FitSugar

What's the Deal With the Morning Banana Diet?

FitSugar — Tue, 04 Nov 2008 03:30:00 -0800

I've been hearing a lot about this new Morning Banana Diet that is taking Japan by storm, so I decided to do a little investigating on whether or not it's worth all the hype.

Basically, the rules behind the Morning Banana Diet (MBD) are relatively simple. Eat at least one banana for breakfast and anything you like for lunch and dinner, as long as you don't eat after 8 p.m. An afternoon snack is OK (even if it's unhealthy), but no desserts after meals and you're encouraged to drink only room temperature water. You'll need to go to bed by midnight and keep a food journal. Exercise is not necessary, and you shouldn't force yourself to do it if it stresses you out (WTF?).

If you remember the general rules of for spotting an unhealthy diet, you probably also remember that all diets should promote healthy eating and exercise. Clearly, the MBD does not, and therefore does not get a thumbs-up in my book - not to mention the fact that it's really not something you could do for the rest of your life (I don't care how much you love bananas). Yes, bananas are good for you, but so is exercise, as well as a lot of other fruits and veggies that you could incorporate into your breakfast.

When you read about a new diet and it seems too good to be true, chances are it is - a silver bullet does not yet exist, and we'll know if and when it does. Until then, the real key to keeping yourself healthy is to maintain healthy eating and keep moving.

Source

Weight control and diet

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

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).

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A.D.A.M. Copyright

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997-2009 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

adam.com

Vitamins

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

In This Report

Highlights
Introduction
Carotenoids
Phytochemicals
Healthy Foods
Dietary Health Benefits
Resources
References

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

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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.

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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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Review Date:
10/29/2007
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

adam.com

High blood pressure

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

In This Report

Highlights
Introduction
Diagnosis
Causes
Risk Factors
Complications
Symptoms
Treatment
Lifestyle Changes
Medications
Classes of Medications
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Drug Approval

In 2007, the FDA approved a new type of high blood pressure drug. Aliskiren (Tekturna) blocks renin, a kidney enzyme that is associated with blood pressure regulation. Aliskiren can be taken alone or in combination with other blood pressure drugs, but it should not be used during pregnancy.

Drug Concerns

ACE inhibitors should never be taken during the second or third trimesters of pregnancy. An important 2006 New England Journal of Medicine study extended these concerns by reporting that ACE inhibitors may cause major heart birth defects during the first trimester. Although this research is still preliminary, the FDA and the American Heart Association now recommend that women who are pregnant or considering becoming pregnant switch to another type of blood pressure drug.
Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk of developing high blood pressure in men, suggests a 2007 Archives of Internal Medicine study. Previous research indicated that these non-prescription painkillers increase high blood pressure risk in women.

Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)

The ALLHAT trial has been the most important long-running clinical study for evaluating the effects of high blood pressure medications. One of its most critical findings established the importance of thiazide-type diuretics as first-line treatment for high blood pressure. Recent trial results indicate:

Diuretics are very helpful for preventing heart failure in patients with high blood pressure. In a 2006 Circulation study, diuretics outperformed ACE inhibitors and calcium channel blockers in reducing heart failure risk.
Thiazide-type diuretics may slightly increase the risk of developing diabetes more than other drug classes but their blood pressure-lowering benefits outweigh the risks, according to a 2006 Archives of Internal Medicine study. The study found that all types of blood pressure medications increase blood sugar levels and diabetes risk.

Introduction

High blood pressure, also called hypertension, is elevated pressure of the blood in the arteries. Hypertension results from two major factors, which can be present independently or together:

The heart pumps blood with excessive force
The body's smaller blood vessels (known as the arterioles) narrow, so that blood flow exerts more pressure against the vessels' walls

Blood pressure is the force applied against the walls of the arteries as the heart pumps blood through the body. The pressure is determined by the force and amount of blood pumped and the size and flexibility of the arteries.

Although the body can tolerate increased blood pressure for months and even years, eventually the heart may enlarge (a condition called hypertrophy), which is a major factor in heart failure.

Click the icon to see an image of hypertrophic cardiomyopathy.

Such pressure can also injure blood vessels in the heart, kidneys, the brain, and the eyes.

Two numbers are used to describe blood pressure: the systolic pressure (the higher and first number) and the diastolic pressure (the lower and second number). Health dangers from blood pressure may vary among different age groups and depending on whether systolic or diastolic pressure (or both) is elevated. A third measurement, pulse pressure, may also be important as an indicator of severity.

Blood pressure is measured in millimeters of mercury (mm Hg). According to current adult guidelines, blood pressure is categorized as normal, prehypertensive, and hypertensive (which is further divided into Stage 1 and 2, according to severity). People in normal health should have a blood pressure reading of 120/80 mm Hg or less. High blood pressure is generally considered to be a blood pressure reading greater than or equal to 140 mm Hg (systolic) or greater than or equal to 90 mm Hg (diastolic). Blood pressure readings in the prehypertension category (120-139 systolic or 80-89 diastolic) indicate an increased risk for developing hypertension.

Current guidelines for children are based on percentile ranges for a child’s body size. Hypertension is defined as average systolic and diastolic readings that are greater than the 95th percentile for gender, age, and height on at least three occasions. Prehypertension in children is diagnosed when average systolic or diastolic blood pressure levels are at least in the 90th percentile but less than the 95th percentile. For adolescents, as with adults, blood pressure readings greater than 120/80 are considered prehypertensive. Increasing rates of childhood obesity have lead to higher than average blood pressure levels in children.

American expert groups recommend treating any blood pressure above normal. Some experts are concerned, however, that such guidelines may unnecessarily increase the use of anti-hypertensive drugs. It is important that patients establish a relationship with a doctor whom they trust, to help them determine individual blood pressure goals and treatment regimens. For some patients, a decrease of a few points in blood pressure may not be worth the side effects caused by higher doses of anti-hypertensive drugs.

Systolic Blood Pressure. The systolic pressure (the first and higher number) is the force that blood exerts on the artery walls as the heart contracts to pump out the blood. High systolic pressure is now known to be a greater risk factor than diastolic pressure for heart, kidney, and circulatory complications and for death, particularly in middle-aged and elderly adults. The wider the spread between the systolic and diastolic measurements, the greater the danger.

Elevated systolic pressure may pose a significant danger for heart events and stroke events even when diastolic is normal -- a condition called isolated systolic hypertension. Isolated systolic hypertension is the most common form of hypertension in people older than age 50. In one study, it comprised 87% of hypertension cases in people between ages 50 and 59.

Diastolic Blood Pressure. The diastolic pressure (the second and lower number) is the measurement of force as the heart relaxes to allow the blood to flow into the heart. High diastolic pressure is a strong predictor of heart attack and stroke in young adults.

Pulse Pressure. Pulse pressure is the difference between the systolic and the diastolic readings. It appears to be an indicator of stiffness and inflammation in the blood-vessel walls. The greater the difference between systolic and diastolic numbers, the stiffer and more injured the vessels are thought to be. Although not yet used by doctors to determine treatment, evidence suggests that it may prove to be a strong predictor of heart problems, particularly in older adults. Some studies suggest that in people over 45 years old, every 10 mm Hg increase in pulse pressure increases the risk for stroke rises by 11%, cardiovascular disease by 10%, and overall mortality by 16%. (In younger adults the risks are even higher.)

Click the icon to see an animation about blood pressure.

Some experts categorize hypertension into the following types:

Essential Hypertension. Essential hypertension is also known as primary or idiopathic hypertension. About 90% of all high blood pressure cases are this type. The causes of essential hypertension are unknown but are based on complex processes in all major organs and systems, including the heart, blood vessels, nerves, hormones, and the kidneys.

Secondary Hypertension. Secondary hypertension comprises about 5% of high blood pressure cases. In this condition, the cause has been identified.

Isolated Systolic Hypertension. This occurs when systolic hypertension is over 140 mm Hg but diastolic pressure is normal. It is related to arteriosclerosis (hardening of the arteries).

Click the icon to see an image of atherosclerosis.

Pregnancy Induced Hypertension. This condition occurs during pregnancy if blood pressure increases by more than 15 mm Hg above normal.

White Coat Hypertension. This form of hypertension is elevated blood pressure that occurs only during a visit to the doctor's office, but not at home. It is a factor in about 20% of patients with mild hypertension. Although previously considered a relatively harmless condition, research now suggests that white-coat hypertension shares certain features with essential hypertension. Studies have even suggested that white-coat hypertension actually may pose a risk for future heart problems, although the increased danger appears to be small compared with the risk in those with steady mild hypertension.


Blood Pressure Category	Ranges for Most Adults (systolic/diastolic)
Normal Blood Pressure (systolic/diastolic)	Systolic below 120 mm Hg Diastolic below 80 mm Hg
Prehypertension (Formerly Normal to High-Normal Blood Pressure)	Systolic 120 - 139 mm Hg Diastolic 80 - 89 mm Hg (NOTE: 139/89 or below should be the minimum goal for everyone. People with diabetes or chronic kidney disease should strive for 130/80 or less.)
Mild Hypertension (Stage 1)	Systolic 140 - 159 mm Hg Diastolic 90 - 99 mm Hg
Moderate to Severe Hypertension (Stage 2)	Systolic over 160 mm Hg or Diastolic over 100 mm Hg
Note: If one of the measurements is in a higher category than the other, the higher measurement is usually used to determine the stage. For example, if systolic pressure is 165 (Stage 2) and diastolic is 92 (Stage 1), the patient would still be diagnosed with Stage 2 hypertension. It should be strongly noted that a high systolic pressure compared to a normal or low diastolic pressure should be a major focus of concern in most adults.

Diagnosis

Most physical exams include a blood pressure measurement. Patients should not smoke or drink caffeinated beverages within 30 minutes before their blood pressure measurement.

The standard instrument used to measure blood pressure is called a mercury sphygmomanometer. Measurements are given as units of mercury, which has filled the central column in standard sphygmomanometers for years. (Some people view the mercury sphygmomanometer as an environmental health hazard, but modern devices are designed to prevent mercury spillage.)
An inflatable cuff with a meter attached is placed around the patient's arm over the artery while the patient is seated. The inflated cuff briefly interrupts the flow of blood in the artery, which then resumes as the cuff is slowly deflated.
The person taking the blood pressure listens through a stethoscope for so-called Korotkoff sounds, which first appear as blood begins to flow through the artery and then change in tone and volume as the cuff is deflated.
If a first blood pressure reading is above normal, the health professional may take two or more measurements separated by 2 minutes with the patient sitting or lying down. Another measurement may be taken after the patient has been standing for 2 minutes.

To measure blood pressure, your doctor uses an instrument called a "sphygmomanometer," more often referred to as a blood pressure cuff. The cuff is wrapped around your upper arm and inflated to stop the flow of blood in your artery. As the cuff is slowly deflated, your doctor uses a stethoscope to listen to the blood pumping through the artery. These pumping sounds register on a gauge attached to the cuff. The first pumping sound your doctor hears is recorded as the systolic pressure, and the last sound is the diastolic pressure.

Although this test has been used for more than 90 years, it is not completely accurate or sensitive. The following factors can cause a falsely low pressure reading:

An arm cuff that is too wide
Recent exercise
Not smoking for a while after heavy, long-term smoking

Falsely high pressure can result from:

An arm cuff that is too small
Talking during the test
Recently consuming foods or beverages (such as coffee) that raise blood pressure

Office blood pressure readings taken by a doctor are more likely to be higher than readings measured at home. This so-called white-coat hypertension requires additional readings by a nurse or by the patient. Home monitoring improves the accuracy of a simple office measurement. An average of all the measurements will be considered in the diagnosis of hypertension. If high normal or high blood pressure persists, further tests should be performed to determine if the organs are affected.

Other Blood-Pressure Monitors. Alternative pressure-measuring aneroid and electronic devices are available. Aneroid instruments are round, compass-like devices that use a metal spring to measure blood pressure and are often used by doctors. Electronic devices are typically used for home monitoring.

Monitoring Equipment. A number of home tests are available for checking blood pressure between doctor visits. A doctor may loan a patient a portable unit that records blood pressure during a full day's activity. This test, known as ambulatory monitoring, is particularly useful for those who experience wide blood pressure swings, such as those who have white-coat hypertension or show resistance to drug therapy. According to one study, accurately measuring blood pressure at home over a full day was a significantly better predictor of cardiovascular risk than standard office-based measurements. To improve clinical outcomes, devices are now available that allow 24-hour ambulatory blood pressure monitoring and electronically store results for analysis by the doctor. It is not clear if their added benefits justify their expense, however.

Cuffs and Stethoscopes. Manual cuffs and stethoscopes are fairly accurate, but they require practice to use. The cuff must be the right size (one size does not fit all). Devices that use a digital readout and a cuff that can be electronically inflated and deflated are proving to be as accurate as a stethoscope.

Blood Pressure Variations at Home. In general, everyone's blood pressure varies in the same way throughout a given day. In monitoring at home, it is important to note these changes:

Blood pressure is usually highest at work.
It drops slightly at home.
It then normally dips to its lowest level during sleep. There are important exceptions. Certain people have a condition called nondipper hypertension, in which blood pressure does not fall at night. Postmenopausal women appear to be at particular risk for this phenomenon, and it may pose a special danger for heart disease and stroke (particularly in older African-American women). It has also been linked to salt-sensitivity and insulin resistance.

Click the icon to see an image of stroke.

Upon waking, pressure in most people typically increases suddenly. In people with severe high blood pressure, this is the highest risk period for heart attack and stroke.

Click the icon to see an image of a heart attack.

Some studies have reported that when patients record and report their own blood pressure, they are unreliable and don't always tell the truth. Despite the difficulties and controversy surrounding this issue, home blood pressure monitoring has been shown to encourage patients to use measures that control their blood pressure and thereby reduce the risk of cardiovascular events.

Click the icon to see an image about monitoring blood pressure.

If blood pressure is elevated, the doctor will check the patient's pulse rate, examine the neck for distended veins or an enlarged thyroid gland, check the heart for enlargement and murmurs, and examine the abdomen and the eyes.

Click the icon to see an image of the thyroid gland.

If hypertension is suspected, the doctor should obtain the following information:

A family and personal medical history, especially incidence of high blood pressure, stroke, heart problems, kidney disease, or diabetes.
Risk factors for heart disease and stroke, including tobacco use, salt intake, obesity, physical inactivity, and unhealthy cholesterol levels.
Any medications being taken.
Any symptom that might indicate so-called secondary hypertension (that is, caused by another disorder). Such symptoms include headache, heart palpitations, excessive sweating, muscle cramps or weakness, or excessive urination.
Any emotional or environmental factors that could affect blood pressure.

If a physical examination indicates hypertension, additional tests may help determine whether it is secondary hypertension or essential hypertension (no other disorder is present) and whether organ damage is present. They include the following:

Blood tests and a urinalysis. (Performed to check for a number of factors, including potassium levels, cholesterol, blood sugar, infection, kidney function, and other possible problems. Measuring blood levels of the protein creatinine, for example, is important for all hypertensive patients in order to determine kidney damage. Higher concentrations may also be an indicator of heart disease.)

An electrocardiogram (ECG).

Click the icon to see an image of an electrocardiogram.

An exercise stress test. This could be important for those with borderline hypertension. Stress-induced blood pressure in such patients has been associated with a risk for left ventricular hypertrophy, a serious complication in which the muscles on the left side of the heart become enlarged. Studies also suggest that an excessive rise in systolic pressure during exercise indicates a risk for coronary artery disease, and stroke.

Click the icon to see an image of blood pressure tests.

Causes

Hypertension is referred to as essential (primary) when the doctor is unable to identify a specific cause. It is by far the most common type of high blood pressure. The causes of this type are unknown but are likely to be a complex combination of genetic, environmental, and other factors.

Genetic Factors. A number of genetic factors or interactions between genes play a major role in essential hypertension. Experts think that the chromosomes (13 and 18) house the genes responsible for blood pressure regulation, although pinning down the range of specific genes involved in hypertension is more difficult.

Abnormalities in the Angiotensin-Renin-Aldosterone System. Genes under intense study are those that regulate a group of hormones known collectively as the angiotensin-renin-aldosterone system. This system influences all aspects of blood pressure control, including blood vessel contraction, sodium and water balance, and cell development in the heart.

Experts believed that this system evolved millions of years ago to protect early humans during drought or stress by retaining salt and water and narrowing blood vessels to ensure adequate blood flow and repair injured tissue. With industrialization, however, this system wreaks havoc on modern humans by intensifying the effects of high-salt diets and sedentary lifestyle. Of particular importance in these harmful responses are the hormone aldosterone and a peptide (a component of proteins) called angiotensin II.

Inherited Abnormalities in the Sympathetic Nervous System. Studies suggest that some people with essential hypertension may inherit abnormalities of the sympathetic nervous system. This is the part of the autonomic nervous system that controls heart rate, blood pressure, and the diameter of the blood vessels.

Insulin Resistance and Type 2 Diabetes. Hypertension is strongly associated with diabetes, both type 1 and type 2. Kidney damage is generally the cause of high blood pressure in type 1 diabetes. Obesity and insulin resistance are the factors associated with hypertension in type 2 diabetes, the more common type. People with type 2 diabetes generally have normal or high levels of insulin, a critical hormone in the metabolism of sugar. However, they are unable to use the insulin, the condition called insulin resistance. Without insulin, blood glucose (sugar) levels rise, the hallmark of diabetes.

Some research indicates that obesity is the one common element linking insulin, type 2 diabetes, and high blood pressure. Obesity is common in both type 2 diabetes and hypertension. Oddly, however, studies have found a stronger association between hypertension and insulin resistance in thin patients as well as overweight people with type 2 diabetes. Some research indicates that insulin resistance may cause sodium retention, a contributor to high blood pressure.

In any case, regardless of the causal connections, people who have insulin resistance or full-blown diabetes plus hypertension have a significantly greater chance for heart attack, kidney disease, and stroke than people who have only high blood pressure.

Obesity. Obesity on its own has a number of possible effects that could lead to hypertension. It may blunt certain actions of insulin that open blood vessels, and it may cause structural changes in the kidney and abnormal handling of sodium. It is also associated with alterations in the systems that regulate blood flow.

Low Levels of Nitric Oxide. The gas nitric oxide can be produced in the body, where it affects the smooth muscle cells that line blood vessels; it helps keep them relaxed, flexible. It may also help prevent blood clotting. Low levels of nitric oxide have been observed in people with high blood pressure (particularly in African-Americans) and may be an important factor in essential hypertension.

Secondary hypertension has recognizable causes, which are usually treatable or reversible.

Medical Conditions. A number of medical conditions can cause secondary high blood pressure:

Kidney disease is the most common cause of secondary hypertension, particularly in older people.
Sleep apnea, a disorder in which breathing halts briefly but repeatedly during sleep, is now highly associated with hypertension. A weak but still higher than normal association with high blood pressure has even been observed in those who snore or have mild sleep apnea. The relationship between sleep apnea and hypertension has been thought to be largely due to obesity, but major studies are finding a higher rate of hypertension in people with sleep apnea regardless of their weight. Treating sleep apnea with a device known as nasal continuous positive airway pressure (CPAP) may have modest benefits blood pressure as well.

CPAP is an airway treatment using slight positive pressure during inhalation to increase the volume of inspired air and to decrease the work of breathing.

Other medical conditions that contribute to temporary hypertension are pregnancy, cirrhosis, and Cushing's disease.

Click the icon to see an image of cirrhosis of the liver.

