. It is estimated that infants can use greater than 50% of the iron in breast milk as compared to less than 12% of the iron in infant formula. The amount of iron in cow's milk is low, and infants poorly absorb it. Feeding cow's milk to infants also may result in gastrointestinal bleeding. For these reasons, cow's milk should not be fed to infants until they are at least 1 year old. The American Academy of Pediatrics (AAP) recommends that infants be exclusively breast fed for the first 6 months of life. Gradual introduction of iron-enriched solid foods should complement breast milk from 7 - 12 months of age. Infants weaned from breast milk before 12 months of age should receive iron-fortified infant formula. Infant formulas that contain from 4 -12 mg of iron per liter are considered iron-fortified.

Adult

For male adults 19 – 50 years: The recommended dietary allowance is 8 mg daily.

For female adults 19 – 50 years: The recommended dietary allowance is 18 mg daily.

For adults 51 years and older: The recommended dietary allowance is 8 mg daily.

For pregnant females ages 14 – 50 years: The recommended dietary allowance is 27 mg daily.

For lactating females ages 14 – 18 years: The recommended dietary allowance is 10 mg daily.

For lactating females ages 19 – 50 years: The recommended dietary allowance is 9 mg daily.

Precautions

Because of the potential for side effects and interactions with medications, dietary supplements should be taken only under the supervision of a knowledgeable health care provider.

The most common side effect from iron supplements is stomach upset, including discomfort, nausea, diarrhea, constipation, and heartburn.

Although not entirely clear, there may be an association between high iron stores and risk of heart disease, cancer (such as breast cancer), and Alzheimer's disease. Similarly, for those with inflammatory bowel disease (Crohn's disease and ulcerative colitis) the areas of the bowel that are inflamed appear to have higher amounts of iron. This is thought to be because iron acts as a pro-oxidant, stimulating the damaging effects in the body of substances known as free radicals.

Iron overload disease, although most commonly an inherited condition called hemochromatosis, may occur in people who consume excessive amounts of iron over a long period of time. Symptoms include skin discoloration, diabetes, and liver damage, among other potential complications. The U.S. Food and Drug Administration (FDA) has established that taking up to 45 mg of iron per day is safe. However, safety for amounts higher than 45 mg per day is not known. Severe iron overdose occurs when amounts of iron equivalent to 50 -100 times greater than the recommended dietary dose are ingested. Such iron toxicity can lead to destruction of cells in the gastrointestinal tract, which can cause vomiting, bloody diarrhea, and even death. Given the severity of potential adverse effects from excessive iron, supplements should be kept in childproof bottles and out of the reach of children.

Intravenous (into the veins) iron, administered in the case of severe anemia in a hospital setting, can lead to headache, fever, swollen lymph nodes, painful joints, hives, worsening of rheumatoid arthritis, and in rare instances a life-threatening allergic reaction known as anaphylaxis.

Possible Interactions

If you are currently being treated with any of the medications discussed below, you should not use iron without first talking to your health care provider.

Iron may interfere with the absorption of many different medications. For this reason, it is best to take iron supplements at least 2 hours before or 2 hours after taking medications. This is particularly true for the medications listed below.

The following medications may reduce the absorption of iron:

Cholestyramine and Colestipol -- These are two cholesterol-lowering medications known as bile acid sequestrants.

Medications used to treat ulcers or other stomach problems -- Examples of anti-ulcer medications include cimetidine (Tagamet), ranitidine (Zantac), famotidine (Pepcid), and nizatidine (Axid). These medications belong to a class of drugs known as H2 receptor blockers. They change the pH in the stomach and subsequently alter the absorption of iron. It is possible that this effect could occur with other antiulcer medications including antacids and proton pump inhibitors, including omeprazole (Prilosec).

Iron decreases the absorption of the following medications:

Tetracyclines -- These are a class of antibiotics that include doxycycline (Vibramycin), minocycline (Minocin), and tetracycline (Sumycin).

Quinolones -- These are a class of antibiotics that include ciprofloxacin (Cipro), norfloxacin (Noroxin), and levofloxacin (Levaquin).

ACE inhibitors -- These are a class of medications used to treat high blood pressure. Examples include captopril (Capoten), enalapril (Vasotec), and lisinopril (Zestril or Prinivil).

