FitSugar

Pom Poms for Pomegranates

FitSugar — Tue, 16 Oct 2007 11:45:00 -0700

I will wholeheartedly become a cheerleader when it comes to pomegranates. Not only does this fruit make a great decorative centerpiece on your table, it is full of tasty little seeds that can add a little zing to many dishes. Although the flavor is considered tart, the pomegranate crosses the line of savory and sweet. Nutritionally speaking, the beautiful garnet colored juicy seeds inside are high in antioxidants that not only protect your blood lipids from the nasty act oxidation; they also help prevent plaque build up on arteries. Pomegranates are also a great source of potassium.

I feel the most timely pomegranate fact is they are in season now. The seeds make a great addition to any fall salad and are tasty scattered over roasted squash. The juice of the fruit makes a fine addition to any cocktail too. Just beware the beautiful juice can stain, not only your hands but your clothes too.

Confused about how to reach those powerful little seeds? Don't worry because my gal Yum can teach you. Just read How to Seed a Pomegranate.

Do you like pomegranates? Tell me your favorite way to eat them in the comment section below.

Source

Learn to Love: Persimmons

FitSugar — Mon, 23 Nov 2009 08:00:01 -0800

Now that berry season is long gone, I'm expanding my breakfast fruit horizons. Celebrate the cold weather with pomegranate seeds in your oatmeal, or slice pears or persimmons and serve them with nut butter on toast or whole-grain waffles.

You probably know how to pick and slice a pear, but persimmons have a steeper learning curve. They're worth learning to love, so read more.

Persimmons come in two varieties: hachiya, which are orange-red and shaped like acorns, and fuyu, which sort of look like yellow-orange tomatoes. The hachiyas are bitter and astringent when they're not ripe, but when ripened, they have a soft, jelly-like texture. Fuyu persimmons are a bit firmer like a pear when ripe and can be sliced up like apples.

This fruit is an excellent source of antioxidants and chock-full of vitamins. One persimmon packs 55 percent of your daily allowance of Vitamin A and 21 percent of your recommended Vitamin C, plus six grams of fiber. In addition to having persimmon for breakfast or a snack, you can slice them up and serve them in a pretty Fall salad.

Have you tried persimmons? Tell me how you like to eat them in the comments.

Health Benefits of Pears

FitSugar — Thu, 22 Oct 2009 09:00:13 -0700

Apples are in season in the Autumn, but pears are too. The soft, sweet, buttery flesh of the pear makes this Fall fruit one of my favorites. Plus there are so many varieties to choose from - Bartlett, Bosc, and Anjou - that they each seem like a different fruit. These juicy gems are pretty healthy for you, too.

Pears are high in fiber. One medium-sized pear contains six grams, so snacking on a pear can help you meet your daily requirement of 25 to 30 grams. They're a delicious way to keep you regular too, which can help prevent colon cancer. A diet high in fiber can also keep your cholesterol levels down, which is good news for your ticker. Getting your fill of fiber from fruit is also linked to a lower risk for breast cancer.
Pears contain a fair amount of vitamins A, C, K, B2, B3, and B6. For expecting or nursing moms, they also contain folate. Pears aren't too shabby in the mineral department either, containing calcium, magnesium, potassium, copper, and manganese. Vitamin C and copper are antioxidant nutrients, so eating pears is good for your immune system, and may help prevent cancer.
Pears also contain boron, which our bodies need in order to retain calcium, so this fruit can also be linked to osteoporosis prevention.

For the other health benefits, read more.

The hydroxycinnamic acid found in pears is also associated with preventing stomach and lung cancer.
It's a hypo-allergenic fruit. That means those with food sensitivities can usually eat pears with no adverse effects.
Eating three or more servings of fruits a day, such as pears, may also lower your risk of age-related macular degeneration (ARMD), the primary cause of vision loss in older adults.
Quercetin is another antioxidant found in the skin of pears. It helps prevent cancer and artery damage that can lead to heart problems. A recent study at Cornell University found it may also protect against Alzheimer’s disease. So don't peel your pears!