Medications. Certain prescription and over-the-counter drugs can cause temporary high blood pressure. They include:

Corticosteroids
Acetaminophen (Tylenol)
Nonsteroidal anti-inflammatory drugs (NSAIDs) -- such as ibuprofen (Motrin), naproxen (Aleve), and aspirin -- may cause secondary hypertension as well as other complications. In one important study, women who used an NSAID for 5 or more days a month had a significantly higher risk for hypertension. The more often they used these drugs, the higher the risk. A 2007 study indicated that NSAIDs also increase the risk for hypertension in men. A 2005 study found that NSAIDs increase the risk for kidney failure, and that the risk is significantly greater for all patients with hypertension. Patients who took diuretics along with NSAIDs had 11.6 times the risk of developing acute kidney failure compared to non-NSAID users. The relative risk for calcium channel blockers and NSAIDs was 7.8. The researchers advised that NSAIDs should be used with caution in patients with hypertension or heart failure.
Cold medicines containing pseudoephedrine have also been found to increase blood pressure in hypertensive people, although they appear to pose no danger for those with normal blood pressure.
Oral contraceptives ("the pill") increase the risk for high blood pressure, particularly in women who are older, obese, smokers, or some combination. Stopping the pill nearly always reduces blood pressure, although a recent study suggested that oral contraceptives may produce a small but significant increase in diastolic pressure that persists in some older women who have been off the pill for years.

Alcohol, Cigarettes, and Coffee

An estimated 10% of hypertension cases are caused by alcohol abuse (three or more alcohol drinks a day), with heavier drinkers having higher pressure. Women may be more sensitive than men to the blood pressure effects of alcohol. Moderate drinking (one or two drinks a day) has benefits for the heart and may even protect against some types of stroke. In particular, red wine may have chemicals that help blood pressure.
Smoking. Smoking is a major risk factor. One study reported that smokers have blood pressures up to 10 points higher than nonsmokers.
Caffeine. In healthy people with normal blood pressure, drinking a couple of cups of coffee a day is unlikely to do any harm. A high intake of coffee may be harmful in people with hypertension and may even increase their risk for stroke.

Other Causes of Secondary High Blood Pressure

Stress
Intense workouts (snow shoveling, jogging, speed walking, tennis, heavy lifting, heavy gardening)

Risk Factors

During the last decade, the number of Americans with high blood pressure has increased by 30%. Over 65 million American adults now have high blood pressure, and this condition affects close to 1 billion people worldwide. Less than half of these people are on medication, however, and only about half of this group have their blood pressure under good control with such drugs. Older people are less likely to be treated adequately. The majority of people with high blood pressure have the mild type, but even this condition requires attention.

Age is the major risk factor of hypertension. Blood pressure increases with age in both men and women, and in fact, the lifetime risk for hypertension is nearly 90%. Two-thirds of Americans over age 60 have hypertension. Older women (60 years and above) currently have the highest rates of hypertension, and mortality rates from hypertension are higher in women than in men. Hypertension is also becoming more common in children and teenagers.

Compared to Caucasians, African Americans have 1.8 times the rate of fatal stroke, 1.5 times the risk for fatal heart disease, and 4.2 times the rates of end-stage kidney disease. In general, about 34% of African American men and women have hypertension; it may account for over 40% of all deaths in this group.

The prevalence of high blood pressure among African Americans is among the highest in the world. The rates of hypertension in Hispanic Americans, Caucasians, and Native Americans are about equivalent (ranging from 24 - 27%). The rate is much lower in Asian/ Pacific Islanders (9.7% in men and 8.4% in women). However, nearly 75% of older Japanese American men are hypertensive.

A number of theories have addressed the reasons for this difference:

African Americans may have lower levels of nitric oxide and higher levels of a peptide called endothelin-1 (ET-1) than Caucasians. Nitric oxide keeps blood vessels flexible and open and ET-1 narrows blood vessels.
African Americans have a higher risk for an impaired response to angiotensin (Ang II), which is a peptide important in regulating salt and water balances. African Americans are more likely to be salt-sensitive than other groups.
Social and income disparities and dietary issues may explain many of the differences in blood pressure rates observed between ethnic groups. For example, while African Americans have a disproportionately high rate of hypertension, one study in rural African villages, where diets are rich in fish, reported only a 3% rate of high blood pressure among inhabitants. Another study reported that Caucasian as well as African Americans in the Southeast have a higher incidence of hypertension and stroke than people in other U.S. regions. The Southeast also has a higher rate of obesity, stress, anxiety, and depression, and diets low in potassium and high in salt, all related to a lower socioeconomic level.
African Americans have a higher prevalence of risk factors (cardiovascular disease, obesity, diabetes and kidney disease) that are associated with hypertension.

In any case, hypertension appears to be dangerously undertreated in major minority groups. Inadequately controlled hypertension is the major factor for the higher mortality rate from heart disease among African Americans, and special treatment considerations need to be addressed in this population. A 2003 treatment consensus statement released by the International Society on Hypertension in Blacks (ISHIB) advises that many African Americans may need at least two medications to help lower their blood pressure. The ISHIB's "15 over 10" rule recommends combination therapy for any patient whose blood pressure exceeds their desired goal by 15 mm Hg systolic or 10 mm Hg diastolic.

Obesity. About one-third of patients with high blood pressure are overweight. Even moderately obese adults have double the risk of hypertension than people with normal weights. Moreover, the increase in blood pressure in aging Americans may be due primarily to weight gain. (In other cultures old age does not necessarily coincide with weight gain or high blood pressure.) Children and adolescents who are obese are at greater risk for high blood pressure when they reach adulthood.

Thinness. Interestingly, thin people with hypertension are at higher risk for heart attacks and stroke than obese people with high blood pressure. Experts think that thin people with hypertension are likely to have conditions such as an enlarged heart or stiff arteries that cause the blood pressure to rise and also pose greater dangers to health.

Low Birth Weight. Low birth weight, particularly in girls, has been associated with high blood pressure in both childhood and adulthood. One study suggested that breast-feeding these babies may help reduce this risk. Another study reported high levels of stress hormones in babies with low birth weight, which could increase the risk for high blood pressure later on. Low birth weight is also associated with subsequent obesity, a major contributor to hypertension.

Up to 75% of cardiovascular problems in people with diabetes may be due to hypertension. There are strong biologic links between insulin resistance (with or without diabetes) and hypertension. It is unclear which condition causes the other. Some experts believe angiotensin may be the common factor linking diabetes and high blood pressure. This natural chemical not only influences all aspects of blood pressure control but also interferes with insulin's normal metabolic signaling. People with diabetes or chronic kidney disease need to reduce their blood pressure to 130/80 mm Hg or lower to protect the heart and help prevent other complications common to both diseases. Lowering systolic pressure may be particularly important for people with diabetes.

Spouses. Studies suggest that spouses of people with high blood pressure are at a much higher risk as well. Such findings indicate that dietary and environmental factors play a role in this disease. Some evidence also indicates that higher risk in spouses may be due to people often choosing mates who are similar to them.

Family History and Genetics. Essential hypertension may be inherited in 30 - 60% of cases. According to one study, being a brother or sister of someone with premature coronary artery disease is a greater risk factor for hypertension than having a parent with the disease. A family history of heart disease is considered to be a major risk factor for high blood pressure in adults under age 65.

Atherosclerosis is a common disorder of the arteries. Fat, cholesterol, and other substances collect in the walls of arteries. Larger accumulations are called atheromas or plaque and can damage artery walls and block blood flow. Severely restricted blood flow in the heart muscle leads to symptoms such as chest pain.

People who are anxious or depressed may have over twice the risk for high blood pressure than those without these problems.

Mental Stress. Recent evidence confirms the association between stress and hypertension. In one 20-year study, men who periodically measured highest on the stress scale were twice as likely to have high blood pressure as those with normal stress. The effects of stress on blood pressure in women were less clear. Job stress and lack of career success have been specifically linked to high blood pressure in both men and women.

Anxiety. Studies suggest that anxiety is a risk factor for hypertension, particularly in women.

Depression. Mounting evidence suggests that depression has physiological effects that impair the heart and that it contributes to destructive behaviors, such as weight gain, smoking, or alcohol abuse. In one study, those who scored highest on a depression test had about twice the risk of high blood pressure as those with the lowest score. This link was particularly strong in African Americans. Depression was the strongest risk factor in this group.

Blood pressure levels tend to be lowest during the morning and midday hours and highest at the end of the day. Seasonal changes also affect blood pressure, with hypertension increasing during cold months and declining during the summer. Blood pressure readings can vary by as much as 40% depending on the time of day and season.

Complications

Hypertension places stress on several organs (called target organs), including the kidneys, eyes, and heart, causing them to deteriorate over time. High blood pressure contributes to 75% of all strokes and heart attacks. It is particularly deadly in African-Americans.

Research suggests that prehypertension is also a serious risk factor for heart complications. A 2005 study found that people with prehypertension are three times more likely to have a heart attack, and nearly twice as likely to develop coronary artery disease as people with normal blood pressure.

Hypertension is a disorder characterized by chronically high blood pressure. It must be monitored, treated and controlled by medication, lifestyle changes, or a combination of both.

Malignant hypertension, an emergency condition resulting from untreated primary hypertension, can be lethal.

About two-thirds of people who suffer a first stroke have moderate elevated blood pressure (160/95 mm Hg) or above. Hypertensive people have up to 10 times the normal risk of stroke, depending on the severity of the blood pressure. Hypertension is also an important cause of so-called silent cerebral infarcts, blockages in the blood vessels in the brain that may predict major stroke or progression to dementia over time.

Uncontrolled chronic high blood pressure is also associated with reduced short-term memory and mental abilities. Isolated systolic hypertension may pose a particular risk for complications in the brain. Fortunately, controlling blood pressure with medications can reduce or even prevent memory loss and mental decline due to hypertension. A 2006 study of older men indicated that anti-hypertensive treatment for at least 5 years may help prevent the development of dementia. Other studies suggest that anti-hypertensive drugs may help protect against Alzheimer's disease in people with genetic susceptibility to this disease.

High blood pressure is a major risk factor for heart disease.

Heart Attack. About half of people who suffer their first heart attack have moderate hypertension (160/95 mm Hg) or greater. High blood pressure increases the risk for a heart attack by up to five times, depending on the severity of the hypertension.

Heart Failure. Hypertension precedes heart failure in 75 - 90% of heart failure cases. High blood pressure has various effects that cause the heart to fail, including:

To compensate for increased blood pressure, the heart must work harder to pump blood, and so its muscles thicken (hypertrophy), usually on the left side (left-ventricle dysfunction). These thickened muscles pump inefficiently, and, over time, the force of their contractions weakens. The heart muscles then have difficulty relaxing and filling the heart with blood. The heart begins to fail.

Click the icon to see an image of a hypertensive heart.

The failing heart then triggers a number of hormonal and neurochemical mechanisms to correct imbalances in blood pressure and flow. This response, called remodeling, is helpful in the short run but very destructive and irreversible over time.
As part of the remodeling process, the heart muscle cells elongate. The muscular walls of the heart dilate and become thinner and inefficient. The cells themselves undergo molecular changes that result in calcium loss, a mineral crucial for healthy heart contractions.
The end-result of remodeling is a falling volume of blood pumped to the kidneys; the kidneys retain water and salt in response, increasing fluid buildup in the body.
To make matters worse, the body's arteries narrow in response to a lower blood volume. This constriction forces the heart to work even harder to pump blood through these narrowed vessels, increasing blood pressure and continuing the cycle.

A 2006 analysis of ALLHAT trial data indicated that diuretics are the best first-line high blood pressure medication for preventing heart failure.

Diabetes. High blood pressure, and the medications used to treat it, can increase the risk for developing diabetes. Studies have reported that thiazide diuretics and beta blockers carry a higher risk for causing diabetes than other anti-hypertensive drugs. However, an important 2006 ALLHAT study compared the effects of various drug classes on blood sugar levels and diabetes development. The results suggested that while diuretics may slightly increase diabetes risk more than other types of anti-hypertensive drugs, this effect does not cause worse heart problems. Most experts believe that thiazide diuretics should remain the first choice for high blood pressure treatment, and that the benefit of blood pressure reduction outweighs the risk of diabetes development.

Diabetes-Related Kidney Disease. High blood pressure is strongly associated with diabetic nephropathy (diabetes-related kidney disease). Most patients with type 2 diabetes who show early signs of nephropathy already have high blood pressure. When patients with type 1 diabetes are diagnosed with early nephropathy, on the other hand, they usually have normal blood pressure readings in the doctor's office. A 2002 study using home monitors, however, found that patients with type 1 diabetes often have high systolic blood pressure during sleep -- before development of nephropathy. Home blood pressure monitoring, then, may help identify patients who are at risk for kidney damage due to high systolic pressure.

End-Stage Kidney Disease. High blood pressure causes 30% of all cases of end-stage kidney disease (medically referred to as end-stage renal disease, or ESRD). Only diabetes leads to more cases of kidney failure.

Kidney Cancer. Men with high blood pressure may also have a higher risk of kidney cancer.

High blood pressure can injure the eyes, causing a condition called retinopathy.

Click the icon to see an image of hypertensive retinopathy.

Hypertension also increases the elimination of calcium in urine, potentially leading to loss of bone mineral density, a significant risk factor for fractures, particularly in elderly women. In one study, women with the highest levels of blood pressure lost bone density at nearly twice the rate of those in the lowest range. It is not clear whether this effect occurs in men or in non-Caucasian women.

Sexual dysfunction is more common and more severe in men with hypertension and in smokers than it is in the general population. Many of the drugs that treat hypertension are thought to cause impotence as a side effect. In these cases, it is reversible when the drugs are stopped. More recent evidence suggests, however, that the disease process that causes hypertension is itself the major cause of erectile dysfunction in these men.

Newer anti-hypertensive drugs, including angiotensin-converting enzyme (ACE) inhibitors and angiotensin-receptor blockers (ARBs), are less associated with erectile dysfunction. ARBs, such as losartan (Cozaar), may be particularly effective in restoring erectile function in men with high blood pressure. Sildenafil (Viagra) is successful in achieving erections in almost two-thirds of patients with controlled high blood pressure. Because sildenafil has a shorter half-life and is eliminated more quickly from the body than newer erectile dysfunction drugs, it may be a safer option for men with hypertension. In a 2003 review of safety data, sildenafil did not appear to pose a risk for men who had both high blood pressure and erectile dysfunction.

Severe, sudden high blood pressure in pregnant women is one component of a condition called preeclampsia (commonly called toxemia) that can be very serious for both mother and child. Preeclampsia occurs in up to 10% of all pregnancies, usually in the third trimester of a first pregnancy, and resolves immediately after delivery. Other symptoms and signs of preeclampsia include protein in the urine, severe headaches, and swollen ankles.

This condition may be caused by a failure of the placenta to embed properly in the uterus, which causes it to misconnect with the mother's blood vessels. As a result, the fetus does not receive a sufficient blood supply, and the mother's own blood pressure increases to replace it. The risk for preeclampsia is higher for first births, multiple births, and for very young women (teenagers) and those over age 35. Pre-existing high blood pressure, diabetes, and kidney disease also increase the risk for preeclampsia. There appears to be a genetic component for this condition, so women whose mothers experienced preeclampsia are also at higher risk.

The reduced supply of blood to the placenta can cause low birth weight and eye or brain damage in the fetus. Severe cases of preeclampsia can cause kidney damage, convulsion, and coma in the mother and can be lethal to both mother and child. Evidence also suggests that preeclampsia can lead to increased risks later in life for coronary heart disease and other heart problems.

Women at risk for preeclampsia (particularly those with existing hypertension) may benefit from having an ultrasound of uterine arteries at 20 - 24 weeks of pregnancy, followed (if abnormal) by 24-hour blood pressure monitoring. Blood pressure medications may be required. Delivery is the main cure for preeclampsia. In severe cases, the obstetrician will need to induce pre-term birth.

High blood pressure may increase the risk of developing fibroids, according to data from the Nurses’ Health Study. Tracking women for 10 years, the prospective epidemiologic study found that for every 10 mm/Hg increase in diastolic blood pressure, the risk for developing fibroids increased by 8 - 10%.

Children with high blood pressure should first be treated with lifestyle changes, including weight reduction, increased physical activity, and diet modification. If blood pressure is not controlled with lifestyle changes, drug treatment may be required. Although there are few clinical trials conducted in children, a 2005 study found that the angiotensin receptor blocker losartan was safe and effective in children. Results of studies evaluating outcomes of children with hypertension suggest that early abnormalities, including enlarged heart and abnormalities in the kidney and eyes, may occur even in children with mild hypertension. Children and adolescents with hypertension should be monitored and evaluated for any early organ damage. Secondary hypertension (high blood pressure due to another disease or drug) is more common in children than adults.

Symptoms

Hypertension has aptly been called the "silent killer" because it usually produces no symptoms. Untreated hypertension increases slowly over the years. It is important for anyone with risk factors to have their blood pressure checked regularly and to make appropriate lifestyle changes. Such recommendations are especially important for individuals who have prehypertension or hypertension, a family history of hypertension, are overweight, or are over age 40.

In rare cases (fewer than 1% of all patients with hypertension), the blood pressure rises quickly (with diastolic pressure usually rising to 130 mm Hg or higher), resulting in malignant or accelerated hypertension. This is a life-threatening condition and must be treated immediately. People with uncontrolled hypertension or a history of heart failure are at increased risk for this crisis.

People should call a doctor immediately if these symptoms occur:

Drowsiness
Confusion
Headache
Nausea
Loss of vision

Treatment

Patients with hypertension should work with their doctors to set blood pressure goals based on individual risk factors. Lifestyle and medication programs need to be planned on an individual basis.

Healthy lifestyle changes are imperative for anyone, and are critical for people with even normal blood pressure (120/80 mm Hg) and above. In appropriate patients, aggressive drug treatment of long-term high blood pressure can significantly reduce the incidence of mental decline and death from heart disease and other serious physical effects of hypertension. In people with diabetes, controlling both blood pressure and blood glucose levels prevents serious complications of that disease. Anti-hypertensive drugs may even prevent mental decline, including in people genetically susceptible to Alzheimer's disease. Nevertheless, only slightly over half of patients with hypertension are treated at all, and only a quarter have adequately controlled pressure.

It is not clear when drugs should be started, particularly for people with prehypertension or mild high blood pressure. To help make treatment choices, the U.S. National Heart, Lung, and Blood Institute has created categories (denoted as groups A, B, and C) according to a patient's risk factors for heart disease. Applying these categories to the severity of hypertension helps determine whether lifestyle changes alone or medications are needed.


Risk Groups	Blood Pressure Stages (Systolic/Diastolic)
	Prehypertension (120 - 139/80 - 89)	Mild (Stage 1) Blood Pressure (140 - 159/90 - 99)	Moderate-to-Severe (Stage 2) Blood Pressure (Systolic pressure over 160 or diastolic pressure over 100)
Risk Group A Have no risk factors for heart disease.	Lifestyle changes only. (Exercise and dietary program with regular monitoring.)	Year trial of lifestyle changes only. If blood pressure is not lower at 1 year, add drug treatments.	Lifestyle changes and medications.
Risk Group B Have at least one risk factor for heart disease* (excluding diabetes) but have no target organ damage (such as in the kidneys, eyes, or heart, or existing heart disease).	Lifestyle changes only.	6-month trial of lifestyle changes only. If blood pressure is not lower at 6 months, add drug treatments. Medications considered for patients with multiple risk factors.	Lifestyle changes and medications.
Risk Group C Have diabetes with or without target organ damage and existing heart disease (with or without risk factors for heart disease).	Lifestyle changes and medications.	Lifestyle changes and medications.	Lifestyle changes and medications.