Iron may reduce the effectiveness or blood levels of the following medications:

Carbidopa and Levodopa -- Iron lowers blood levels of carbidopa and levedopa (Sinemet ) but it is unclear whether these changes lower the effectiveness of the drugs.

Levothyroxine -- Iron may decrease the effectiveness of this thyroid replacement hormone. A health care provider will monitor thyroid function closely in those taking iron supplements with thyroid medications, including Armour Thyroid and levothyroxine (Synthroid).

Iron levels may be increased by:

Birth control medications -- Birth control medicines, or oral contraceptives, may increase iron levels, thereby decreasing the need for extra iron. Be careful if you are taking oral contraceptives not to take multiple vitamins that contain iron.

Supporting Research

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Baumgaertel A. Alternative and controversial treatments for attention-deficit/hyperactivity disorder. Pediatr Clin of North Am. 1999;46(5):977-992.

Belton N. Iron deficiency in infants and young children. Professional Care of Mother and Child. 1995;5:69–71.

Brouwers J. Drug interactions with quinolone antibacterials. Drug Safety. 1992;7(4):268-281.

Campbell NR, Hasinoff BB, Meddings JB, Anderson WD, Robertson S, Granberg K. Ferrous sulfate reduces cimetidine absorption. Dig Dis Sci. 1993;38(5):950-954.

Christen Y. Oxidative stress and Alzheimer disease. Am J Clin Nutr. 2000;71(suppl):621S-629S.

Dayal M, Barnhart KT. Noncontraceptive benefits and therapeutic uses of the oral contraceptive pill. Semin Reprod Med. 2001;19(4):295-303.

Dietary Guidelines for Americans 2005. Rockville, MD: US Dept of Health and Human Services and US Dept of Agriculture; 2005.

Domellof M. Iron requirements, absorption and metabolism in infancy and childhood. Curr Opin Clin Nutr Metab Care. 2007;10(3):329-35.

Duffy SJ, Biegelsen ES, Holbrook M, et al. Iron chelation improves endothelial function in patients with coronary artery disease. Circulation. 2001;103(23):2799-2804.

Fleming DJ, Jacques PF, Dallal GE, et al. Dietary determinants of iron stores in a free-living elderly population: the Framingham Heart Study. Am J Clin Nutr. 1998;67:722–733.

The Food and Nutrition Information Center. National Agricultural Library (NAL), United States Department of Agriculture's (USDA) Agricultural Research Service (ARS).

Gera T, Sachdev HP, Nestel P, Sachdev SS. Effect of iron supplementation on haemoglobin response in children: systematic review of randomised controlled trials. J Pediatr Gastroenterol Nutr. 2007;44(4):468-86.

Hercberg S, Preziosi P, Galan P. Iron deficiency in Europe. Public Health Nutr. 2001;4(2B):537-545.

Hinton PS, Giordano C, Brownlie T, Haas JD. Iron supplementation improves endurance after training in iron depleted, nonanemic women. J Appl Physiol. 2000;88(3):1103-1111.

Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press. January 9, 2001.

Jensen JT, Speroff L. Health benefits of oral contraceptives. Obstet Gynecol Clin North Am. 2000;27(4):705-721.

Kara M, Hasinoff BB, McKay DW, et al. Clinical and chemical interactions between iron preparations and ciprofloxacin. Br J Clin Pharmacol. 1991;31(3):257-261.

Killip S, Bennett JM, Chambers MD. Iron deficiency anemia. Am Fam Physician. 2007;75(5):671-8.

Lee SC, Park SW, Kim DK, Lee SH, Hong KP. Iron supplementation inhibits cough associated with ACE inhibitors. Hypertension. 2001;38(2):166-170.

Li RC, Lo KN, Lam JS, et al. Effects of order of magnesium exposure on the postantibiotic effect and bactericidal activity of ciprofloxacin. J Chemother. 1999;11(4):243-247.

Liehr JG, Jones JS. Role of iron in estrogen-induced cancer. Curr Med Chem. 2001;8(7):839-849.

Lih-Brody L, Powell Sr, Collier KP, et al. Increased oxidative stress and decreased antioxidant defenses in mucosa of inflammatory bowel disease. Dig Dis Sci. 1996;41(10):2078-2086.

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