Tell me, what's your favorite type of pear?

Can You Identify the Produce?

FitSugar — Wed, 21 Oct 2009 05:50:11 -0700

We are all striving for five daily servings of fruits and veggies. Fresh produce can be difficult to identify, but knowing what's what is key to a healthy diet. I'm curious how well you know your Fall produce. Take this little quiz and see if you can identify different types of seasonal fruits and veggies available in grocery stores right now.

Question 1 of 7

What is the name of this Fall fruit?

Diabetes diet

FitSugar — Wed, 08 Oct 2008 17:35:01 -0700

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Lifestyle Changes Essential for People at Risk for Diabetes

Lifestyle interventions that include weight loss, dietary changes, and increased physical activity can definitely help prevent or delay the progression to diabetes among at-risk people, suggest several recent studies. Weight loss through diet and exercise is especially important for overweight people with pre-diabetes.

Grain Fiber Important for Diabetes Prevention

Eating whole-grain, fiber-rich, cereal foods may help reduce the risk of developing type 2 diabetes, indicates a 2007 study in the Archives of Internal Medicine. In the study, people who consumed the most fiber from grains and cereals had a 33% lower risk of developing diabetes than people with the lowest fiber intakes. The study also found an association between high magnesium intake and reduced diabetes risk. Although fruits and vegetables also contain fiber, they did not appear to affect diabetes risk.

Low-Fat Dairy Products

Incorporating low-fat dairy products (such as yogurt and milk) into a healthy diet may help reduce diabetes risk for women, suggests a study in Diabetes Care.

Beware of Internet Dietary Supplement Scams

In 2006, the FDA alerted consumers not to be misled by dietary supplements advertised on the Internet as treatments or cures for diabetes. These products have not been scientifically studied or approved.

Low-Glycemic Index Diets

Food low on the glycemic index -- such as whole grains, fruits, lentils, and soybeans -- can help promote weight loss and heart health. Illustrating the complexity of this area, a 2006 study in the New England Journal of Medicine indicated that a low-carb, low-glycemic index diet was beneficial while another study in the Archives of Internal Medicine suggested advantages for a high-carb, low-glycemic index diet.

Low-Fat Vegan Diets

A low-fat diet that excludes meat and dairy products may help improve glycemic control and increase insulin sensitivity, suggests a Diabetes Care study. Researchers think that the high fiber content of these diets, in addition to their reduced fat, may be a factor.

Introduction

The two major forms of diabetes are type 1, previously called insulin-dependent diabetes mellitus (IDDM) or juvenile-onset diabetes, and type 2, previously called non-insulin-dependent diabetes mellitus (NIDDM) or maturity-onset diabetes. [See In-Depth Report #9: Diabetes - type 1 and In-Depth Report #60: Diabetes - type 2.]

Both type 1 and type 2 diabetes share one central feature: elevated blood sugar (glucose) levels due to absolute or relative insufficiencies of insulin, a hormone produced by the pancreas. Insulin is a key regulator of the body's metabolism. It normally works in the following way:

During and immediately after a meal the process of digestion breaks carbohydrates down into sugar molecules (of which glucose is one) and proteins into amino acids.
Right after the meal, glucose and amino acids are absorbed directly into the bloodstream, and blood glucose levels rise sharply. (Glucose levels after a meal are called postprandial levels.)
The rise in blood glucose levels signals important cells in the pancreas, called beta cells, to secrete insulin, which pours into the bloodstream. Within 10 minutes after a meal insulin rises to its peak level.
Insulin then enables glucose and amino acids to enter cells in the body, particularly muscle and liver cells. Here, insulin and other hormones direct whether these nutrients will be burned for energy or stored for future use. (The brain and nervous system are not dependent on insulin; they regulate their glucose needs through other mechanisms.)
When insulin levels are high, the liver stops producing glucose and stores it in other forms until the body needs it again.
As blood glucose levels reach their peak, the pancreas reduces the production of insulin.
About 2 - 4 hours after a meal both blood glucose and insulin are at low levels, with insulin being slightly higher. The blood glucose levels are then referred to as fasting blood glucose concentrations.