* Risk factors for heart disease include the following: family history of heart disease, smoking, unhealthy cholesterol and lipid levels, diabetes, being over 60 years old.

Lifestyle Changes

Healthy lifestyle changes are an important first step for lowering blood pressure. Current guidelines recommend that people should:

Exercise at least 30 minutes a day
Maintain normal weight
Reduce salt intake
Increase potassium intake
Limit alcohol consumption; however, moderate alcohol consumption (1 – 2 glasses a day) may actually lower the risk for heart attack among men with high blood pressure
Consume a diet rich in fruits, vegetables, and low-fat dairy products while reducing total and saturated fat intake. (The DASH diet is one way of achieving such a dietary plan.)

The DASH diet (Dietary Approaches to Stop Hypertension) is proven to help lower blood pressure. Results are sometimes seen within a few weeks. Restricting sodium improves results. The diet appears to have antioxidant effects and may help lower LDL cholesterol levels, although beneficial HDL levels also decline. This diet is not only rich in important nutrients and fiber but also includes foods that contain far more electrolytes, potassium (4,700 mg/day), calcium (1,250 mg/day), and magnesium (500 mg/day) than are found in the average American diet.

A diet that is effective in lowering blood pressure is called Dietary Approaches to Stop Hypertension (DASH).

DASH diet recommendations:

Limit salt intake to no more than 2,300 mg a day (a maximum intake of 1,500 mg a day is an even better goal).
Reduce saturated fat to no more than 6% of daily calories and total fat to 27% of daily calories. (But, include dairy products that are non- or low-fat. Low-fat dairy products appear to be especially beneficial for lowering systolic blood pressure).
When choosing fats, select monounsaturated oils, such as olive or canola oils.
Choose whole grains over white flour or pasta products.
Choose fresh fruits and vegetables every day. In one study, people who increased their intake of fruits and vegetables experienced a drop in blood pressure after 6 months. Many of these foods are rich in potassium, fiber, or both, possibly helping lower blood pressure.
Include nuts, seeds, or legumes (dried beans or peas) daily.
Choose modest amounts of protein (no more than 18% of total daily calories). Fish, skinless poultry, and soy products are the best protein sources.
Other daily nutrient goals in the DASH diet include limiting carbohydrates to 55% of daily calories and dietary cholesterol to 150 mg. Patients should try to get at least 30 g of daily fiber.

Slight changes to the DASH diet might help further lower blood pressure, as well as improve cholesterol and lipid levels. Researchers reporting in the Journal of the American Medical Association and at the 2005 American Heart Association meeting said that replacing some carbohydrates in the DASH diet with more protein (from plant sources) or monounsaturated fats may help further reduce heart disease risk factors.

A combination of the DASH diet and salt restriction is extremely effective in reducing blood pressure. Reducing sodium may also help protect against heart failure. People with normal blood pressure should consume no more than 2,400 milligrams (about one teaspoon) of sodium each day. People with blood pressure should consume much less. (Patients should consult their doctor on individual recommendations for salt intake.) The following higher-risk groups should take particular measures to restrict salt:

People at Risk for Salt-Sensitivity. About half of people with hypertension have blood pressure that reacts significantly to salt. Such people are known to be salt-sensitive. Groups at particularly high risk for salt-sensitivity include African-Americans, the elderly, and people with diabetes. Even people with normal blood pressure can be salt-sensitive. High-salt diets in anyone who is salt-sensitive may harm the heart, kidneys, and brain and increase the risk for death, regardless of blood pressure. Because testing for salt-sensitivity is not easy, experts recommend that everyone proactively restrict their daily salt-intake.
Overweight People. Overweight individuals may absorb and retain sodium differently from people with normal weights. Reducing sodium can also help lower the risk of heart disease and stroke in people who are overweight. Unfortunately, because overweight people generally consume more calories, they are also likely take in more sodium.
People on Anti-Hypertensive Drugs. Restricting salt also enhances the benefits of many standard anti-hypertensive drugs by reducing potassium loss, and may help protect against kidney disease in patients who are also taking calcium-blocker drugs. A low-salt diet can also increase the chances for being able to stop such medications.

Simply eliminating table and cooking salt can be beneficial. Salt substitutes, such as Cardia, (containing mixtures of potassium, sodium, and magnesium) are available, but they are expensive. In any case, about 75% of the salt in the typical American diet comes from processed or commercial foods, not from food cooked at home, so the benefits of table-salt substitutes are likely to be very modest. Some sodium is essential to protect the heart, but most experts agree that the amount is significantly less than that found in the average American diet. If people cannot significantly reduce the amount of salt in their diets, adding potassium-rich foods might help to restore a healthy balance.

Evidence strongly indicates that a potassium-rich diet can help achieve healthy blood pressure levels, and that potassium supplements can lower systolic blood pressure by 1.8 m Hg and diastolic blood pressure by 1 mm Hg. Some evidence suggests that a potassium-rich diet can reduce the risk of stroke by 22 - 40%. Current expert guidelines support the use of potassium supplements or enough dietary potassium to achieve 3,500 mg per day for people with normal or high blood pressure (who have no risk factors for excess potassium levels). This goal is particularly important in people who have high sodium intake.

The best source of potassium is the fruits and vegetables that contain them. Some potassium-rich foods include bananas, oranges, pears, prunes, cantaloupes, tomatoes, dried peas and beans, nuts, potatoes, and avocados.

Excess potassium can cause abdominal distress, muscle weakness, and, in rare cases, dangerous heart events. Some people should be particularly cautious about excess potassium, including those with conditions, such as diabetes or kidney disease, that increase potassium levels. People who take medications, such as ACE inhibitors or potassium-sparing diuretics that limit the kidney's ability to excrete potassium, should not take potassium supplements.

Smoking. Everyone should quit smoking.

Alcohol. People who drink alcohol should do so in moderation. Men with hypertension should limit their intake to no more than one or two drinks a day, and women and lighter people should drink less.

Caffeine Drinks. Coffee drinking is associated with small increases in blood pressure, but the risk is very small in people with normal blood pressure. People with existing hypertension should avoid caffeine altogether.

Fiber. Fiber supplementation can help reduce blood pressure levels. It may take up to 8 weeks to achieve the maximum benefit.

Folate. Increasing folate (a B vitamin) intake to more than 800 mcg/day can help reduce blood pressure, particularly for younger women (under age 46). Dietary sources of folate include citrus fruits, leafy green vegetables, beans, and grain products. Folate helps to reduce homocysteine levels.

Fish Oil and Omega 3 Fatty Acids. Omega 3 fatty acids (docosahexaenoic and eicosapentaneoic acids) are found in oily fish. Studies indicate that they may have specific benefits for many medical conditions, including hypertension. They appear to help keep blood vessels flexible and may help protect the nervous system. Fatty acids are also available in supplements, but their long-term effects on blood pressure are unknown.

Click the icon to see an image of omega-3 fatty acids

Calcium. Calcium regulates the tone of the smooth muscles lining blood vessels. Studies have found that people who have sufficient dietary calcium have lower blood pressure than those who do not. Hypertension itself increases calcium loss from the body. The effects of extra calcium on blood pressure, however, are mixed, with some even showing higher pressure.

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

Magnesium. Some studies reported that magnesium supplements may induce small but significant reductions in blood pressure. No major studies, however, have been done on long-term benefits or risks of magnesium supplements. A major 2001 study on diet found no effect on blood pressure from magnesium intake from foods.

Antioxidant Supplements. Antioxidants are substances that help the body eliminate oxidants, (also called oxygen-free radicals), which are damaging particles produced as part of the body's chemical processes. Some antioxidant supplements, including vitamins C and E and alpha-lipoic acid, are being studied for possible benefits in protecting against hypertension by preventing injury in the blood vessels. Vitamin C may have specific benefits for hypertension by preventing dangerous effects on nitric acid, the substance that keeps arteries flexible.

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

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

In people who are overweight, even modest reductions in weight, particularly in the abdominal area, can immediately reduce blood pressure. Weight loss, particularly accompanied by salt restriction, may allow patients with mild hypertension, even older people, to safely reduce or go off medications. The benefits of weight loss on blood pressure are long-lasting.

Positive Effects on Blood Pressure. Regular exercise helps keep arteries elastic, even in older people, which in turn ensures blood flow and normal blood pressure. Sedentary people have a 35% greater risk of developing hypertension than athletes.

Experts recommend at least 30 minutes of exercise on most -- if not all-days. In one study, moderate exercise (jogging two miles per day) controlled hypertension so well that more than half the patients who had been taking drugs for high blood pressure were able to discontinue their medication.

Studies have also indicated that yoga and Tai Chi, an ancient Chinese exercise involving slow, relaxing movements, may lower blood pressure almost as well as moderate-intensity aerobic exercises.

High-intensity exercise may not lower blood pressure as effectively as moderate intensity exercise and may be dangerous in people with hypertension.

Negative Effects. Each year an estimated 75,000 heart attacks (5% of all heart attacks) occur after heavy exertion, leading to 25,000 deaths. Older people and those with uncontrolled hypertension or other serious medical conditions should be cautious when exercising. Studies report that older people who begin vigorous exercise are at a slightly higher than average risk for a heart attack during the first year, but over time, regular exercise is likely to be protective.

The following activities may pose particular dangers for high-risk individuals:

Intense workouts (snow shoveling, slow jogging, speed walking, tennis, heavy lifting, heavy gardening). They tend to stress the heart, raise blood pressure for a brief period, and may cause spasms in the arteries leading to the heart.
Competitive sports, which couple intense activity with aggressive emotions.

Effects of Anti-Hypertensive Drugs on Exercise. Certain anti-hypertensive medications, including diuretics and beta-blockers, can interfere with exercise capacity. ACE inhibitors or calcium-channel blockers are the best drugs for active individuals. However, patients who take drugs that interfere somewhat with exercise capability should still adhere to an exercise program and consult a doctor on how best to balance medications with exercise.

Click the icon to see an image about lifestyle changes for hypertension.

Certain sleep disorders, especially sleep apnea, are associated with hypertension. Even chronic, insufficient sleep may raise blood pressure in patients with hypertension, placing them at increased risk of heart disease and death. Stress hormone levels increase with sleeplessness, which can activate the sympathetic nervous system, a strong player in hypertension. Patients who have chronic insomnia or other severe sleep disturbances, (particularly sleep apnea), may want to consult a sleep expert. Patients with hypertension who are habitually poor sleepers should consider long-acting blood pressure medications to help counteract the increase in blood pressure that occurs in the early morning hours.

Improving mood or relieving stress may be helpful. The following studies suggested possible benefits:

Stress reduction programs that use cognitive-behavioral therapy may reduce blood pressure.
Active religious faith was associated with healthy blood pressure levels, possibly indicating the combined benefits of a strong social network and reduced stress from spiritual activities.
A simple relaxation technique called transcendental meditation (TM), which involves silent repetition of a single sound, was associated with lower blood pressure.

Treating stress cannot cure medical problems. Stress management programs are not a substitute for standard medical treatments, but can be a very important component of a lifestyle plan.

Medications

Dozens of anti-hypertensive drugs are available. Most fall into the following categories:

Diuretics rid the body of extra water and salt. Diuretics are usually the first-line treatment for high blood pressure.
Beta-blockers block the effects of adrenaline and ease the heart's pumping action.
Angiotensin converting enzyme (ACE) inhibitorsreduce the production of angiotensin, a chemical that causes arteries to narrow.
Calcium-channel blockers (CCBs) decrease the contractions of the heart and widen blood vessels.
Angiotensin-receptor blockers (ARBs) block angiotensin, another chemical that constricts the arteries.
Vasodilators expand blood vessels.

In about half of patients a single-drug regimen can control mild to moderate hypertension. More severe hypertension often requires a combination of two or more drugs. Each drug has specific benefits, but their effects may vary depending on the individual patient.

One of the most difficult issues that patients face, particularly those with primary hypertension, is that the treatment may make them feel worse than the disease, which usually has no symptoms. Whatever the difficulties, compliance with a drug and lifestyle program is worth the effort. It is very important that patients discuss medication concerns with their doctors. If current blood pressure drugs are causing uncomfortable side effects, the doctor may adjust dosages or combinations.

Patients whose blood pressure has been well-controlled and who are able to maintain a healthy life style may choose to withdraw from medications. They should do so in a step-down manner (gradual reduction) and be monitored regularly. Stopping too quickly can have adverse effects, including serious effects on the heart. The highest success rates are more likely in those who lose weight and reduce sodium intake, in patients who have been treated with a single drug, and in those who have maintained lower systolic blood pressure during treatment. People over 75 years old may have more trouble than younger adults in maintaining normal blood pressure after withdrawal.

Classes of Medications

There are several classes of drugs used to treat hypertension.

Diuretics help the kidneys get rid of excess salt and water. They are the mainstays of anti-hypertensive therapy and are the first drug of choice for most people with hypertension. They are especially helpful for treating the elderly and African-American patients. (African-Americans are more likely to be salt-sensitive, so they respond well to these drugs.) They also work well for patients with diabetes.

Results from the long-term Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), published in the Journal of the American Medical Association in 2005, confirm that thiazide-type diuretics should be the first treatment option for most patients with hypertension. The landmark trial included over 33,000 patients (35% black) with hypertension and at least one other cardiovascular risk factor. Patients were randomized to receive a calcium channel blocker, an ACE inhibitor, or a thiazide-type diuretic.

Results suggested that the diuretic worked just as well as the newer drugs in lowering blood pressure and was more effective in preventing heart failure, heart attack, and stroke. The benefits for the diuretic were even more significant for African-American patients. Other trial results indicated that patients taking the calcium channel blocker had the greatest risk for heart failure, and that the ACE inhibitor was much less effective than the diuretic in lowering blood pressure and preventing stroke in African-American patients.

Diuretic Types and Brands. There are many brands of diuretics. They are generally inexpensive. Some need to be taken once a day, some twice a day. Low doses are usually as effective for lowering blood pressure as higher doses. Diuretics are usually used in combination with other drugs, especially ACE inhibitors and beta blockers.

There are three main types of diuretics:

Potassium-sparing diuretics. These include amiloride (Midamor), spironolactone (Aldactone), and triamterene (Dyrenium).
Thiazide diuretics. These include chlorothiazide (Diuril), chlorthalidone (Hygroton), indapamide (Lozol), hydrochlorothiazide (Esidrix, HydroDiuril), and metolazone (Mykrox, Zaroxolyn).
Loop diuretics. Because loop diuretics act faster than other diuretics it is important to avoid dehydration and potassium loss. Loop diuretics include bumetanide (Bumex), furosemide (Lasix), and torsemide (Demadex).

Benefits of Diuretics. Diuretics can:

Reduce the risk for stroke
Reduce the risk for heart attack and heart failure
Protect against blood clots.

Problems with Diuretics. Loop and thiazide diuretics reduce the body's supply of potassium, which, if left untreated, increases the risk for arrhythmias. Arrhythmias are heart rhythm disturbances that can, in rare instances, lead to cardiac arrest. In such cases, doctors will prescribe lower doses of the current diuretic, recommend potassium supplements, or use potassium-sparing diuretics either alone or in combination with a thiazide. Potassium-sparing drugs have their own risks, which include dangerously high levels of potassium in people with existing elevated levels of potassium or in those with damaged kidneys. However, all diuretics are generally more beneficial than harmful.

Common Diuretic Side Effects:

Fatigue
Depression and irritability
Urinary incontinence
Reduced sexual drive

Beta-blockers help slow heart rate and lower blood pressure. They are usually used in combination with other drugs such as ACE inhibitors and diuretics.

Brands. Propranolol (Inderal), acebutolol (Sectral), atenolol (Tenormin), betaxolol (Kerlone), carteolol (Cartrol), metoprolol (Lopressor), nadolol (Corgard), penbutolol (Levatol), pindolol (Visken), carvedilol (Coreg), and timolol (Blocadren). The drugs may differ in their effects and benefits.

Problems with Beta-Blockers. Evidence presented at the 2005 meeting of the American College of Cardiology suggested that an ACE-inhibitor combined with a calcium channel blocker works just as well as a beta-blocker-diuretic combination in treating hypertension, and poses less risk of diabetes. Other recent studies suggest that beta-blockers may increase the risk of stroke, and should not be a first-line choice for high blood pressure treatment.

Do not abruptly stop taking these drugs. The sudden withdrawal of beta blockers can rapidly increase heart rate and blood pressure. The doctor may want the patient to slowly decrease the dose before stopping completely.
Beta blockers are categorized as non-selective or selective. Non-selective beta blockers such as carvedilol and propranolol may sometimes narrow bronchial airways. These beta blockers should not be used by patients with asthma, emphysema, or chronic bronchitis.
Beta blockers can lower HDL (“good”) cholesterol.
These drugs can hide warning signs of low blood sugar (hypoglycemia) in patients with diabetes. When combined with a diuretic, the risk of diabetes may be increased.

Common Side Effects

Fatigue and lethargy
Vivid dreams and nightmares
Depression
Memory loss
Dizziness and lightheadedness
Reduced ability to exercise
Coldness in extremities (legs, toes, arms, hands)

Check with your doctor about any side effects. Do not stop taking these drugs on your own..

Angiotensin-converting enzyme (ACE) inhibitors open blood vessels and decrease the workload of the heart. They are used to treat high blood pressure but can also help improve heart and lung muscle function.

These drugs are particularly important for patients with diabetes. A large study reported that patients with diabetes who took these drugs had fewer heart attacks and lower overall mortality rates than patients who took other types of high blood pressure medications. ACE inhibitors may also help slow progression of kidney disease, in addition to controlling blood pressure. They may also be better at preventing the development of diabetes in patients with kidney disease than other types of blood pressure medication. In a 2006 study of African-American patients with high blood pressure and kidney disease, patients who took an ACE inhibitor had a lower risk of developing diabetes than those who took a calcium channel blocker or beta-blocker drug.

Doctors sometimes avoid giving aspirin to patients who are taking ACE inhibitors due to concerns that this drug combination can cause kidney problems. A 2005 study of patients with both coronary artery disease and heart failure indicated that an aspirin and ACE inhibitor combination is not harmful, and that aspirin can significantly reduce mortality risk for these patients.

Brands. ACE inhibitors include captopril (Capoten), enalapril (Vasotec), quinapril (Accupril), benazepril (Lotensin), ramipril (Altace), perindopril (Aceon), and lisinopril (Prinivil, Zestril).

Common Side Effects of ACE Inhibitors:

Low blood pressure is the main side effect of ACE inhibitors. This can be severe in some patients, especially at the start of therapy.
Irritating cough is a common side effect, which some people find intolerable. Although all ACE inhibitors can have this side effect, sometimes switching to another brand will reduce this symptom.
ACE inhibitors can harm a developing fetus and should not be used during pregnancy. While it has long been known that these drugs can cause problems in the second and third trimester, an important 2006 study indicated that ACE inhibitors can also cause major heart birth defects when taken during the first trimester. The FDA and the American Heart Association recommend that women who become pregnant should change from ACE inhibitors to another type of blood pressure drug as soon as possible. Women of child-bearing age who are considering becoming pregnant should also discuss alternative drugs with their doctors.