Click the icon to see an image of the liver.

In type 1 diabetes, the disease process is more severe than with type 2, and onset usually begins in childhood:

Beta cells in the pancreas that produce insulin are gradually destroyed. Eventually insulin deficiency is absolute.
Without insulin to move glucose into cells, blood glucose levels become excessively high, a condition known as hyperglycemia.
Because the body cannot utilize the sugar, it spills over into the urine and is lost.
Weakness, weight loss, and excessive hunger and thirst are among the consequences of this "starvation in the midst of plenty."

Click the icon to see an image of the pancreas.

Patients with type 1 diabetes need to take insulin. Dietary control in type 1 diabetes is very important and focuses on balancing food intake with insulin intake and energy expenditure from physical exertion. [See In-Depth Report #9: Diabetes - type 1.]

Type 2 diabetes is the most common form of diabetes, accounting for up to 95% of all diabetes cases. About 20 million Americans have type 2 diabetes, and half are unaware they have it. The disease mechanisms in type 2 diabetes are not wholly known, but some experts suggest that the disease may involve the following three stages in most patients:

The first stage in type 2 diabetes is the condition called insulin resistance. Although insulin can attach normally to receptors on liver and muscle cells, certain mechanisms prevent insulin from moving glucose (blood sugar) into these cells where it can be used. Most patients with type 2 diabetes produce variable, even normal or high, amounts of insulin, and in the beginning this amount is usually sufficient to overcome such resistance. Patients whose blood glucose levels are higher than normal, but not yet high enough to be classified as diabetes, are considered to have “pre-diabetes.” It is very important that people with pre-diabetes control their weight to stop or delay the progression to diabetes.
Over time, the pancreas becomes unable to produce enough insulin to overcome resistance. In type 2 diabetes, the initial effect of this stage is usually an abnormal rise in blood sugar right after a meal (called postprandial hyperglycemia). This effect is now believed to be particularly damaging to the body.
Eventually, the cycle of elevated glucose further impairs and possibly destroys beta cells, thereby stopping insulin production completely and causing full-blown diabetes. This is made evident by fasting hyperglycemia, in which elevated glucose levels are present most of the time.

Obesity is common in patients with type 2 diabetes and this condition appears to be related to insulin resistance. The primary dietary goal for overweight type 2 patients is weight loss and maintenance. Studies indicate that when people with type 2 diabetes maintain intensive exercise and diet modification programs, many can minimize or even avoid medications. Weight loss medications or bariatric surgery may be appropriate for some patients. [See In-Depth Report #60: Diabetes - type 2 and In-Depth Report #53: Weight control and diet.]

General Dietary Guidelines

For people who have pre-diabetes, or who are at high risk of developing type 2 diabetes, lifestyle changes of diet and exercise are extremely important. Several studies have shown that lifestyle interventions are very effective in preventing or postponing the progression to diabetes. These interventions are especially important for overweight people -- even moderate weight loss can help reduce diabetes risk.

The American Diabetes Association recommends that people at high risk for type 2 diabetes eat high-fiber (14g fiber for every 1,000 calories) and whole-grain foods. A 2007 study in the Archives of Internal Medicine also suggested that high intake of fiber and magnesium, especially from whole grain cereals and breads, can help reduce type 2 diabetes risk.

For people who have diabetes, the treatment goals for a diabetes diet are:

Achieve near normal blood glucose levels. People with type 1 diabetes and people with type 2 diabetes who are taking insulin or oral medication must coordinate calorie intake with medication or insulin administration, exercise, and other variables to control blood glucose levels. New forms of insulin are now allowing more flexibility in timing meals.
Protect the heart and aim for healthy lipid (cholesterol and triglyceride) levels and control of blood pressure.
Achieve reasonable weight. Overweight patients with type 2 diabetes who are not taking medication should aim for a diet that controls both weight and glucose. A reasonable weight is usually defined as what is achievable and sustainable, rather than one that is culturally defined as desirable or ideal. Children, pregnant women, and people recovering from illness should be sure to maintain adequate calories for health.
Manage or prevent complications of diabetes. People with diabetes, whether type 1 or 2, are at risk for a number of medical complications, including heart and kidney disease. Dietary requirements for diabetes must take these disorders into consideration.
Promote overall health.

Overall Guidelines. Overall Guidelines. There is no such thing as a single diabetes diet. Patients should meet with a professional dietitian to plan an individualized diet within the general guidelines that takes into consideration their own health needs.

For example, a patient with type 2 diabetes who is overweight and insulin-resistant may need to have a different carbohydrate-protein balance than a thin patient with type 1 diabetes in danger of kidney disease. Because regulating diabetes is an individual situation, everyone with this condition should get help from a dietary professional in selecting the best method.

Healthy eating habits along with good control of blood glucose are the basic goals in managing this complex disease, and several good dietary methods are available to meet them. General dietary guidelines for diabetes recommend:

Carbohydrates should provide 45 - 65% of total daily calories. The type and amount of carbohydrate are both important. Best choices are vegetables, fruits, beans, and whole grains. These foods are also high in fiber. Patients with diabetes should monitor their carbohydrate intake either through carbohydrate counting or meal planning exchange lists.
Fats should provide 25 - 35% of daily calories. Monounsaturated (olive, peanut, canola oils; avocados; nuts) and omega-3 polyunsaturated (fish, flaxseed oil, walnuts) fats are the best types. Limit saturated fat (red meat, butter) to less than 7% of daily calories. Choose nonfat or low-fat dairy instead of whole milk products. Limit trans-fats (hydrogenated fat found in snack foods, fried foods, commercially baked goods) to less than 1% of total calories.
Protein should provide 12 - 20% of daily calories, although this may vary depending on a patient’s individual health requirements. Patients with kidney disease should limit protein intake to less than 10% of calories. Fish, soy, and poultry are better protein choices than red meat.
Lose weight if body mass index (BMI) is 25 - 29 (overweight) or higher (obese).

Several different dietary methods are available for controlling blood sugar in type 1 and insulin-dependent type 2 diabetes:

Diabetic Exchange Lists (for maintaining a proper balance of carbohydrates, fats, and proteins throughout the day)
Carbohydrate Counting (for tracking the number of grams of carbohydrates consumed each day)
Glycemic index (for tracking which carbohydrate foods increase blood sugar)

Tests for Glucose Levels. Both low blood sugar (hypoglycemia) and high blood sugar (hyperglycemia) are of concern for patients who take insulin. It is important, therefore, to monitor blood glucose levels carefully. Patients should aim for the following measurements:

Pre-meal glucose levels of 90 - 130 mg/dL
Bedtime levels of 110 - 150 mg/dL

In general, patients who are tightly controlling glucose levels need to take readings four or more times a day. Blood glucose levels are generally more stable in type 2 diabetes than in type 1, so experts usually recommend that these patients measure blood levels only once or twice a day. Different goals may be required for specific individuals, including pregnant women, very old and very young people, and those with accompanying serious medical conditions.

Tests for Glycosylated Hemoglobin. Another test examines blood levels glycosylated hemoglobin, also known as hemoglobin A1c (HbA1c). Measuring glycosylated hemoglobin is useful for determining the severity of diabetes. The test is not affected by food intake so it can be taken at any time. A home test has been developed that may make it easier to measure HbA1c. In general, measurements suggest the following:

Normal HbA1c levels should be below 7%
Levels of 11 - 12% glycolated hemoglobin indicate poor control of carbohydrates. High levels are also markers for kidney trouble.

Other Tests. Other tests are needed periodically to determine potential complications of diabetes, such as high blood pressure, unhealthy cholesterol levels, and kidney problems. Such tests may also indicate whether current diet plans are helping the patient and whether changes should be made. Annual urine tests showing even microscopic traces of a protein known as albumin can indicate a future risk for serious kidney disease.