Uncommon Side Effects of ACE Inhibitors:

ACE inhibitors protect against kidney disease, but they may also increase potassium retention by the kidneys. If potassium levels become extremely high, they can cause the heart to stop beating (cardiac arrest). This side effect is rare, except in patients with significant kidney disease. Because of this risk, ACE inhibitors are not usually used in combination with potassium-sparing diuretics or potassium supplements.
A rare but severe side effect is granulocytopenia, an extreme reduction in infection-fighting white blood cells.
In very rare cases, patients suffer a sudden and severe allergic reaction, called angioedema that causes swelling in the eyes and mouth and may close off the throat.

Patients who have difficulty tolerating ACE inhibitor side effects are usually switched to an angiotensin-receptor blocker (ARB).

ARBs, also known as angiotensin II receptor antagonists, are similar to ACE inhibitors in their ability to open blood vessels and lower blood pressure. They may have fewer or less-severe side effects than ACE inhibitors, especially coughing, and are sometimes prescribed as an alternative to ACE inhibitors. ARBs are particularly important drugs for patients with diabetes. They may help protect against kidney disease and kidney failure.

A 2006 study in the New England Journal of Medicine suggested that some patients with prehypertension may benefit from treatment with an ARB drug. Patients in the study received candesartan (Atacand).

Brands. Losartan (Cozaar, Hyzaar), olmesartan (Benicar) candesartan (Atacand), telmisartan (Micardis), eprosartan (Teveten), irbesartan (Avapro), and valsartan (Diovan). A combination medication containing candesartan and the diuretic hydrochlorothiazide (Diovan HCT, Atacand HCT) is also available.

Side Effects:

Low blood pressure
Dizziness and lightheadedness
Raised potassium levels
Drowsiness
Nasal congestion
Should not be used during pregnancy

Calcium-channel blockers (CCBs), or calcium antagonists, help relax blood vessels. Along with diuretics, CCBs may work better than other drug classes for lowering blood pressure in African-Americans. Recent research indicates that newer types of drugs (CCBs, ACE inhibitors) may be a better treatment option for some patients than older drugs (especially beta blockers).

Brands. Diltiazem (Cardizem, Dilacor), amlodipine (Norvasc), felodipine (Plendil), isradipine (DynaCirc), verapamil (Calan, Isoptin, Verelan), nisoldipine (Sular), nicardipine (Cardene), nifedipine (Adalat, Procardia), lercanidipine (Zanidip), lacidipine (Motens), and nitrendipine (Nitrepin). In 2004, a dual-therapy calcium channel blocker-statin combination drug (Caduet) was approved to treat high blood pressure and high cholesterol. Caduet is a fixed-dose combination of amlodipine and atorvastatin.

Side Effects:

Swelling in the feet
Constipation
Fatigue
Erectile dysfunction
Gingivitis
Rash
Food interactions (do not take CCBs with grapefruit or Seville orange products)

Alpha blockers such as doxazosin (Cardura), prazosin (Minipress), and terazosin (Hytrin) help widen small blood vessels. They are generally not used as first-line drugs for high blood pressure, but are prescribed if other drugs do not work or as add-on medication.

Vasodilators, which help open blood vessels by relaxing muscles in the blood vessel walls. These drugs are usually used in combination with a diuretic or a beta-blocker. They are rarely used by themselves. Vasodilators include hydralazine (Apresoline), clonidine (Catapres), available in tablets or as a skin patch), and Minoxidil (Loniten). Some of these drugs should be used with caution or not at all in people who have angina or who have had a heart attack.

Aliskiren (Tekturna). In 2007, the FDA approved aliskiren for treatment of high blood pressure. Aliskiren can be taken either alone or in combination with other blood pressure medication. It should not be used during pregnancy as it can cause injury or death to the fetus. Aliskiren is the first hypertension drug that inhibits renin, a kidney enzyme that is associated with the regulation of blood pressure.

Statins. Statins, common drugs used to lower cholesterol, are proving to have many other health benefits. They include lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), fluvastatin (Lescol), atorvastatin (Lipitor), and rosuvastatin (Crestor). In an important 2002 study, patients with high blood pressure but normal or slightly high cholesterol levels had fewer heart attacks and strokes when they took the a statin drug. In 2004, a calcium channel blocker-statin combination drug (Caduet) was approved to treat simultaneously high blood pressure and high cholesterol. Caduet is a fixed-dose combination of amlodipine and atorvastatin.

Resources

www.acc.org -- American College of Cardiology
www.americanheart.org -- American Heart Association
www.ash-us.org -- American Society of Hypertension
www.nhlbi.nih.gov/hbp -- National Heart, Lung, and Blood Institute
www.nhlbi.nih.gov/health/public/heart/hbp/dash -- DASH diet
www.ishib.org -- International Society on Hypertension in Blacks
www.eatright.org -- American Dietetic Association

References

Barzilay JI, Davis BR, Cutler JA, Pressel SL, Whelton PK, Basile J, et al. Fasting glucose levels and incident diabetes mellitus in older nondiabetic adults randomized to receive 3 different classes of antihypertensive treatment: a report from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). Arch Intern Med. 2006 Nov 13;166(20):2191-201.

Beulens JW, Rimm EB, Ascherio A, Spiegelman D, Hendriks HF, Mukamal KJ. Alcohol consumption and risk for coronary heart disease among men with hypertension. Ann Intern Med. 2007 Jan 2;146(1):10-9.

Cooper WO, Hernandez-Diaz S, Arbogast PG, Dudley JA, Dyer S, Gideon PS, et al. Major congenital malformations after first-trimester exposure to ACE inhibitors. N Engl J Med. 2006 Jun 8;354(23):2443-51.

Davis BR, Piller LB, Cutler JA, Furberg C, Dunn K, Franklin S, et al. Role of diuretics in the prevention of heart failure: the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial. Circulation. 2006 May 9;113(18):2201-10.

Djousse L, Pankow JS, Hunt SC, Heiss G, Province MA, Kabagambe EK, et al. Influence of saturated fat and linolenic acid on the association between intake of dairy products and blood pressure. Hypertension. 2006 Aug;48(2):335-41.

Forman JP, Rimm EB, Curhan GC. Frequency of analgesic use and risk of hypertension among men. Arch Intern Med. 2007 Feb 26;167(4):394-9.

Peila R, White LR, Masaki K, Petrovitch H, Launer LJ. Reducing the risk of dementia: efficacy of long-term treatment of hypertension. Stroke. 2006 May;37(5):1165-70.

Taylor EN, Hu FB, Curhan GC. Antihypertensive medications and the risk of incident type 2 diabetes. Diabetes Care. 2006 May;29(5):1065-70.

Thornley-Brown D, Wang X, Wright JT Jr, Randall OS, Miller ER, Lash JP, et al. Differing effects of antihypertensive drugs on the incidence of diabetes mellitus among patients with hypertensive kidney disease. Arch Intern Med. 2006 Apr 10;166(7):797-805.

Review Date:
4/12/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Heart failure

FitSugar — Wed, 08 Oct 2008 17:35:10 -0700

In This Report

Highlights
Introduction
Causes
Symptoms
Risk Factors
Complications
Diagnosis
Treatment
Medications
Surgery and Devices
Lifestyle Changes
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Permanent Implantable Heart Approved

In 2006, the FDA approved the first permanent artificial heart. The AbiCor is intended for patients who are not eligible for heart transplants and who are only expected to survive about a month without medical treatment. Patients who received the AbiCor have survived, on average, about 5 months.

Statin Drug Approved for Heart Failure

In 2006, the FDA approved the cholesterol drug atorvastatin (Lipitor) to reduce the risks of hospitalization for heart failure in patients with heart disease.

Drug Research

The investigational drug tolvaptan improved symptoms in patients hospitalized with severe heart failure and fluid build-up in the lungs, according to several 2007 Journal of the American Medical Association (JAMA) studies. However, the drug did not reduce the risks of re-hospitalization and death.

Preserved Versus Reduced Ejection Fraction

Heart failure with preserved left-ventricular ejection fraction (LVEF) is becoming more common, suggests several 2006 studies published in JAMA and the New England Journal of Medicine. Unfortunately, this type of heart failure is less well studied than reduced LVEF. Experts are urging that more studies be conducted to determine better treatment options for preserved LVEF. Both types of heart failure have high mortality rates.

Systolic Blood Pressure Predictor of Mortality

Patients who are admitted to the hospital with heart failure and low systolic blood pressure have a poorer chance of survival than patients admitted with high blood pressure, indicates a 2006 JAMA study.

Diet and Lifestyle Factors

Daily consumption of whole-grain breakfast cereals may reduce the risk for heart failure, suggests research presented at a 2007 American Heart Association conference on heart disease prevention.
A drink or two a day is associated with lower risk of heart failure, indicates a 2006 Journal of the American College of Cardiology study. However, heavy alcohol consumption can increase the risk for heart failure.

Introduction

To understand what occurs in heart failure, it is useful to be familiar with the anatomy of the heart and how it works. The heart is composed of two independent pumping systems, one on the right side, and the other on the left. Each has two chambers, an atrium and a ventricle. The ventricles are the major pumps in the heart.

The external structures of the heart include the ventricles, atria, arteries, and veins. Arteries carry blood away from the heart while veins carry blood into the heart. The vessels colored blue indicate the transport of blood with relatively low content of oxygen and high content of carbon dioxide. The vessels colored red indicate the transport of blood with relatively high content of oxygen and low content of carbon dioxide.

The Right Side of the Heart. The right system receives blood from the veins of the whole body. This is "used" blood, which is poor in oxygen and rich in carbon dioxide.

The right atrium is the first chamber that receives blood.
The chamber expands as its muscles relax to fill with blood that has returned from the body.
The blood enters a second muscular chamber called the right ventricle.
The right ventricle is one of the heart's two major pumps. Its function is to pump the blood into the lungs.
The lungs restore oxygen to the blood and exchange it with carbon dioxide, which is exhaled.

The Left Side of the Heart. The left system receives blood from the lungs. This blood is now oxygen rich.

The oxygen-rich blood returns through veins coming from the lungs (pulmonary veins) to the heart.
It is received from the lungs in the left atrium, the first chamber on the left side.
Here, it moves to the left ventricle, a powerful muscular chamber that pumps the blood back out to the body.
The left ventricle is the strongest of the heart's pumps. Its thicker muscles need to perform contractions powerful enough to force the blood to all parts of the body.
This strong contraction produces systolic blood pressure (the first and higher number in blood pressure measurement). The lower number ( diastolic blood pressure) is measured when the left ventricle relaxes to refill with blood between beats.
Blood leaves the heart through the ascending aorta, the major artery that feeds blood to the entire body.

The Valves. Valves are muscular flaps that open and close so blood will flow in the right direction. There are four valves in the heart:

The tricuspid regulates blood flow between the right atrium and the right ventricle.
The pulmonary valve opens to allow blood to flow from the right ventricle to the lungs.
The mitral valve regulates blood flow between the left atrium and the left ventricle.
The aortic valve allows blood to flow from the left ventricle to the ascending aorta.

Click the icon to see an image of the internal structures of the heart.

The Heart's Electrical System. The heartbeats are triggered and regulated by the conducting system, a network of specialized muscle cells that form an independent electrical system in the heart muscles. These cells are connected by channels that pass chemically caused electrical impulses.

Click the icon to see an image of the conduction system of the heart.

Heart failure is not a disease. It is a condition or process in which the heart is unable to pump enough blood to meet the needs of the body's tissues. The heart doesn't "fail" in the sense of ceasing to beat (as occurs during a heart attack). Rather, it weakens, usually over the course of months or years, so that it is unable to pump out all the blood that enters its chambers. As a result, fluids tend to build up in the lungs and tissues, causing congestion. This condition used to be called "congestive heart failure," but the name was officially changed to heart failure in 2005.

Ways the Heart Can Fail. Heart failure can occur in several ways:

The muscles of the heart pumps (ventricles) become thin and weakened. They stretch (dilate) to the extent that they cannot pump the blood with enough force to reach all the body's tissues.
The heart muscles stiffen or thicken. Here, they lose elasticity and cannot relax. Insufficient blood enters the chamber, so not enough blood is pumped out into the body to serve its needs.
Sometimes the valves of the heart are abnormal. (Valves open or close to control the flow of blood entering or leaving the heart). They may narrow, such as in aortic stenosis, causing a back up of blood, or they may close improperly so that blood leaks back into the heart. The mitral valve (which regulates blood flow between the two chambers on the left side of the heart) often becomes leaky in severe heart failure -- a condition called mitral regurgitation.

Click the icon to see an image of the valves of the heart.

The very mechanisms that the body uses to compensate for inefficient heart pumping can, over time, change the architecture of the heart (called remodeling) and finally lead to irreversible problems.

The specific effects of heart failure on the body depend on whether it occurs on the left or right side. Over time, however, in either form of heart failure, the organs in the body do not receive enough oxygen and nutrients, and the body's wastes are removed slowly. Eventually, vital systems break down.

Failure on the Left Side (Left-Ventricular Heart Failure). Failure on the left side of the heart is more common than failure on the right side. The failure can be a result of abnormal systolic (contraction) or diastolic (relaxation) action:

Systolic. Systolic heart failure is a pumping problem. In systolic failure, the heart muscles weaken and cannot pump enough blood throughout the body. The left ventricle is usually stretched (dilated). Fluid backs up and accumulates in the lungs (pulmonary edema). Systolic heart failure typically occurs in men between the ages of 50 - 70 years who have had a heart attack.
Diastolic. Diastolic heart failure is a filling problem. When the left ventricle muscle becomes stiff and cannot relax properly between heartbeats, the heart cannot fill fully with blood. When this happens, fluid entering the heart backs up. This causes the veins in the body and tissues surrounding the heart to swell and become congested. Patients with diastolic failure are typically women, overweight, and elderly, and have high blood pressure and diabetes.

Failure on the Right Side (Right-Ventricular Heart Failure). Failure on the right side of the heart is most often a result of failure on the left. Because the right ventricle receives blood from the veins, failure here causes the blood to back up. As a result, the veins in the body and tissues surrounding the heart to swell. This causes swelling in the feet, ankles, legs, and abdomen.

Ejection Fraction. To help determine the severity of left-sided heart failure, doctors use an ejection fraction (EF) calculation, also called a left-ventricular ejection fraction (LVEF). This is the percentage of the blood pumped out from the left ventricle during each heartbeat. An ejection fraction of 50 - 75% is considered normal. Patients with left-ventricular heart failure are classified as either having a preserved ejection fraction (greater than 50%) or a reduced ejection fraction (less than 50%).

In general, systolic heart failure has been thought to be associated with a reduced ejection fraction, whereas diastolic heart failure was associated with a preserved (normal) ejection fraction. However, several 2006 studies indicated that diastolic heart failure can occur regardless of the ejection fraction, although it is more common in patients with a preserved ejection fraction. Mortality rates among patients with reduced LVEF and preserved LVEF are similar.

Although reduced LVEF heart failure is better studied, and its treatment goals more clearly defined, several important 2006 studies suggest that preserved LVEF heart failure is becoming increasingly common. The studies, published in the Journal of the American Medical Association and the New England Journal of Medicine, indicated that patients with preserved LVEF heart failure are more likely to be female and older, and have a history of high blood pressure and atrial fibrillation (a disturbance in heart rhythm). Experts are now urging that more studies focus on patients with preserved LVEF so that better treatment options can be established.

Causes

Heart failure has many causes and can evolve in different ways.

It can be a direct, last-stage result of heart damage from one or more of several heart or circulation diseases.
It can occur over time as the heart tries to compensate for abnormalities caused by these conditions, a condition called remodeling.

In all cases, the weaker pumping action of the heart means that less blood is sent to the kidneys. The kidneys respond by retaining water and salt. This in turn increases edema (fluid buildup) in the body, which causes widespread damage.

Uncontrolled high blood pressure (hypertension) is also a major cause of heart failure even in the absence of a heart attack. In fact, about 75% of cases of heart failure start with hypertension. It generally develops as follows:

The heart muscles thicken to make up for increased blood pressure.
The force of the heart muscle contractions weaken over time, and the muscles have difficulty relaxing. This prevents the normal filling of the heart with blood.

[See In-Depth Report #14:High blood pressure.]

Hypertension is a disorder characterized by consistently high blood pressure. Generally, high blood pressure consists of systolic blood pressure (the "top" number, which represents the pressure generated when the heart beats) higher than 140, or diastolic blood pressure (the "bottom" number, which represents the pressure in the vessels when the heart is at rest) over 90.

Coronary artery disease is the end result of a complex process called atherosclerosis (commonly called "hardening of the arteries"). It is the most common cause of heart attack and involves the build-up of unhealthy cholesterol in the arteries, with inflammation and injury in the cells of the blood vessels. The arteries narrow and become brittle. Heart failure in such cases most often results from a pumping defect in the left side of the heart. [See In-Depth Report #3: Coronary artery disease and angina ; and In-Depth Report #23: Cholesterol.]

Click the icon to see an image of atherosclerosis.

People now often survive heart attacks, but eventually many develop heart failure from the physical damage done to the heart muscles by the attack. Ironically, heart attack recovery is probably one of the major factors in the dramatic increase in heart failure cases over the past decade. On an encouraging note, however, new therapies that are reducing the severity of heart attacks may help stabilize heart failure rates. [See In-Depth Report #12: Heart attack.]

The valves of the heart control the flow of blood leaving and entering the heart. Abnormalities can cause blood to back up or leak back into the heart.

Click the icon to see an image of the heart valves.

In the past, rheumatic fever, which scars the heart valves and prevents them from closing, was a major cause of death from heart failure. Fortunately, antibiotics have relegated this disease to a minor cause of heart failure. Birth defects may also cause abnormal valvular development. Although more children born with heart defects are now living to adulthood, they still face a higher than average risk for heart failure as they age.

Cardiomyopathy is disease that damages the heart muscles and leads to heart failure. There are several different types. Injury to the heart muscles may cause the heart muscles to thin out (dilate) or become too thick (become hypertrophic). In either case, the heart doesn't pump correctly.

Dilated Cardiomyopathy. Dilated cardiomyopathy involves an enlarged heart ventricle. The muscles thin out, reducing the pumping action, usually on the left side. Although this condition is associated with genetic factors, the direct cause often is not known. (This is called idiopathic dilated cardiomyopathy.) Research strongly indicates that viruses, such as Coxsackie virus, or other infections may be at the base of this condition. Experts think that an autoimmune response occurs in which infection-fighting antibodies attack a person's own proteins in the heart, mistaking them for foreign substances.

Click the icon to see an image of dilated cardiomyopathy.

Hypertrophic Cardiomyopathy. In hypertrophic cardiomyopathy, the heart muscles become thick and contract with difficulty. Some research indicates that this occurs because of a genetic defect that causes a loss of power in heart muscle cells and, subsequently, lower pumping strength. To compensate for this power loss, the heart muscle cells grow. This condition, rare in the general population, is often the cause of sudden death in young athletes.

Click the icon to see an image of hypertrophic cardiomyopathy.

High blood pressure, heart attacks, or other initial processes that impair the pumping actions of the heart trigger a number of hormonal and neurochemical mechanisms to correct imbalances in pressure and blood flow. Unfortunately, while these corrective responses help in the short term, they increase the work of the heart. The mechanisms are now viewed as major contributors to the end stages of heart failure. Some are described briefly in the following sections.