For prevention of long-term complications of diabetes, experts now recommend that all patients with diabetes aim at keeping blood levels as close to normal as possible. Such intensive insulin treatment can increase the risk of hypoglycemia, which occurs when blood sugar is extremely low (below 60 mg/dL). The following tips may help avoid hypoglycemia or prepare for attacks.

Patients are at highest risk for hypoglycemia at night. Bedtime snacks may be helpful.
Patients who intensively control their blood sugar should monitor blood levels as often as possible, four times or more per day. This is particularly important for patients with hypoglycemia unawareness.
In adults, it is also particularly critical to monitor blood glucose levels before driving, when hypoglycemia can be very hazardous.
Patients on therapies that put them at risk for hypoglycemia should always carry hard candy, juice, sugar packets, or commercially available glucose substitutes designed for individuals with diabetes.

Food Labels. Every year thousands of new foods are introduced, many of them advertised as nutritionally beneficial. It is important for everyone, most especially people with diabetes, to be able to differentiate advertised claims from truth. The current food labels show the number of calories from fat, the amount of nutrients that are potentially dangerous (fat, cholesterol, sodium, sugars) as well as useful nutrients (fiber, carbohydrates, protein, vitamins).

Labels also show "daily values," the percentage of a daily diet that each of the important nutrients offers in a single serving. Unfortunately, the daily value is based on 2,000 calories, generally much higher than most patients with diabetes should have, and the serving sizes may not be equivalent to those on the Exchange Lists. Most people will need to recalculate the grams and calories listed on food labels to fit their own serving sizes and calorie needs.

Weighing and Measuring. Weighing and measuring food is extremely important in order to get the correct number of daily calories.

Along with measuring cups and spoons, choose a food scale that measures grams. (A gram is very small, about 1/28th of an ounce.)
Food should be weighed and measured after cooking.
After measuring all foods for a week or so, most people can make fairly accurate estimates by eye or by holding food without having to measure everything every time they eat.

Timing. Meals should not be skipped, particularly for those who are on insulin. Skipping meals can upset the balance between food intake and insulin and also can lead to weight gain if the patient eats extra food too often to offset low blood sugar levels.

The timing of meals is particularly important for people taking insulin:

Patients should coordinate insulin administration with calorie intake. In general, they should eat three meals each day at regular intervals. Snacks are often required.
They should try to take an insulin injection 30 minutes before they eat, although this timing could vary, depending on the form. Some experts recommend a fast acting insulin (insulin lispro) at each meal and a longer (basal) insulin at night.

Diabetes can lead to kidney disease and failure. People with early-stage kidney failure need to follow a special diet that slows the build-up of wastes in the bloodstream. The diet restricts protein, potassium, phosphorus, and salt intake. Fat and carbohydrate intake may need to be increased to help maintain weight and muscle tissue.

People who have late-stage kidney disease usually need dialysis. Once patients are on dialysis, they must have more protein in their diet. Patients must still be very careful about restricting salt, potassium, phosphorus, and fluids. Patients on peritoneal dialysis may have fewer restrictions on salt, potassium, and phosphorus than those on hemodialysis.

Major Food Components

Compared to fats and protein, carbohydrates have the greatest impact on blood sugar. Both the amount and type of carbohydrate affect blood glucose. Carbohydrate types are either complex (as in starches) or simple (as in fruits and sugars). One gram of carbohydrates equals four calories. The current general recommendation is that carbohydrates should provide between 40 - 65% of the daily caloric intake. Carbohydrate intake should not fall below 130 grams/day. Most experts do not recommend low-carb diets for diabetes management or weight control.

Vegetables, fruits, whole grains, and beans are good sources of carbohydrates. Whole grain foods provide more nutritional value than pasta, white bread, and white potatoes. Brown rice is a better choice than white rice. Patients should try to consume a minimum of 20 - 35 grams of fiber daily (ideally 50 grams/day), from vegetables, fruits, whole grain cereals, breads, nuts and seeds.

Complex Carbohydrates. Complex carbohydrates found in whole grains and vegetables are preferred over carbohydrates found in starch-heavy foods, such as pastas, white-flour products, and potatoes. Most of these are high in fiber, which is important for health. Whole-grains specifically are extremely important for people with diabetes or at risk for it. [For specific benefits, see Box Whole Grains, Nuts, and Fiber-Rich Foods and Table Some Examples of Healthy Foods.]

Simple Carbohydrates (Sugar). Sugars are generally one of two types:

Sucrose (table sugar). Sucrose has been associated with higher triglycerides and harmful cholesterol levels. A 2002 study suggested that a high level of sugar consumption may also reduce levels of HDL cholesterol, the so-called good cholesterol.
Fructose (sugar found in fruits). Fructose may produce a slower increase in blood sugar than sucrose, which may have some advantages for people with diabetes. Dark-colored fruits are rich in important vitamins and other nutrients, and studies continue to report their benefits for the heart and health in general. Other fruits, such as apples and grapes also have important beneficial food chemicals.

Sugar itself, either as sucrose or fructose, adds calories, increases blood glucose levels quickly, and provides no other nutrients. High levels of sugar consumption -- both fructose and sucrose -- have been associated with higher triglycerides and lower levels of HDL cholesterol, the so-called good cholesterol. The high consumption of sugar is most likely one of the factor in the current obesity epidemic. Soda, other sweetened beverages, and fruit juice in fact may be singled out as major contributors to childhood obesity.

People with diabetes should avoid products listing more than 5 grams of sugar per serving, and some doctors recommend limiting fruit intake. If specific amounts are not listed, patients should avoid products with either sucrose or fructose listed as one of the first four ingredients on the label. [See Box Fat Substitutes and Artificial Sweeteners.]

Of increasing interest to researchers is possible harm from sugar from advanced glycation end-products (called AGEs). These are end-products of the chemical reaction between sugar and protein. This reaction occurs most intensively when cooking at high temperatures -- particularly animal fats. (Steaming or cooking food in water does not produce these chemicals. Low, slow cooking also produces fewer AGEs.) AGEs can also be formed by chemical reactions in the body itself. They may promote factors in the inflammatory response that cause a number of diseases or their complications, including diabetes and other serious conditions (Alzheimer's, atherosclerosis, cataracts, and osteoporosis).

The Carbohydrate Counting System. Some people plan their carbohydrate intake using a system called carbohydrate counting. It is based on two premises:

All carbohydrates (either from sugar or starch) will raise blood sugar to a similar degree. In general, 1 gram of carbohydrates raises blood sugar by 3 points in people who weigh 200 pounds, 4 points for people who weigh 150 pounds, and 5 points for 100 pounds.
Carbohydrates have the greatest impact on blood sugar; fats and protein play only minor roles.

In other words, the amount of carbohydrates eaten (rather than fats or proteins) will determine how high blood sugar levels will rise. There are two options for counting carbohydrates: advanced and simple. Both rely on collaboration with a doctor, dietitian, or both. Once the patient learns how to count carbohydrates and adjust insulin doses to their meals, many find it more flexible, more accurate in predicting blood sugar increases, and easier to plan meals than other systems.

The basic goal is to balance insulin with the amount of carbohydrates eaten in order to control blood glucose levels after a meal. The steps to the plan are as follows:

The patient must first carefully record a number of factors that are used to determine the specific requirements for a meal plan based on carbohydrate grams:

Multiple blood glucose readings (taken several times a day)
The time of meals
Amount in grams of all the carbohydrates eaten
Time, type, and duration of exercise
The time, type, and dose of insulin or oral medications
Other relevant factors, such as menstruation, illness, and stress

The patient works with the dietitian for two or three 45 - 90 minute sessions to plan how many grams of carbohydrates are needed. There are three carbohydrate groups:

Bread/starch
Fruit
Milk

One serving from each group should contain 12 - 15 carbohydrate grams. (Patients can find the amount of carbohydrates in foods from labels on commercial foods and from a number of books and web sites.)