Remodeling. The heart responds to high blood pressure and overload by enlarging in order to increase blood input. This leads to structural damage called remodeling:

In order to accommodate the increased blood input, the heart muscle cells elongate. The muscular walls of the heart that they form become thinner and inefficient.
The muscle cells undergo other changes that result in calcium loss. Calcium is a mineral that is crucial for healthy heart contractions.
The thinner heart muscles and the impaired heart contractions further weaken the heart's pump.
Mitral valve regurgitation is a possible outcome of remodeling. The mitral valve regulates blood flow between the two chambers on the left side of the heart. In response to remodeling, the structural changes in the heart may distort the mitral valve so that the blood leaks backward into the left atrium of the heart instead of flowing out into the body's circulation.
These changes are generally irreversible, although heart pacemakers and certain drugs, including beta-blockers and ACE inhibitors, may reverse some of the remodeling in some patients.

Activation of the Sympathetic Nervous System. The sympathetic nervous system consists of the nerve cells that automatically govern and regulate the beating heart.

This nervous system responds to the failing heart pump by signaling the release of stress hormones, in particular a powerful one called norepinephrine.
These hormones flood the heart, causing it to beat even faster.
These rapid heart beats, although intended to accommodate the weakened pumping actions, only accelerate the damage.

The Renin-Angiotensin-Aldosterone System (RAAS). The renin-angiotensin-aldosterone system (RAAS) is a group of hormones that are responsible for the opening and narrowing of blood vessels and retention of fluids. They also affect cell development in the heart.

The RAAS hormones are called into action by the failing heart.
They respond to the lower blood volume of the weakened heart by constricting the blood vessels and retaining fluids and sodium.
The heart then works harder to pump blood through these narrowed vessels. Blood pressure, then, is forced to increase, which creates a vicious cycle.

Immune System Response. The immune system may also compound the damage. In response to injury in the heart muscle cells or in other parts of the body that occurs as the heart fails, the immune system releases factors intended to protect these areas.

In excess, however, they can cause inflammation and damage.

The most important of these factors are called cytokines. Active cytokines include tumor necrosis factor (TNF) and possibly interleukins 1 and 6.
High levels of these cytokines have been observed in patients with the most severe classes of heart failure.
They may play an important role in the process leading to remodeling. High levels of these cytokines may actually trigger muscle cell growth and enlargement of the heart.

Other Players. Other molecules or compounds have been identified that might play a positive or negative role in the process of the failing heart.

Natriuretic peptides are a family of compounds released to counterbalance the effects of RAAS. Atrial natriuretic peptide (ANP) is a specific member of this family that opens blood vessels and counteracts the sodium-retaining properties of aldosterone (one of the RAAS hormones). It is of particular interest to researchers looking for new treatments.
Endothelin is a powerful protein involved in blood vessel constriction, cell proliferation and build-up, and other negative effects on the heart.
Nitric oxide is important for blood vessel dilation and elasticity.

Symptoms

Many symptoms of heart failure result from the congestion that develops as fluid backs up into the lungs and leaks into the tissues. Other symptoms result from inadequate delivery of oxygen-rich blood to the body's tissues. Since heart failure can progress rapidly, it is essential to consult a doctor immediately if any of the following symptoms are detected.

Fatigue and shortness of breath (dyspnea) are the first symptoms. They are caused by fluid in the lungs. Patients typically report that they feel out of breath after mild exertion. It is unlike the breathlessness of angina, which feels like a heavy weight pressing on the chest.

Fluid retention. Patients may complain of leg or abdominal swelling.
Wheezing or cough. Patients may have asthma-like wheezing or a dry hacking cough that occurs a few hours after lying down, but then stops after the patient sits up.
Central sleep apnea. This disorder results when the brain fails to signal the muscles to breathe during sleep. It occurs in up to half of people with heart failure. Sleep apnea causes disordered breathing at night. If heart failure progresses, the apnea may be so acute that a person, unable to breathe, may awaken from sleep in panic.
Loss of muscle mass. Over time, patients may lose muscle weight due to low cardiac output.

Ultimately, fluid in the lungs may build up. This is called pulmonary edema. When this happens, symptoms become more severe.

In addition to shortness of breath, patients sometimes have a cough that produces a pinkish froth.
Patients may experience a bubbling sensation in the lungs and feel as if they are drowning.
Typically, the skin is clammy and pale, sometimes nearly blue. This is a life-threatening situation, and the patient must go immediately to an emergency room.

Fatigue. As with left-side heart failure, an early symptom of right-side (right-ventricular) failure is extreme tiredness.
Fluid accumulation. This first occurs in the feet, then the ankles and legs, and finally in the abdomen. The liver may also be enlarged.
Weight gain. Although appetites are often depressed, patients with heart failure gain weight because they retain salt and water.
Loss of muscle mass.

Risk Factors

Nearly 5 million Americans currently suffer from heart failure. About 550,000 new cases of heart failure are now diagnosed each year. In 1970 there were only 250,000 new cases, so the annual numbers have risen dramatically. Such numbers represent an increasingly older population. Although there has been a dramatic increase over the last several decades in the number of people who suffer from heart failure, survival rates have been improving greatly.

Coronary artery disease and high blood pressure are the main causes of heart failure. Other diseases that damage or weaken the heart muscle or heart valves can also cause heart failure. Heart failure is most common in people over age 65, African-Americans, and women.

Heart failure is the most common reason for hospitalization in the elderly, and as the population ages, the incidence of heart failure is rising dramatically. According to one report, it occurs at a rate of about 10 in 1,000 people after age 65. The positive implication is, however, that people are living longer with heart failure.

Men are at higher risk for heart failure than women, although the difference narrows with age. Women also have a better survival rate than men do when heart failure is caused by valvular heart disease, high blood pressure, or alcohol abuse. (Some studies indicate that this is because men may be more susceptible to the process of heart muscle-cell remodeling, a damaging effect of hypertension.)

The survival rates of women and men are more similar, however, when heart failure evolves from coronary artery disease or heart attack. Women are much more likely to develop heart failure after a heart attack than men. In such cases, some evidence suggests that the reasons for this may include less aggressive approach to treatment for the initial heart conditions.

African-Americans are at higher risk for heart failure than Caucasians, and studies have reported that they tend to do much worse. In a 2003 study, however, in which Caucasians and African-Americans had comparable treatment, African-Americans actually had lower 1-year mortality rates (with slightly higher rates of rehospitalizations). Some evidence suggests that African-Americans are more often likely than Caucasians to develop diastolic heart failure (a failure of the heart muscle to relax normally), which is often a precursor to systolic heart failure (impaired ability to pump blood). Caucasians tend to develop systolic heart failure first.

According to a 2006 New England Journal of Medicine study, people whose parents had heart failure have a greatly increased risk of developing heart failure, particularly left-ventricular systolic heart failure. Earlier studies have suggested that a family history of early heart failure caused by cardiomyopathies (diseases that damage the heart muscle) may also predispose people to the disease. Researchers are looking for changes in specific genes that might regulate systems involved in heart failure and so increase susceptibility in certain populations.

Chronic alcohol abuse can damage the heart muscles, can cause hypertension, and may prove to be one cause of idiopathic dilated cardiomyopathy. Moderate alcohol consumption, on the other hand (generally defined as 2 drinks a day for men and 1 drink for women), may protect against heart failure. Non-drinkers, though, are not advised to begin drinking.

Coronary artery disease. More than 60% of heart failure cases may be due to coronary artery disease and its risk factors (smoking, sedentary living, obesity).
Heart attack. The injured heart after an attack is at high risk for failure. The improved survival rates from heart attack over the past decades have actually been responsible for the dramatic increase in heart failure rates.
High blood pressure. Hypertension is a significant risk factor and is present in 75% of patients with heart failure.
Diabetes. People with diabetes are at high risk for heart failure, particularly if they also have coronary artery disease. Even blood sugar abnormalities that precede diabetes increase the risk.
Obesity. Obesity is associated with both hypertension and type 2 diabetes, conditions that place people at risk for heart failure. Evidence strongly suggests that obesity itself is a major risk factor for heart failure, particularly in women. In a major 2002 study, about 14% of heart failure cases in women and 11% in men could be attributed to obesity. Both overweight and obese women had a significantly higher than normal risk for heart failure. Only obesity led to a significant risk in men.
Valvular heart disease. Specific valvular conditions that are common in patients with heart failure include aortic stenosis and mitral regurgitation.
Severe emphysema. Chronic obstructive pulmonary disease is a major risk factor for right-side heart failure.

Emphysema is a lung disease involving damage to the air sacs (alveoli).There is progressive destruction of alveoli and the surrounding tissue that supports them. As the disease gets worse, large air cysts take the place of normal lung tissue. Air is trapped in the lungs.

Cardiomyopathies due to various causes, including birth defects, HIV infection, and other infections.
In rare cases, heart failure can occur in women around the time of childbirth, a condition called peripartum cardiomyopathy.

Click the icon to see an image of peripartum cardiomyopathy.

An overactive thyroid (hyperthyroidism) or underactive thyroid (hypothyroidism) can have severe effects on the heart and increase the risk for heart failure.
Amyloidosis. A starchy protein (amyloid) that builds up in tissues and organs can lead to heart failure.
Surviving childhood cancers. Survivors face a risk for developing heart failure in later years, particularly those treated with chemotherapies such as doxorubicin. Newer cancer advances may reduce this risk.
Acute myocarditis. This rare viral infection involves the heart muscle and can produce temporary but potentially life-threatening heart failure.

Long-term use of anabolic steroids (male hormones used to build muscle mass) increases the risk for heart failure. The drug itraconazole (Sporanox), used to treat skin, nail, or other fungal infections, has been linked to heart failure. In 2006, the FDA warned that the cancer drug imatinib (Gleevec) has been associated with heart failure cases. Most patients who took imatinib and developed heart failure had a history of diabetes, high blood pressure, or heart disease.

Complications

At least 20% of hospitalizations in older adults are due to heart failure. For people over age 65, it is the number one cause of death, with nearly 290,000 people dying from this disease each year. Nevertheless, although heart failure produces very high mortality rates, treatment advances in hypertension, heart surgeries, and heart pacemakers are improving survival rates.

The most serious and life-threatening complications of heart failure are:

Arrhythmias (irregular beatings of the heart)
Acute pulmonary edema (fluid in the lungs)

Left-side heart failure tends to be more severe than right-side heart failure, particularly when it is associated with the following conditions:

Coronary artery disease
HIV infection
Amyloidosis (a metabolic disorder than can lead to organ failure)
Chemotherapy that uses the drug doxorubicin

The outlook is better in patients with left-side heart failure associated with:

Idiopathic cardiomyopathy (the cause is unknown)
Heart failure due to childbirth

Weight Issues. If patients with heart failure are overweight to begin with, their condition tends to be more severe. Once heart failure develops, however, an important indicator of a worsening condition is the occurrence of cardiac cachexia, which is unintentional rapid weight loss (a loss of at least 7.5% of normal weight within 6 months).

Impaired Kidney Function. Heart failure weakens the heart’s ability to pump blood. This can affect other parts of the body including the kidneys (which in turn can lead to fluid build-up). Decreased kidney function is common in patients with heart failure, both as a complication of heart failure and as a complication of other diseases associated with heart failure (such as diabetes). Studies suggest that in patients with heart failure, impaired kidney function increases the risks for heart complications including hospitalization and death.

Congestion (Fluid Buildup). In left-sided heart failure, fluid builds up first in the lungs. Later, as right-sided heart failure develops, fluid builds up in the legs, feet, and abdomen. According to one study, patients with severe symptoms who had congestion (fluid buildup) had poorer survival rates than those without fluid build up. Two-year survival rates were 87% in those who were congestion-free compared to 41 - 67% in patients with various signs of congestion (such as swelling, difficulty breathing when lying down, and weight gain from fluid buildup). Fluid buildup is treated with lifestyle measures, such as reducing salt in the diet, as well as drugs, such as diuretics. Sometimes, for hospitalized patients, an ultrafiltration device is used to remove excess water and salt from the body (see Surgery and Devices).

Atrial Fibrillation. This abnormal rhythm is a rapid quivering beat in the upper chambers of the heart. It is a major cause of stroke and very dangerous in people with heart failure.

Left Bundle Branch Block. Left bundle-branch block is an abnormality in electrical conduction in the heart. It develops in about 30% of patients with heart failure and is a major risk factor for serious adverse heart events.

Systolic Blood Pressure. An important 2006 study indicated that patients who arrive at the hospital with heart failure and low systolic blood pressure have a poorer prognosis than those who arrive with high systolic blood pressure. Researchers think that high systolic blood pressure may be a signal for unique clinical characteristics.

Sleep Apnea. With this disorder, a person stops breathing during the night, perhaps hundreds of times, usually for periods of 10 seconds or longer. It is a very strong risk factor for heart failure, and patients with apnea have a higher mortality rate than those who do not.

Depression. The presence of depression indicates a poorer outlook for the heart. Studies indicate that depression may have adverse biologic effects on the immune and nervous systems, blood clotting, blood pressure, blood vessels, and heart rhythms.

Seasonal and Daily Patterns. Studies have shown that more emergency room visits and higher mortality rates occur during winter months and on Mondays in patients with heart failure. One factor in this higher risk may be sudden and strenuous exertion, particularly snow-shoveling, which is associated with a risk for heart attack in people with heart problems.

Diagnosis

Doctors can often make a preliminary diagnosis of heart failure by medical history and careful physical examination.

The medical history risks for heart failure include:

High blood pressure
Diabetes
Poor cholesterol levels
Heart or peripheral vascular disease
Sleep apnea
Thyroid problems
Obesity
Lifestyle factors (smoking, alcohol use)

The following physical signs, along with medical history, strongly suggest heart failure:

Enlarged heart
Irregular heart sounds
Abnormal sounds in the lungs
Swelling or tenderness of the liver
Fluid retention in legs and abdomen
Elevation of pressure in the veins of the neck

Both blood and urine tests are used to check for problems with the liver and kidneys and to detect signs of diabetes. Lab tests can measure:

Cholesterol and lipid levels
Blood sugar (glucose)
Red blood cell count (to rule out anemia)
Blood sugar levels
Thyroid function

Urine tests can be used to assess the presence of a protein called albumin. Albumin in the urine is usually a sign of kidney disease, but even tiny amounts (microalbumin) signal an increased risk for heart failure in people with and without diabetes.

The exercise stress test measures heart rate, blood pressure, and oxygen consumption while a patient is performing physically, usually walking on a treadmill. It is an important diagnostic component in determining heart failure symptoms. Doctors also use exercise tests to gauge long-term outlook and the effects of particular treatments.

An electrocardiogram (ECG) cannot diagnose heart failure, but it can indicate underlying heart problems. It is sometimes called an EKG. The test is simple and painless to perform. It may be used to diagnose:

Enlargement of the heart muscle, which may help to determine long-term outlook
The presence of coronary artery disease
Abnormal cardiac rhythms. A rhythm pattern called a prolonged QT interval, for example, might predict people with heart failure who are at risk for severe complications and would need more aggressive therapies.

The major benefit of an ECG is that it can help determine which patients do not need an echocardiogram, a more accurate (but more expensive) diagnostic test.

The electrocardiogram (ECG, EKG) is used extensively to diagnose heart disease, from congenital heart disease in infants to myocardial infarction and myocarditis in adults. There are several different types of electrocardiograms.

The best diagnostic test for heart failure is echocardiography. Echocardiography is a noninvasive, entirely safe test that uses ultrasound to image the heart as it is beating. Cardiac ultrasounds provide the following information:

Accurate indications of valve function
The amount of blood flow through the heart's chambers
The location of the failure and where it has occurred

Doctors use information from the echocardiogram for calculating the ejection fraction (how much blood is pumped out during each heartbeat), which is important for determining the severity of heart failure.

Radionuclide Ventriculography. Radionuclide ventriculography is an imaging technique that uses a tiny amount of radioactive material (called a trace element). The substance is injected into a patient. As it passes through the bloodstream it is picked up on x-rays. This is a very important imaging technique for patients with heart failure. It is very sensitive in revealing heart enlargement or evidence of fluid accumulation around the heart and lungs. It is typically used in concert with angiography.

Magnetic Resonance Imaging. Magnetic resonance imaging (MRI) scans that use contrast dyes to improve resolution are proving helpful for identifying patients with irreversible heart damage. Damage appears as very bright areas on the scan.

Doctors may recommend angiography if they suspect that blockage of the arteries is contributing to heart failure. This procedure is invasive.

A thin tube called a catheter is inserted into one of the large arteries in the arm or leg.
It is gently guided through the artery until it reaches the heart.
The catheter measures internal blood pressure at various locations, giving the doctor a comprehensive picture of the extent and nature of the heart failure.
Dye is then injected through the tube into the heart.
X-rays called angiograms are taken as the dye moves through the heart and arteries.
These images help locate problems in the heart's pumping action or blockage in the arteries.

Major complications of angiography are rare (about 0.1%) but can occur. They include stroke, heart attacks, and kidney damage. The more experienced the medical center in this procedure, the lower the risk.

Click the icon to see an image of cardiac catheterization.

Researchers are looking for biologic factors (called biomarkers) that will confirm a diagnosis or suggest a better or worse prognosis. Many are under investigation.

Tumor Necrosis Factor. Elevated levels of tumor necrosis factor (TNF) may be a very strong and accurate predictor of a poor outlook. This immune substance is known to be a potent substance in the inflammatory process.

Natriuretic Peptides. Natriuretic peptides are substances that help regulate salt and water balance in the body. Levels of these peptides increase as heart failure symptoms worsen. Blood tests for brain natriuretic peptide (BNP) are now used to help diagnose heart failure. There are two types of BNP tests: The enzyme-linked immunosorbent assay (ELISA) and the radioimmunosorbent assay (RIA). Research from 2006 suggested that the ELISA test may be more accurate, but it is also more expensive.

BNP testing can be very helpful in correctly diagnosing heart failure in patients who come to the emergency room complaining of shortness of breath (dyspnea). A 2006 study indicated that this test can also help predict which patients with dyspnea are at greatest risk of dying within a year from heart failure.

Brain Metabolites. High levels of a compound called N-acetylaspartate, generated as a byproduct of chemical processes in the brain, may indicate a poor outlook.

Treatment

Guidelines for evaluating the severity of heart failure and determining treatments use a staging system that is similar to the one used for major cancers:

Stage A: Patients are at high risk for heart failure, but there is no evidence of structural damage to the heart. Risk factors include high blood pressure, heart diseases, diabetes, obesity, metabolic syndrome, and previous use of medications that damage the heart (such as some chemotherapy).
Stage B: Patients have a structural heart abnormality but no symptoms of heart failure. Abnormalities include left ventricular hypertrophy and low ejection fraction, asymptomatic valvular heart disease, and a previous heart attack.
Stage C: Patients have a structural abnormality and current or previous symptoms of heart failure, including shortness of breath, fatigue, and difficulty exercising.
Stage D: Patients have end-stage symptoms that do not respond to standard treatments.

According to expert guidelines, the first step in managing heart failure is to treat the primary conditions causing or complicating heart failure. These include:

Coronary artery disease. Treatment includes a healthy diet, exercise, smoking cessation, medications, and, possibly, bypass or angioplasty. [See In-Depth Report #3: Coronary artery disease and angina.]
Cholesterol and lipid problems. Treatments include lifestyle management and medications, especially statins. [See In-Depth Report #23: Cholesterol.]
High blood pressure. A normal systolic blood pressure is considered below 120 mm Hg, and a normal diastolic blood pressure is below 80 mm Hg. Patients with diabetes or chronic kidney disease should maintain blood pressure readings of 130/80 or less, while other patients with high blood pressure should aim for readings no higher than 140/90. Effective reduction of blood pressure reduces the risk of heart failure by 30 - 50%. [See In-Depth Report #14: High blood pressure.]
Diabetes. Treating diabetes is extremely important for reducing the risk for heart disease. ACE inhibitors are especially beneficial, particularly for people with diabetes. Recent research suggests that metformin, a drug used to treat diabetes, may also help prevent heart failure. [See In-Depth Report #60: Diabetes - type 2; and In-Depth Report #9: Diabetes - type 1.]
Valvular abnormalities such as aortic stenosis and mitral regurgitation. Surgery may be required.
Abnormal health rhythms (arrhythmias). Ventricular assisted devices, notably biventricular pacers (BVPs), are proving to be important in preventing hospitalizations for patients with these conditions.
Anemia. Giving erythropoietin (EPO) and iron injections to patients with heart failure and underlying anemia not only reverses the anemia, but may markedly improve heart symptoms as well. [See In-Depth Report #57: Anemia.]
Thyroid function. Various medications are used to treat overactive thyroid (hyperthyroidism) or underactive thyroid (hypothyroidism). [See In-Depth Report #38: Hypothyroidism.]
Sleep apnea. Continuous positive airway pressure (CPAP) is an effective treatment for sleep apnea. CPAP may help reduce systolic blood pressure and improve left ventricular systolic function. [See In-Depth Report#65:Sleep apnea.]

Click the icon to see an image of CPAP treatment.

Treatments for patients with Stage B risk for heart failure include all of the treatments recommended in Stage A. In addition, the following types of drugs and devices may be recommended for some patients. These include:

Angiotensin-converting enzyme (ACE) inhibitors for patients with a recent or past history of heart attack. Also for patients who have not had a heart attack if they have a low left ventricular ejection fraction (LVEF) and no heart failure symptoms. A reduced LVEF indicates that the heart’s left ventricle is not pumping blood efficiently.
Beta blockers for patients with a recent or past history of heart attack. Also for patients who have not had a heart attack but who do have reduced LVEF without heart failure symptoms.
Angiotensin-receptor blockers (ARBs) for patients who have had a heart attack or have low LVEF, but who cannot take ACE inhibitors.
Implantable defibrillators for patients who have weakened heart pumps (ischemic cardiomyopathy), who had a heart attack more than 40 days prior, and who have low LVEF.

Treat conditions as recommended in Stage A plus:

Restrict dietary salt. Lowering salt in the diet can help diuretics work better.
ACE inhibitors, beta blockers, and diuretics are recommended for most patients.
ARBs are recommended for patients who cannot tolerate ACE inhibitors.
Aldosterone inhibitors or digitalis may be used for some patients.
A hydralazine and nitrate combination (BiDil) may be used for African-American patients who are taking an ACE inhibitor and beta blocker and who still have heart failure symptoms.
Avoid drugs that can worsen heart failure symptoms. These include nonsteroidal anti-inflammatory drugs (NSAIDs), most calcium channel blockers, and most drugs used to treat irregular heart rhythms (arrhythmia).
Exercise training for appropriate patients.
Biventricular pacemakers and implantable defibrillators for some patients.

Treatment includes appropriate measures used for Stages A, B, and C plus:

Heart transplantation referral for appropriate patients.
Left-ventricular assist devices (LVADs) as permanent therapy for patients who are not candidates for heart transplants. LVADs are surgically implanted to help pump blood through the body.
Hospice and end-of-life care information for patients and families.

Medications

Many different medications are used in the treatment of heart failure. They include:

Angiotensin-converting enzyme (ACE) inhibitors
Angiotensin-receptor blockers (ARBs)
Beta blockers
Diuretics
Aldosterone blockers
Digitalis
Hydralazine and nitrates
Statins
Nesiritide (Natrecor)
Aspirin

Angiotensin-converting enzyme (ACE) inhibitors are among the most important drugs for treating patients with heart failure. ACE inhibitors open blood vessels and decrease the workload of the heart. They are used to treat high blood pressure but can also help improve heart and lung muscle function. Major studies suggest that ACE inhibitors may reduce the risk of death, heart attack, and hospital admissions by 28% in patients with existing heart failure.

ACE inhibitors are particularly important for patients with diabetes. A large study reported that patients with diabetes who took these drugs had fewer heart attacks and lower overall mortality rates than patients who took other types of high blood pressure medications. ACE inhibitors may also help slow progression of kidney disease, in addition to controlling blood pressure.

Choosing an ACE inhibitor. ACE inhibitors treat Stage A high-risk conditions such as high blood pressure, heart disease, and diabetic nerve disorders (neuropathy). They also treat Stage B patients who have had a heart attack or who have left ventricular systolic disorder, and Stage C patients with heart failure. Specific brands and stages include:

Benazepril (Lotrel) -- (Stage A)
Captopril (Capoten) -- (Stages A, B, C)
Enalapril (Vasotec) -- (Stages A, B, C)
Fosinopril (Monopril) -- (Stages A, C)
Lisinopril (Prinivil, Zestril) -- (Stages A, B, C)
Moexipril (Univasc) -- (Stage A)
Perindopril (Aceon) -- (Stage A)
Quinapril (Accupril) -- (Stages A, C)
Ramipril (Altace) -- (Stages A, B, C)
Trandolapril (Mavik) -- (Stages A, B, C)

Side Effects of ACE Inhibitors:

Low blood pressure is the main side effect of ACE inhibitors. This can be severe in some patients, especially at the start of therapy.
Irritating cough is a common side effect, which some people find intolerable. Although all ACE inhibitors can have this side effect, sometimes switching to another brand will reduce this symptom.
Although ACE inhibitors can protect against kidney disease, they also increase potassium retention in the kidneys. This increases the risk for cardiac arrest if potassium levels become too high. Because of this action, they are not generally given with potassium-sparing diuretics or potassium supplements.
A rare but severe side effect is granulocytopenia, which is an extreme reduction in infection-fighting white blood cells.
In very rare cases, patients suffer a sudden and severe allergic reaction called angioedema that causes swelling in the eyes and mouth and may close off the throat.

Patients who have difficulty tolerating ACE inhibitor side effects are usually switched to an angiotensin-receptor blocker (ARB).

ARBs, also known as angiotensin II receptor antagonists, are similar to ACE inhibitors in their ability to open blood vessels and lower blood pressure. They may have fewer or less-severe side effects than ACE inhibitors, especially coughing, and are sometimes prescribed as an alternative to ACE inhibitors. Some patients with heart failure take an ACE inhibitor along with an ARB.

Brands and Indications. ARBs are used to treat Stage A high-risk conditions such as high blood pressure and diabetic nerve disorders (neuropathy). They are also used to treat Stage B patients who have had a heart attack or who have left ventricular systolic disorder, and Stage C patients with heart failure. Specific brands, and the stage of heart failure they are used for, are listed below.

Candesartan (Atacand) -- (Stages A, C)
Eprosartan (Teveten) -- (Stage A)
Irbesartan (Avapro) -- (Stage A)
Losartan (Cozaar) -- (Stages A, B)
Olmesartan (Benicar) -- (Stage A)
Telmisartan (Micardis) -- (Stage A)
Valsartan (Diovan) -- (Stages A, B, C)

Common Side Effects

Low blood pressure
Dizziness and lightheadedness
Raised potassium levels
Drowsiness

Beta blockers are almost always used in combination with other drugs, such as ACE inhibitors and diuretics. They help slow heart rate and lower blood pressure. Research presented at the 2006 American College of Cardiology meeting indicated that beta-blockers are an important treatment for most patients with left ventricular heart failure. Data from the study found that the beta blocker carvedilol (Coreg) significantly lowered the risk of death or rehospitalization within 3 - 6 months after hospital discharge.

Beta blockers can help patients with heart failure by:

Treating high blood pressure, angina, arrhythmias, and preventing heart attack in high-risk patients.
Preventing left ventricular remodeling in patients with enlarged heart chambers and weakened heart muscles (dilated cardiomyopathy), and in those who have suffered a first heart attack.
Blocking inflammatory immune factors called cytokines, including tumor necrosis factor (TNF). TNF may play a key role in the process leading to heart failure.
Preventing norepinephrine (adrenaline) from binding to heart cells. Elevated levels of norepinephrine, a stress hormone, can overstimulate the failing heart and are associated with severe heart failure.

Brands and Indications. Beta blockers treat Stage A high blood pressure. They are also treat Stage B patients (both those who have had a heart attack and those who have not had a heart attack but who have heart damage). Recent guidelines identify three drugs best for treating Stage C patients with heart failure. Specific brands and stages include:

Acebutolol (Sectral) -- (Stage A)
Atenolol (Tenormin) -- (Stages A, B)
Betaxolol (Kerlone) -- (Stage A)
Bisoprolol (Zebeta) -- (Stages A, C)
Cartelol (Cartrol) -- (Stage A)
Carvedilol (Coreg) -- (Stages A, B, C)
Labetalol (Trandate) -- (Stage A)
Metoprolol succinate (Toprol XL) -- (Stages A, C)
Metoprolol tartrate (Lopressor) -- (Stages A, B)
Nadolol (Corgard) -- (Stage A)
Penbutolol (Levatol) -- (Stage A)
Pindolol (Visken) -- (Stage A)
Propranolol (Inderal) -- (Stages A, B)
Timolol (Blocadren, Timolide) -- (Stages A, B)

Beta Blocker Concerns

Do not abruptly stop taking these drugs. The sudden withdrawal of beta blockers can rapidly increase heart rate and blood pressure. Your doctor may want you to slowly decrease the dose before stopping completely.
Beta blockers are categorized as non-selective or selective. Non-selective beta blockers such as carvedilol and propranolol can narrow bronchial airways. Patients with asthma, emphysema, or chronic bronchitis should not use these beta blockers.
Beta blockers can lower HDL (“good”) cholesterol.
These drugs can hide warning signs of low blood sugar (hypoglycemia) in patients with diabetes.
Beta blockers are usually used in combination with ACE inhibitors, but the two drugs are not started at the same time. Research presented at the 2005 European Society of Cardiology meeting indicates that either a beta blocker or an ACE inhibitor can be prescribed at first, and the other drug added on later.

Common Side Effects

Fatigue and lethargy
Vivid dreams and nightmares
Depression
Memory loss
Dizziness and lightheadedness
Reduced ability to exercise
Coldness in extremities (legs, toes, arms, hands)

Check with your doctor about any side effects. Do not stop taking these drugs on your own.

Diuretics cause the kidneys to rid the body of excess salt and water. Fluid retention is a major symptom of heart failure. Aggressive use of diuretics can help eliminate excess body fluids, while reducing hospitalizations and improving exercise capacity. These drugs are also important to help prevent heart failure in patients with high blood pressure. In addition, certain diuretics, notably spironolactone (Aldactone), block aldosterone, a hormone involved in heart failure. This drug class is beneficial for patients in late stages of heart failure (Stages C and D).

Diuretic Types and Brands. Diuretics come in many brands and are generally inexpensive. Some need to be taken once a day, some twice a day. Treatment is usually started at a low dose and gradually increased. Diuretics are virtually always used in combination with other drugs, especially ACE inhibitors and beta blockers. There are three main types of diuretics:

Potassium-sparing diuretics. These include amiloride (Midamor), spironolactone (Aldactone), and triamterene (Dyrenium).
Thiazide diuretics. These include chlorothiazide (Diuril), chlorthalidone (Hygroton), indapamide (Lozol), hydrochlorothiazide (Esidrix, HydroDiuril), and metolazone (Mykrox, Zaroxolyn).
Loop diuretics. Because loop diuretics act faster than other diuretics it is important to avoid dehydration and potassium loss. Loop diuretics include bumentanide (Bumex), furosemide (Lasix), and torsemide (Demadex).

Problems with Diuretics. Loop and thiazide diuretics deplete the body's supply of potassium, which, if left untreated, increases the risk for arrhythmias. Arrhythmias are heart rhythm disturbances that can, in rare instances, lead to cardiac arrest. In such cases, doctors will prescribe lower doses of the current diuretic, recommend potassium supplements, or use potassium-sparing diuretics either alone or in combination with a thiazide. Potassium-sparing drugs have their own risks, which include dangerously high levels of potassium in people with existing elevated levels of potassium or in those with damaged kidneys. However, all diuretics are generally more beneficial than harmful.

Common Side Effects

Fatigue
Depression and irritability
Urinary incontinence
Reduced sexual drive

Aldosterone is a hormone that is critical in controlling the body's balance of salt and water. Excessive levels may play important roles in hypertension and heart failure. Drugs that block aldosterone are prescribed for some patients with Stage C heart failure.

Spironolactone (Aldactone, Spirinol) is both a potassium-sparing diuretic and an aldosterone blocker. A major study of patients with heart failure found that spironolactone reduced death rate by 30%. Like all medications for heart failure, it must be used with care; elevated potassium levels are a potential risk of therapy.
Eplerenone (Inspra), a newer aldosterone blocker, has been specifically approved for treatment of heart failure. It is prescribed for patients who have heart failure following a heart attack. Its actions are similar to potassium-sparing diuretics and, like these drugs, it poses some risk for high potassium levels.

Digitalis is derived from the foxglove plant. It has been used to treat heart disease since the 1700s. Digoxin (Lanoxin) is the most commonly prescribed digitalis preparation. Digoxin decreases heart size and reduces certain heart rhythm disturbances (arrhythmias).

Unfortunately, digitalis does not reduce mortality rates, although it does reduce hospitalizations and worsening of heart failure. Controversy has been ongoing for more than 100 years over whether the benefits of digitalis outweigh its risks and adverse effects.

Digitalis may be useful for patients with left-ventricular systolic dysfunction who do not respond to other drugs (diuretics, ACE inhibitors). It is also used for patients who have atrial fibrillation.

Digitalis does not appear to help patients with left-ventricular diastolic heart failure. It may be harmful in patients with right-ventricular heart failure and those who stop taking digoxin after using it in combination with ACE inhibitors.

Side Effects and Problems. While digitalis is generally a safe drug, it can have toxic side effects due to overdose or other accompanying conditions. The most serious side effects are arrhythmias (abnormal heart rhythms that can be life-threatening). Early signs of toxicity may be irregular heartbeat, nausea and vomiting, stomach pain, fatigue, visual disturbances (such as yellow vision, seeing halos around lights, flickering or flashing of lights), and emotional and mental disturbances.

Many factors increase the chance for side effects.

Advanced age
Low blood potassium levels (which may be caused by diuretics)
Hypothyroidism
Anemia
Valvular heart disease
Impaired kidney function

Digitalis also interacts with many other drugs, including quinidine, amiodarone, verapamil, flecainide, amiloride, and propafenone.

A blood test that monitors drug levels in patients taking the drug can limit the rate of toxicity to about 2%. For most patients with mild-to-moderate heart failure, low-dose digoxin may be as effective as higher doses. If side effects are mild, patients should still consider continuing with digitalis if they experience other benefits.

Hydralazine and nitrates are two older drugs that help relax arteries and veins, thereby reducing the heart's workload and allowing more blood to reach the tissues. In 2005, the FDA approved BiDil, a drug that combines isosorbide dinitrate and hydralazine. BiDil is approved to specifically treat heart failure in African-Americans. African-Americans have a particularly high risk for heart failure. BiDil is the first drug approved for a specific racial group. The Food and Drug Administration (FDA) based its approval on a landmark 2004 study published in the New England Journal of Medicine, which showed that African-Americans who took the drug were 43% more likely to survive heart failure than patients who took placebo. Some experts suggest that BiDil could also benefit other racial groups.

Statins are important drugs used to lower cholesterol and to prevent heart disease leading to heart failure. These drugs include lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), fluvastatin (Lescol), atorvastatin (Lipitor), and rosuvastatin (Crestor). In 2007, the FDA approved atorvastatin to reduce the risks for hospitalization for heart failure in patients with heart disease.

In a 2006 Journal of the American Medical Association study, patients with heart failure who began taking a statin drug had a 24% lower relative risk of death and a 21% lower relative risk of hospitalization for heart failure than patient who did not take a statin. Statins appeared to help these patients regardless of whether or not they had co-existing coronary heart disease.

Aspirin is a type of non-steroid anti-inflammatory (NSAID). A 2005 study in the Journal of the American College of Cardiology indicated that aspirin is important for preventing heart failure death in patients with heart disease, and can safely be used with ACE inhibitors. However, some research has suggested that NSAIDs may increase the risk of heart failure for patients with a history of heart disease, especially when used in combination with ACE inhibitors or diuretics. Patients with heart disease should ask their doctor which NSAIDs are right for them.

Nesiritide treats patients who have arrived at a hospital with decompensated heart failure. Decompensated heart failure is a life-threatening condition in which the heart fails over the course of minutes or a few days, often as the result of a heart attack or sudden and severe heart valve problems. However, nesiritide may cause serious kidney damage.

In 2005, the FDA released recommendations from an expert panel concerning the appropriate and inappropriate use of nesiritide. The panel emphasized that nesiritide should be used to treat only patients with decompensated heart failure who have shortness of breath (dyspnea) and trouble breathing. The drug should not be a replacement for diuretics.

Despite these warnings, some doctors have prescribed nesiritide “off-label” to treat patients with severe heart failure outside of a hospital setting. Research presented at the 2007 American College of Cardiology annual conference criticized this practice by demonstrating that nesiritide plus standard treatment does not reduce the risk of heart- or kidney-related death or hospitalization. In addition, the research suggested some concerns about nesiritide’s overall safety.

Tolvaptan. Tolvaptan is an investigational drug that is being studied in combination with standard therapy for treatment of heart failure. It is especially being investigated for acute decompensated heart failure, a type of heart failure categorized by fluid build-up in the lungs (pulmonary edema) for which there are few available treatments. In patients hospitalized with heart failure, tolvaptan plus standard drugs improved breathing problems (dyspnea) and reduced fluid accumulation (edema) and body weight, according to two studies published in 2007 in the Journal of the American Medical Association. However, the drug did not appear to reduce the risk of re-hospitalization or death.

Levosimendan. Levosimendan is an experimental inotropic drug that is being investigated as a treatment for severely ill patients with heart failure. It belongs to a new class of drugs called calcium sensitizers that may help improve heart contractions and blood flow. Clinical trials suggest that levosimendan may improve survival in patients hospitalized for heart failure. The drug also appears to reduce levels of BNP (brain natriuretic peptide), a chemical marker for heart failure severity.

Prograf. Tacrolimus (Prograf) was approved in 2006 to help prevent organ rejection in patients who have received a heart transplant. The drug suppresses the immune system. Patients who receive this drug are at increased risk of developing lymphoma (a cancer of the immune system).

Surgery and Devices

Revascularization surgery helps to restore blood flow to the heart. It can treat blocked arteries in patients with coronary artery disease and may help selected patients with heart failure. Surgery types include coronary artery bypass graft (CABG) and percutaneous coronary intervention (PCI). CABG is a traditional type of open heart surgery. PCI, also called angioplasty, uses a catheter to inflate a balloon inside the artery. A metal stent may also be inserted during a PCI procedure. [See In-Depth Report#03:Coronary artery disease.]

A 2006 study suggested that early treatment with revascularization surgery may be particularly important for patients with systolic heart failure, a condition that occurs when the heart does not pump out enough blood. This condition has a very high death rate. Researchers found that CABG or PCI surgery halved the risk of dying compared to standard drug therapy. Patients in the study first underwent a positron emission tomography (PET) test to determine if they would be good candidates for surgery.

Click the icon to see an illustrated series detailing coronary artery balloon angioplasty.

Click the icon to see an illustrated series detailing heart bypass surgery.

In appropriate patients, mitral valve surgery may significantly reduce the severity of heart failure. In a study of 92 patients with late-stage heart failure and faulty valves, reconstruction of the heart's mitral valve drastically improved heart function.

An experimental mesh "heart sock" is being investigated as an adjunct to mitral valve repair surgery. Research presented at the 2004 American Heart Association Scientific Sessions suggested that the device reduced the progression of heart failure and halved the need for transplant surgery. The "sock" helps realign the shape of the heart and improve heart function. To date, it has been tested in patients with dilated cardiomyopathy.

Ventricular Remodeling. Ventricular remodeling (also called partial left ventriculectomy or the Batista procedure, after its inventor) may allow some patients with dilated cardiomyopathy to avoid a heart transplant.

The procedure involves the following:

The surgeon first performs ventriculectomy, which is the removal of a section of healthy heart muscle weighing about 3 ounces.
The surgeon then reshapes the heart to a more normal size and form.
Any faulty heart valves are repaired.

Ventricular remodeling is still relatively new, and mortality rates are very high. Studies on long-term improvement are mixed. More research is needed to target the patients who would most benefit.

Patients who suffer from severe heart failure and whose symptoms do not improve with drug therapy or mechanical assistance may be candidates for heart transplantation. Some 3,600 people are awaiting a transplant, although only about 2,000 operations are performed each year.

The most important factor for heart transplant eligibility is overall health. Chronological age is less important. Most heart transplant candidates are between the ages of 50 – 64 years. About 72% of transplant patients are male, and 70% are white.

While the risks of this procedure are high, the 1-year survival rate is about 86% for men and 84% for women. The 3-year survival rate is 78% for men and 75% for women. Five years after a heart transplant, about 71% of men and 67% of women remain alive. In general, the highest risk factors for death 3 or more years after a transplant operation are coronary artery disease and the adverse effects (infection and certain cancers) of immunosuppressive drugs used in the procedure. The rejection rates in older people appear to be similar to those of younger patients.

In 2004, the FDA approved a temporary artificial heart (Syncardia) intended to keep patients alive in the hospital while they waited for a heart transplant. In 2006, the FDA approved the first permanent implantable artificial heart (AbiCor). The AbiCor is available only for patients who are not eligible for a heart transplant and who are not expected to live more than a month without medical treatment. The device requires a large chest cavity, which means that most women will not be eligible for it. Of the 14 men who have received the AbiCor, the average survival was less than 5 months after surgery. Only one patient was discharged from the hospital. The device’s manufacturer is working on a new model that it hopes will extend survival by as long as 5 years.

A growing array of heart devices and machines are changing the face of heart failure treatment. They have gained widespread acceptance for use as a bridge to transplant in patients who are on medications but still have severe symptoms and are awaiting a donor heart. Increasingly, though, doctors are exploring the possibility that such devices may be satisfactory treatments themselves, forestalling the need for a transplant altogether in some patients.

Ventricular Assist Devices (VADs). Ventricular assist devices are machines that help improve pumping actions. Several models with slightly different features are in use or under investigation. Some include the following:

Left ventricular assist device (LVAD) are used for patients whose heartbeat has slowed dangerously (a condition called bradycardia) to help take over the pumping action of the failing heart. Studies suggest that in some people the use of an LVAD may allow some of the damaged heart muscle to heal, perhaps even helping some patients avoid heart transplants. These devices are also being studied in combination with drug therapy to help recover heart function and improve patients’ chances for survival. Until recently, these machines required remaining in the hospital. Smaller battery-powered LVAD units, however, are allowing many patients to leave the hospital and are proving to be effective bridges to heart transplants in adults. The HeartMate, for example, a portable LVAD about the size of a portable CD player (2 in. by 4 in.), is implanted in the upper abdomen. The implanted device plugs into an external power base, which is used when the patient is at rest to recharge the battery and provide continuous power.
Fully implanted miniature artificial pumps that assist the heart (not replace it) are also being tested. The DeBakey ventricular assist device (VAD) for example, is a tiny heart pump that weighs less than 4 ounces. It has been approved in Europe and is being tested in the United States. The Jarvik 2000 heart pump is also showing promise.
The intra-aortic balloon pump (IABP) is helpful for maintaining heart function in people with left-side failure waiting for transplants and in those who develop a sudden and severe deterioration of heart function. The IABP is an implanted thin balloon that is usually inserted into the artery in the leg and threaded up to the aorta leading from the heart. Its pumping action is generated by inflating and deflating the balloon at certain rates. Usually, it is used only for short periods, but some studies indicate that patients may be able to use it safely for somewhat longer periods (an average duration of 23 days in one study).

There are risks involved with many of these devices, including bleeding, blood clots, and right-side heart failure. Infections are a particular hazard.

Pacers (Pacemakers). Pacers, or pacemakers, help regulate the heart’s beating action, especially when the heart beats too slowly. Biventricular pacers (BVPs) are a special type of pacemaker used for patients with heart failure. Because BVPs help the heart’s left and right chambers beat together, this treatment is called cardiac resynchronization therapy (CST). BVPs may particularly help heart failure patients who have left bundle branch block, a condition in which the electrical impulses in the heart do not follow their normal pattern. In general, BVPs are recommended for patients with moderate-to-severe heart failure. A small 2006 study suggested that a defibrillator may be better suited for patients with moderate heart failure, while indicating a BVP might be best for patients with severe heart failure.

Implantable Cardioverter-Defibrillators. Devices called implantable cardioverter-defibrillators (ICDs), which are sometimes combined with pacemakers, work well for preventing arrhythmias (abnormal heart rhythms) in heart failure patients. Studies have also found them effective in preventing sudden death from severe rhythm disturbances in patients with weakened hearts from previous arrhythmias and in patients with genetic hypertrophic cardiomyopathy. Patients who have an ICD should avoid taking fish oil supplements. A 2005 Journal of the American Medical Association study found that omega-3 fatty acid supplements may increase the risk of rapid heart beat (ventricular tachycardia) or irregular heart rhythm (ventricular fibrillation) in some of these patients.

ICDs have many benefits, and recent expert guidelines recommend that they be used in more patients with heart failure. However, in June 2005, certain ICD models and biventricular pacemaker-defibrillators were recalled by the manufacturer because of a circuitry flaw that prevents the devices from delivering therapeutic electrical shocks when needed. The problem may result in patient death. Although the FDA did not make any specific recommendations, the agency encourages patients who may have such a device to ask their doctor if they should have it removed or replaced.

In April 2006, two studies published in the Journal of the American Medical Association evaluated data concerning the safety and reliability of implantable pacemakers and defibrillators. The studies found that from 1990 – 2002, pacemakers became increasingly reliable. From 1998 – 2002, ICDs had a significantly higher rate of malfunction than pacemakers, although the reliability of ICDs appeared to improve from 2003 – 2004.

In October 2006, the U.S. Heart Rhythm Society issued recommendations for doctors, manufacturers, and the FDA to help improve communication concerning performance and recalls of ICDs and pacemakers. Experts stress that the chance of an ICD or pacemaker saving a person’s life far outweigh the possible risks of these devices failing.

Ultrafiltration devices are used in hospitals to pump excess water and salt from the body. Catheters are inserted into several of the patient’s veins. The catheters are connected to a blood filter device. Blood is withdrawn through one of the catheters and filtered in the device to remove excess fluid. The filtered blood is then returned to the patient through another catheter. A 2006 study reported that ultrafiltration devices may work better than diuretic drugs for patients with acute decompensated heart failure (ADHF). ADHF is heart failure that has rapidly deteriorated so that patients require immediate hospitalization.

Lifestyle Changes

Between 30 - 47% of patients who require hospitalization for heart failure are back in the hospital within 6 months. Many people return because of lifestyle factors such as poor diet, failure to comply with medications, and social isolation.

In one study, elderly people who had no emotional support at home had triple the risk of a heart attack after hospitalization for heart failure than those who did have such support. (Women had eight times the risk.) In another study, the greatest risk factor for death and readmission to the hospital after a first hospitalization was being single, regardless of the health of the patient at discharge. A third study confirmed that a strong marriage predicted long-term survival. Evidence continues to mount that programs that offer intensive follow-up to ensure that the patient complies with lifestyle changes and medication regimens at home are reducing rehospitalization rates and improving survival. Patients without available rehabilitation programs should seek support from local and national heart associations and groups.

Patients should weigh themselves each morning and keep a record. Any changes are important:

A sudden increase in weight of more than 2 - 3 pounds may indicate fluid accumulation and should prompt an immediate call to the doctor.
Rapid wasting weight loss over a few months is a very serious sign and may indicate the need for surgical intervention.

Whole Grains. Evidence suggests that daily consumption of whole grain foods may help prevent heart failure. In research presented at a 2007 American Heart Association conference, people who ate whole-grain breakfast cereals seven or more times a week had a 28% lower risk of developing heart failure than those who never ate these cereals.

Mediterranean Diet. Evidence suggests that the Mediterranean diet helps protect the heart and may even reduce the risk for heart failure after a first heart attack. The diet emphasizes whole grains, fish, olive oil, garlic, and moderate daily intake of wine. There are several variations to the Mediterranean diet but general recommendations include:

Limit red meats.
Limit dairy products.
Eat moderate amounts of fish and poultry. Fish is the diet’s main protein source. Some studies suggest that fish is the primary heart-protective ingredient in this diet. However, patients who have an implantable defibrillator should not take fish oil supplements. A 2005 study suggested that these supplements may worsen heart rhythm problems in some patients.
Eat plenty of fresh fruits and vegetables, nuts, legumes, beans, and whole grains.
Daily glass or two of wine. Light-to-moderate alcohol use may reduce the risk for heart failure, (but heavy alcohol consumption is a risk factor).
Plenty of fresh fruits and vegetables, as well as nuts, legumes, beans, and whole grains.

DASH Diet. The Dietary Approaches to Stop Hypertension (DASH) diet is an important lifestyle step in managing blood pressure. It may also be useful for many patients with heart failure. This diet is not only rich in important nutrients and fiber but also includes foods that contain two and a half times the amounts of electrolytes, potassium, calcium, and magnesium found in the average American diet.

Potassium-rich foods, which are important for patients with heart failure, include bananas, oranges, prunes, cantaloupes, carrots, spinach, celery, alfalfa, mushrooms, lima beans, potatoes, avocados, and broccoli. However, patients who take potassium-sparing diuretics or ACE inhibitors, and those with kidney dysfunction, may have to restrict their potassium intake.

The DASH diet is rich in whole grains and fresh fruits and vegetables. It stresses avoiding saturated fats, as any healthy diet does, although it includes calcium-rich dairy products that are non- or low-fat. When choosing fats, the diet recommends monounsaturated oils such as olive or canola oil.

Salt Restriction. People with high blood pressure are generally urged to restrict salt, although certain people may be more susceptible to its effects. For example, a high intake of salt may be an independent risk factor for the development of heart failure in people who are overweight. All patients with heart failure should limit their salt intake, and in severe cases, very stringent salt restriction may be necessary. Patients should not add salt to their cooking and their meals. They should also avoid foods high in sodium. These salty foods include ham, bacon, hot dogs, lunch meats, prepared snack foods, dry cereal, cheese, canned soups, soy sauce, and condiments. Some patients may need to reduce their water intake as well. People with high cholesterol levels or diabetes require additional dietary precautions. [See In-Depth Report #43: Heart-healthy diet. ]

People with heart failure used to be discouraged from exercising. Now, experts think that exercise, when performed under medical supervision, is extremely important for many patients with stable conditions. Studies have reported that patients with stable conditions who engage in regular moderate exercise (three times a week) experience a better quality of life and lower mortality rates than those who do not exercise.

The following guidelines are critical:

Experts warn that exercise is not appropriate for all patients with heart failure. If you have heart failure, always consult your doctor before starting an exercise program.
People who are approved for, but not used to, exercise should start with 5 - 15 minutes of easy exercise with frequent breaks. Although the goal is to build up to 30 - 45 minutes of walking, swimming, or low-impact aerobic exercises three to five times every week, even shorter times spent exercising are useful.

Studies report benefits from specific exercises:

Progressive strength training may be particularly useful for patients with heart failure since it strengthens muscles, which commonly deteriorate in this disorder. Strength training typically uses light weights, weight machines, or even the body's weight (leg raises or sit-ups, for example). Even performing daily handgrip exercises can improve blood flow through the arteries.
Patients who exercise regularly using supervised treadmill and stationary-bicycle exercises can increase their exercise capacity by 14 - 36%. In one study, patients as old as 91 years increased their oxygen consumption significantly after 6 months of supervised treadmill and stationary bicycle exercises. Exercising the legs may help correct problems in heart muscles. In one study, patients who did leg extension exercises for 8 weeks had higher levels of an enzyme involved in forming new blood vessels. Exercise has also been associated with reduced inflammation in blood vessels.
Dancing may be a fun and beneficial alternative to standard aerobic exercise, according to research presented at the 2006 annual meeting of the American Heart Association. In a study of patients with stable chronic heart failure, dancing helped improve cardiopulmonary fitness, arterial elasticity, and quality of life. Patients in the study danced fast and slow waltzes for 21 minutes, three times a week.

Bed rest may be required in cases of severe heart failure. To reduce congestion in the lungs, the patient's upper body should be elevated. For most patients, resting in an armchair is better than lying in bed. Relaxing and contracting leg muscles is important to prevent clots. As the patient improves, a doctor will progressively recommend more activity.

Experts have traditionally recommended that people with heart failure avoid warm baths, which can increase the heart rate. Some studies now report that carefully controlled bathing for short periods may not be harmful and may actually be beneficial, reducing irregular heart beats and increasing cardiac output and ejection fraction. Warm water may behave like a vasodilating drug, opening up the vessels gently and improving circulation. In clinical trials, patients sat in warm water or a dry sauna for 10 minutes, with their bodies tilted at a 45 degree angle.

Warning Note: Prolonged periods in hot or even warm conditions can be dangerous. Any patient with heart failure should consult their doctor first, not bathe unaccompanied, and be sure that the temperature does not go above 106° Fahrenheit for water bathing or 140° Fahrenheit for dry saunas.

Stress reduction techniques, such as meditation and relaxation response methods, may have direct physical benefits for lowering stress hormones. These hormones include cortisol, which suppresses the immune system, and norepinephrine (also known as adrenaline), the chemical messenger associated with heart dysfunction.

Patients with heart failure may resort to alternative remedies. Such remedies are often ineffective and may have severe or toxic effects. Of particular note for patients with heart failure is an interaction between St. John's wort (an herbal medicine used for depression) and digoxin (a heart drug). St. John's wort can significantly interfere with this drug.

Arginine. Some evidence suggests that arginine (also called L-arginine) may have some benefit. This amino acid appears to reduce endothelin, a protein that causes blood vessel constriction and is found in high amounts in patients with heart failure. It can have adverse effects, however, including gastrointestinal problems. It can also lower blood pressure and change levels of certain chemicals and electrolytes in the body. It may increase the risk for bleeding. Some people have an allergic reaction to it, which in same cases may be severe. It may worsen asthma.

Coenzyme Q10 and Vitamin E. Small studies have suggested that coenzyme Q10 (CoQ10) may help patients with heart failure, particularly when combined with vitamin E. CoQ10 is a vitamin-like substance found in organ meats and soybean oil. More recent studies, however, have found that CoQ10 and vitamin E do not help the heart or prevent heart disease. According to a 2005 Journal of the American Medical Association study, vitamin E supplements can actually increase the risk of heart failure, especially for patients with diabetes or vascular diseases.

Crataegus Extract. An herbal remedy, Crataegus Extract WS1442, which is made from the leaves of the Crataegus tree, may have antioxidant properties that can help patients with heart failure. In a study presented at the 2007 American College of Cardiology annual meeting, over 2,000 patients with severe heart failure were randomized to receive either Crataegus Extract or placebo (plus standard drug treatment) for 2 years. The researchers noted a 20% reduction in heart-related deaths among patients who received the extract, and suggested that the herb extended patients’ lives by 4 months during the first 18 months of the study.

Other Vitamins and Supplements. A wide variety of other vitamins (thiamin, B6, and C), minerals (calcium, magnesium, zinc, manganese, copper, selenium), nutritional supplements (carnitine, creatine), and herbal remedies (hawthorn) have been proposed as treatments for heart failure. None have been adequately tested. There is no evidence that a particular vitamin or supplement can cure heart failure. In any case, vitamins are best consumed through the food sources contained in a healthy diet.

Generally, manufacturers of herbal remedies and dietary supplements do not need FDA approval to sell their products. Just like a drug, herbs and supplements can affect the body's chemistry, and therefore have the potential to produce side effects that may be harmful. There have been several reported cases of serious and even lethal side effects from herbal products. Always check with your doctor before using any herbal remedies or dietary supplements.

Resources

www.nhlbi.nih.gov -- National Heart, Lung, and Blood Institute
www.americanheart.org -- American Heart Association
www.acc.org -- American College of Cardiology
www.hfsa.org -- Heart Failure Society of America
www.heartfailure.org -- Heart Failure Online
www.unos.org -- United Network for Organ Sharing
www.organdonor.org -- National Transplant Society
www.organdonor.gov -- US government organ donor site

References

Ahmed A, Rich MW, Fleg JL, Zile MR, Young JB, Kitzman DW, et al. Effects of digoxin on morbidity and mortality in diastolic heart failure: the ancillary digitalis investigation group trial. Circulation. 2006 Aug 1;114(5):397-403.

Battaglia M, Pewsner D, Juni P, Egger M, Bucher HC, Bachmann LM. Accuracy of B-type natriuretic peptide tests to exclude congestive heart failure: systematic review of test accuracy studies. Arch Intern Med. 2006 May 22;166(10):1073-80.

Bhatia RS, Tu JV, Lee DS, Austin PC, Fang J, Haouzi A, et al. Outcome of heart failure with preserved ejection fraction in a population-based study. N Engl J Med. 2006 Jul 20;355(3):260-9.

Birks EJ, Tansley PD, Hardy J, George RS, Bowles CT, Burke M, et al. Left ventricular assist device and drug therapy for the reversal of heart failure. N Engl J Med. 2006 Nov 2;355(18):1873-84.

Bryson CL, Mukamal KJ, Mittleman MA, Fried LP, Hirsch CH, Kitzman DW, et al. The association of alcohol consumption and incident heart failure: the Cardiovascular Health Study. J Am Coll Cardiol. 2006 Jul 18;48(2):305-11.

Bursi F, Weston SA, Redfield MM, Jacobsen SJ, Pakhomov S, Nkomo VT, et al. Systolic and diastolic heart failure in the community. JAMA. 2006 Nov 8;296(18):2209-16.

Carlson MD, Wilkoff BL, Maisel WH, Carlson MD, Ellenbogen KA, Saxon LA, et al. Recommendations from the Heart Rhythm Society Task Force on Device Performance Policies and Guidelines Endorsed by the American College of Cardiology Foundation (ACCF) and the American Heart Association (AHA) and the International Coalition of Pacing and Electrophysiology Organizations (COPE). Heart Rhythm. 2006 Oct;3(10):1250-73.

Davis BR, Piller LB, Cutler JA, Furberg C, Dunn K, Franklin S, et al. Role of diuretics in the prevention of heart failure: the Antihypertensive andLipid-Lowering Treatment to Prevent Heart Attack Trial. Circulation. 2006 May 9;113(18):2201-10. Epub 2006 May 1.

Gheorghiade M, Abraham WT, Albert NM, Greenberg BH, O'Connor CM, She L, et al. Systolic blood pressure at admission, clinical characteristics, and outcomes inpatients hospitalized with acute heart failure. JAMA. 2006 Nov 8;296(18):2217-26.

Gheorghiade M, Konstam MA, Burnett JC Jr, Grinfeld L, Maggioni AP, Swedberg K, et al. Short-term clinical effects of tolvaptan, an oral vasopressin antagonist, in patients hospitalized for heartfFailure: the EVEREST clinical status trials. JAMA. 2007 Mar 25; [Epub ahead of print]

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Hildebrandt P. Systolic and nonsystolic heart failure: equally serious threats. JAMA. 2006 Nov 8;296(18):2259-60.

Konstam MA, Gheorghiade M, Burnett JC Jr, Grinfeld L, Maggioni AP, Swedberg K, et al. Effects of oral tolvaptan in patients hospitalized for worsening heart failure: the EVEREST Outcome Trial. JAMA. 2007 Mar 25; [Epub ahead of print]

Lee DS, Pencina MJ, Benjamin EJ, Wang TJ, Levy D, O'Donnell CJ, et al. Association of parental heart failure with risk of heart failure in offspring. N Engl J Med. 2006 Jul 13;355(2):138-47.Maisel WH. Pacemaker and ICD generator reliability: meta-analysis of device registries. JAMA. 2006 Apr 26;295(16):1929-34.

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Review Date:
4/11/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

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

Agency for Healthcare Research and Quality. Effectiveness and Safety of Vitamin D in Relation to Bone Health, Structured Abstract. August 2007. Rockville, MD.

Bilezikian JP. Osteonecrosis of the jaw -- do bisphosphonates pose a risk? N Engl J Med. 2006 Nov 30;355(22):2278-81.

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

Osteoporosis

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

Overview

Signs and Symptoms
What Causes It?
Risk Factors
Preventive Care
What to Expect at Your Provider's Office
Treatment Options
Special Considerations
Supporting Research

HEALTH GUIDE REFERENCE FROM A.D.A.M

Osteoporosis, which means "porous bone," is a disease in which the bones gradually become weak and brittle. That often results in fractures -- especially of the hip, wrist, and spine -- even from simple activities like lifting a chair or bending over. According to the National Institutes of Health (NIH), about 10 million Americans have osteoporosis, while another 18 million have low bone mass and are at an increased risk for the disease. Osteoporosis is common among the elderly, but the disease can strike at any age. Although it is more common in older women, men can also have the disease.

Osteoporosis is a potentially crippling disease. The latest estimates from the NIH indicate that osteoporosis is responsible for more than 1.5 million fractures annually. Fortunately, most Americans can avoid osteoporosis altogether by eating well-balanced diet, exercising regularly, and living a healthy lifestyle.

Signs and Symptoms

Osteoporosis is sometimes considered a "silent disease" because bone loss can occur without symptoms. In fact, many people may not know they have the disease until they break a bone. Osteoporosis can also cause a vertebra (one of the 33 bony segments that form the spine) to collapse. Signs of a collapsed vertebra include:

Back pain
Loss of height
Kyphosis -- curvature of the spine that causes a humplike deformity

What Causes It?

How strong and dense your bones are results in part from the amount of calcium and other minerals they contain. Your body is constantly making new bone and breaking down (reabsorbing) old bone. When you are young, this process happens quickly, and you make more bone than you lose, so you build bone mass. After your mid-30s, your body continues to make new bone, but more slowly, so that you lose more bone than you make. The amount of bone you have in your 30s helps determine your risk of developing osteoporosis later. For women, bone loss increases significantly at menopause, when estrogen levels drop.

Other than age and menopause, causes of osteoporosis can include:

Long-term use of certain medications, particularly corticosteroids and thyroid medications (see Warnings and Precautions section)
Cushing's syndrome (when the adrenal glands produce too much of a hormone called cortisol)
Kidney failure
Diseases of the thyroid or adrenal glands
Deficiencies in calcium, vitamin D, vitamin A, vitamin K, and magnesium (however, high intake of vitamin A may actually increase the risk of osteoporosis)
Anorexia nervosa
Alcoholism
Rheumatoid arthritis

Risk Factors

Being female
Being older -- after age 75, the risk is the same for men and women
Being of European or Asian ancestry
Living a sedentary lifestyle
Being very thin
Family history of osteoporosis
Late onset of menstruation or early menopause
Smoking cigarettes, drinking too much caffeine, or drinking alcohol regularly
Diet low in calcium or high in sodium
Long-term use of certain medications, including corticosteroids, diuretics, and thyroid medications
Depression

Preventive Care

Osteoporosis can be prevented. Because your body builds bone mass until you are in your 30s, prevention should start early. Making sure you get enough calcium and vitamin D (required for your body to use calcium) is essential.

Weight-bearing exercise, such as walking or lifting weights, as well as other exercises, including tai chi, can also help stave off the disease. Research has shown that exercise early in life boosts bone mass, while exercise later in life helps to maintain bone mass. Exercise also increases strength, coordination and balance -- important tools to help prevent falls that cause fractures, especially in the elderly.

Other techniques for prevention include:

Adding soy to your diet.
Quitting smoking.
Limiting caffeine to about three cups of coffee a day.
For women, hormone replacement therapy (hormone replacement therapy has significant side effects, including increased risk of breast cancer, blood clots, and heart disease).

What to Expect at Your Provider's Office

If your doctor believes you are at risk for osteoporosis, the doctor often recommends a bone mineral density test (BMD) to determine your bone mass. This test is painless, noninvasive, and safe. It typically measures bone density in the spine, wrist, and hip (the most common sites of fractures due to osteoporosis), while others measure bone in the heel or hand.

The National Osteoporosis Foundation recommends a BMD for women who are not taking estrogen and:

Use any medications that put you at risk for osteoporosis
Had an early menopause
Have a family history of osteoporosis, kidney disease, liver disease, or type 1 diabetes
Are over 50, postmenopausal, with at least one risk factor for osteoporosis
Are over 65 and have never had a BMD

Treatment Options

For those who are at risk for osteoporosis or already have the disease, current treatments are designed to boost bone mass and prevent (further) bone loss. While calcium by itself doesn't cure or prevent osteoporosis, getting enough calcium is an essential part of any prevention or treatment program. Making lifestyle choices, such as consuming a diet rich in fruits and vegetables and participating in a weight-bearing exercise program can also enhance bone strength.

Lifestyle

Diet

Studies suggest that diets rich in the following foods and nutrients may help prevent bone loss in both men and women:

Calcium -- Low-fat milk, cheese, and broccoli are rich in calcium. Orange juice and cereals often are fortified with calcium
Magnesium -- Avocado, banana, cantaloupe, honeydew, lima beans, low-fat milk, nectarine, orange juice, potato, spinach
Potassium -- Whole grains, nuts, spinach, oatmeal, potato, peanut butter
Vitamin D -- The body makes vitamin D after exposure to sunlight. It is also found in fatty fish and fortified cereals and milk
Vitamin K -- Leafy greens, cauliflower
Fruits
Vegetables

Exercise

Exercise can help prevent bone loss. Although it is helpful to begin exercising when you are young (to help build bone), it's never too late to get the benefit. Weight-bearing exercise (walking, weight-lifting) stimulates bones to produce more cells, slowing bone loss. Exercise also improves balance, flexibility, strength, and coordination -- thereby reducing falls and fractures associated with osteoporosis.

Drug Therapies

Although the standard treatment for osteoporosis for postmenopausal women used to be estrogen, there are new options for men and for women who are wary of estrogen's risks. Most medications slow down the rate at which bone is reabsorbed (antiresorptive). One new drug can actually help the body make new bone (bone forming).

Estrogens (with or without progesterone) -- boosts bone density and reduces the risk of fracture by slowing bone loss, boosting the body's ability to absorb calcium, and reducing the amount of calcium excreted in the urine. Estrogen by itself can increase a woman's risk for developing cancer in her uterine lining (endometrial cancer), so many doctors have prescribed a combination of estrogen and progesterone. However, evidence now shows that this combination increases a woman's risk of breast cancer and heart disease. Talk with your doctor to get a clear understanding of the risks and benefits of taking estrogen.
Alendronate (Fosamax), ibandronate (Boniva), and risedronate (Actonel) -- these medications belong to a class of drugs known as bisphosphonates. These drugs have been shown to boost bone density, slow or stop bone loss, and reduce the risk of fractures. Side effects are uncommon but may include abdominal pain and heartburn, which can be reduced by taking the medications with 8 oz. of water first thing in the morning before eating anything else, and standing upright for at least 30 minutes after taking them.
Raloxifene (Evista) -- from a class of drugs called Selective Estrogen Receptor Modifiers (SERMS), raloxifene has estrogen-like effects on bone (it prevents bone loss) but does not increase the risk for breast cancer. Side effects can include hot flashes and blood clots. It should not be used before menopause.
Calcitonin (Miacalcin) -- Does not improve bone density as well as the bisphosphonates, but it does slow bone loss, reduce spinal fractures, and ease pain associated with bone fractures. An alternative for women who cannot take estrogen or bisphosphonates.
Parathyroid hormone (Forteo) -- used in low doses, this drug can increase bone production. It can only be taken by injection. It is often prescribed for postmenopausal women and men at risk of fracture. It should not be used in children.

Surgery and Other Procedures

A procedure called kyphoplasty can be used to treat kyphosis, the humplike deformity sometimes caused by osteoporosis. A catheter inserts a balloon into the middle of a collapsed vertebra and then expanded so that height of the vertebra is restored. The surgeon then injects bone cement into the vertebra to hold its shape.

Complementary and Alternative Therapies

Nutrition and Supplements

Eating fruits and vegetables and consuming adequate amounts of calcium and vitamin D are crucial in the prevention and treatment of osteoporosis. Keeping bones healthy throughout life depends on getting enough of specific vitamins and minerals, including phosphorous, magnesium, boron, manganese, copper, zinc, folate, and vitamins B12, B6, C, and K. Avoiding sodium, alcohol, and caffeine will also enhance bone health.

Calcium -- Calcium helps the body build bone. Recommended intakes of calcium are as follows (note that you generally get from 500 - 700 mg of calcium in your diet):

Children: 800 - 1,200 mg/day
Adolescent girls: 1,200 - 1,500 mg/day
Premenopausal women (19 - 50 years old): 1,000 mg/day
Older adults (51 - 70 years old): 1,200 - 1,500 mg/day

(Recommended intake for older women is 1,500 mg/day, except for those on estrogen, who need only 1,000 mg/day.)

Good dietary sources of calcium include:

Low-fat dairy products (such as milk, yogurt, and cheese)
Dark green, leafy vegetables (such as broccoli, collard greens, and spinach)
Salmon
Tofu
Almonds

If you do not get enough calcium from food alone, you may want to take a calcium supplement. There are several different kinds available. Ask your doctor which one is right for you:

Calcium citrate (Citrical, Solgar) -- Most easily absorbed; costs more
Calcium carbonate (Tums, Caltrate, Rolaids) -- least expensive; must be taken with meals or a glass of orange (acidic) juice; may cause gas or constipation
Calcium phosphate (Posture) -- Easily absorbed, does not cause stomach upset; more expensive than calcium carbonate

Calcium supplements should be taken in divided doses during the day, because your body can only absorb 500 mg or calcium at a time. Work with your doctor make sure you get enough, but not too much, calcium.

Vitamin D -- In order to absorb enough calcium, your body also needs vitamin D. Recommended intakes of vitamin D are as follows:

Older adults (51 - 70 years old): 400 IU/day; (71 years and older): 600 IU/day

During the winter, or in the case of a bone fracture, 800 IU/day may be required. Doses greater than 1,000 IU can be dangerous.

Vitamin K (150 - 500 mcg) -- Vitamin K, which the body makes in the intestine, helps bind calcium into bone. A recent study suggests that at menopause, vitamin K may start to lose its ability to bind calcium, so that even women with normal levels of vitamin K may not have enough to maintain bone health. Eating three servings of low-fat dairy or dark, leafy greens per day can help. Talk to your doctor about whether you need a supplement, especially if you take blood-thinning medications (diuretics).

Soy isoflavones -- Isoflavones are phytoestrogens, plant chemicals that have some of the same effects as estrogen. Because estrogen helps protect against osteoporosis, researchers theorize that isoflavones may also help stop bone loss. Several studies seem to agree. The best source of soy isoflavones is through your diet (tofu, soy milk, soybeans); when isoflavones are consumed in foods, they don't appear to have the same negative effects that supplemental estrogen does. If you have a history of hormone-related cancer, talk to your doctor before taking soy.

Ipriflavone (600 mg per day) -- Ipriflavone, a synthetic isoflavone derived from natural isoflavones found in soy, red clover, and other food sources, may also help prevent and treat osteoporosis. Most studies -- though not all -- indicate that ipriflavone, when combined with calcium, can slow bone loss and help prevent fractures of the vertebrae (spine) in postmenopausal women. Talk to your doctor before taking ipriflavone.

Fish oil (4 g per day) -- A few studies have shown that supplements containing essential fatty acids, such as those found in fish oil, can help maintain or possibly increase bone mass. Essential fatty acids appear to increase the amount of calcium absorbed your body, diminish the amount of calcium lost in urine, improve bone strength, and enhance bone growth. Foods rich in essential fatty acids (including coldwater fish such as salmon) can help raise the amount of essential fatty acids in your diet. People who are taking blood-thinning medication (anticoagulants) should not take fish oil supplements without talking to their doctor first.

Preliminary studies also suggest that the following nutrients may help prevent or treat osteoporosis:

Zinc -- stimulates bone formation and inhibits bone loss in animals.
Vitamin C -- may limit bone loss in early years of menopause. Studies show mixed results.
Melatonin -- melatonin is involved in bone growth. Since levels of melatonin drop as you age, it's possible that melatonin may contribute to the development of osteoporosis, but further studies are needed. People who take antidepressants or psychiatric medications should not take melatonin without a doctor's supervision.

See the Warnings and Precautions section for a list of supplements that people with osteoporosis should avoid.

Herbs

Although most herbs have not been studied extensively for the treatment of osteoporosis, some have estrogen-like effects that might offer similar protection against osteoporosis. However, they may also carry some of the same risks as supplemental estrogen. Talk to your doctor before taking any of these herbs.

Black cohosh (Cimicifuga racemosa) -- contains phytoestrogens (estrogen-like substances that help protect against bone loss). It os often used to relieve menopausal symptoms, although evidence for its effectiveness is mixed. It does not appear to increase the risk of breast cancer the way supplemental estrogen does.
Red clover (Trifolium pratense) -- isoflavones extracted from this herb may slow bone loss in women, but it is not clear whether the whole herb has similar effects. More tests are needed to prove its effectiveness.

Other herbs that may help prevent or treat osteoporosis (evidence is lacking so far) include:

Horsetail (Equisetum arvense) -- contains silicon, believed to strengthen bone
Kelp (Fucus vesiculosus L.) -- used for musculoskeletal disorders; rich in minerals so may be an effective complementary treatment for osteoporosis
Oat straw (Avena sativa) -- boosts hormone levels that stimulate cell growth

Special Considerations

Warnings and Precautions

Some studies suggest that too much vitamin A may increase the risk for osteoporosis. People with osteoporosis, or those at risk for it, should not exceed the daily recommended intake of vitamin A (900 mcg/day for men and 700 mcg/day for women).

Certain medications may contribute to the development of osteoporosis when used for long periods of time:

Corticosteroids (steroid hormones)
Thyroid medications
Blood-thinners
Diuretics (water pills)
Antibiotics
Immune system suppressants
Aluminum-containing antacids

Talk to your doctor if you take any of these medications.

Prognosis and Complications

Bone fractures are the most common complications of osteoporosis and are a significant cause of disability and death. After age 60, 25% of women have a spinal fracture -- and that percentage doubles after age 75. By age 90, 33% of women and 17% of men have had a hip fracture, usually from a minor fall or accident. Many elderly people who suffer a hip fracture lose the ability to walk and, most significantly, up to 36% die within one year.

Although an estimated 1.5 million bone fractures in the U.S. each year result from osteoporosis, most of these fractures are preventable. Several medications are currently being researched that may expand the treatment options available to people with osteoporosis. In the meantime, a combination of medications, diet, exercise, and calcium and vitamin D supplements can help slow the progression of the disease.

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Review Date:
3/19/2007
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

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Healthy Eating Tip: Eat Five Colors a Day

FitSugar — Wed, 18 Mar 2009 08:00:00 -0700

We are more than halfway through March, which is also National Nutrition Month, so hopefully, you all are working hard to eat at least five servings of fruits and veggies daily. Well, I am going to up the ante: Try to eat five different colors fruits and veggies daily.

It is important to eat a rainbow since disease fighting antioxidants also give foods their color. The wider color palate you eat the wider the spectrum of antioxidants, vitamins, and minerals you will be eating. Yep, downing just goji berries or drinking pomegranate juice is really not enough to be considered healthy eating.

To see how I have worked five colors into my meals, read more.

Breakfast: Blue - I throw a half of cup of frozen blueberries onto my morning oatmeal, and while the oatmeal cools the berries thaw.
Snack: Yellow - I like a little tropical fruit salad to get me through until lunch and mix sliced banana with sliced mango.
Lunch: Green - Spinach and arugula salad surely covers me for green.
Dinner: Orange - Roasted yams certainly cover the color orange.
Dessert: Red - Strawberries are at the beginning of their season and sliced or whole they make a wonderful dessert.

It is super easy to add a variety of color to your daily diet, but might require a little planning ahead and thinking back. You can substitute purple cabbage for green, red pepper for green, broccoli for cauliflower, yams for regular spuds . . . you get the point. Tell me below how you work color into your daily diet?

Source

Get the Bod: Jessica Biel's Workout

FitSugar — Mon, 06 Apr 2009 14:30:00 -0700

When I think of fit celebs, Jessica Biel definitely comes to mind. Her toned tush and defined arms are the reason she's won the title of Fitsugar's Fittest Female Celeb two years in a row. If you want to know how she maintains such a strong and feminine physique, her personal trainer Jason Walsh told People magazine about her workouts. Here's what he said:

Stretch: Jessica warms up with walking lunges. Jason says, "This stretches the larger leg and glute muscles.”
Cardio: She hits the track and jogs for half a mile, then does two 200-meter, 150-meter, and 100-meter sprints. This type of cardio interval training "leans her out," Jason says.
Core: “Hanging leg raises don’t build a six-pack, but they flatten,” says Walsh. “Jessica hates them, but she powers through!”

To find out what else Jason Walsh had to say read more.

Plyometrics: “These hurt,” says Walsh of stair jumping. “Even athletes hate them. After Jessica did these the first time, she would’ve punched me if she had the energy.”
Weight Training: Jason says, “We tend to use lighter weights and do more reps. We keep moving, so it becomes a cardio workout, too.”
Waist: Get ready for Seated Russian Twists. Jessica does them holding a five-pound medicine ball. Twist to each side 15 times, and do a total of three sets.
Shoulders and biceps: Stand with knees slightly bent. Hold 10-pound dumbbells in each hand. Do a bicep curl and then rotate your hands hands so your palms face outward, and do a Twisting Dumbbell Press. Then reverse the move until you're back to the starting position. Complete three sets of 10 to 12 reps.

As for her diet, Jessica eats complex carbohydrates such as oatmeal and whole wheat toast with one tablespoon of almond butter in the morning. For dinner she enjoys fish, veggies, and basmati rice. She snacks on fruits like bananas, apples, and strawberries. She doesn't deny herself the foods she craves, and likes to treat herself at the end of the day with something sweet like a piece of dark chocolate.

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