The dietitian creates a meal plan that accommodates the patient's weight and needs, as determined by the patient's record, and makes a special calculation called the carbohydrate to insulin ratio. This ratio determines the number of carbohydrate grams that a patient needs to cover the daily pre-meal insulin needs.

Eventually, patients can learn to precisely adjust their insulin doses to their meals.

Patients who choose this approach must still be aware of protein and fat content in foods. These food groups may add excessive calories and saturated fats. Patients must still follow basic healthy dietary principles.

The Glycemic Index. The glycemic index helps determine which carbohydrate-containing foods raise blood glucose levels more or less quickly after a meal. The index uses a scale of numbers for specific foods that reflect greatest to least delay in producing an increase in blood sugar after a meal. The lower the index number, the better the impact on glucose levels. Some evidence suggests that the benefit of foods with a low glycemic index is due to their ability to increase insulin levels quickly and so remove blood sugar rather than their ability to slow the release of blood sugar itself.

There are currently two indices in use. One uses a scale of 1 - 100 with 100 representing a glucose tablet, which has the most rapid effect on blood sugar [See Table The Glycemic Index of Some Foods]. The other common index uses a scale with 100 representing white bread (so some foods will be above 100).

A major 2003 analysis suggested that choosing foods with a low glycemic index scores may have a small but significant effect on controlling the surge in blood sugar after meals. Many of these foods are also high in fiber and so have heart benefits as well. Substituting low- for high-glycemic index foods may also help prevent weight gain.

One easy way to improve glycemic index is to simply replace starches and sugars with whole grains and legumes (dried peas, beans, and lentils). However, there are many factors that affect the glycemic index of foods, and maintaining a diet with low glycemic load is not straightforward. The following are some considerations:

The numbers attributed to each carbohydrate-rich food cannot be added to equal a certain number. In other words, adding All Bran cereal (index of 49) to a banana (index of 61) does not equal 110.
Adding certain fats to a food (for example butter to potato) can slow down the food's impact on blood sugar. One study reported that when patients ate fatty foods first, their blood glucose levels were significantly lower an hour after the meal than when carbohydrates were eaten first.
Adding foods with organic acids (pickles, yogurt) to meals may reduce the impact of foods with high glycemic scores on blood sugar. (It should be noted that yogurt alone, however, has the same high glycemic index as regular milk.)

No one should use the glycemic index as a complete dietary guide, since it does not provide nutritional guidelines for all foods. It is simply an indication of how the metabolism will respond to certain carbohydrates. Some experts believe it is too complicated to be practical and that simply tracking carbohydrates, eating healthily, and maintaining a healthy weight is sufficient. Nevertheless, a study on children with type 1 diabetes suggested that the glycemic index offered as many choices as the exchange diet, and they did not report feeling any greater limitations. [For additional information on low-glycemic index diets, see "Heart-Healthy Diets" section of this report.]

Fiber is an important component of many complex carbohydrates. It is almost always found only in plants, (particularly vegetables), fruits, whole grains, nuts, and legumes (dried beans, peanuts, 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, legumes, and fruit and vegetable peels) may help achieve weight loss. Consuming whole grains on a regular basis appears to provide many important benefits, especially for people with type 2 diabetes. Whole grains may even lower the risk for type 2 diabetes in the first place. Of special note, nuts, such as almonds, macadamia, and walnuts may be highly heart protective, independent of their fiber content. However, nuts are high in calories.
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 reducing blood pressure as well. Evidence on the heart benefits of beans continues to grow. For example, a 2001 study indicated that eating beans four or more times a week reduced the risk for heart disease by 22%.
Soluble fiber supplements, such as those that contain psyllium or glucomannan, may be beneficial. Psyllium is taken from the husk of a seed grown in India. It is found in laxatives (Metamucil), breakfast cereals (Bran Buds), and other products. In a 2002 study, patients with type 2 diabetes who consumed psyllium (Plantaben) for breakfast for 11 weeks experienced lower total and LDL cholesterol levels. There was no difference in glucose or HbA1c levels. Psyllium can increase sodium so people who increase their levels of soluble fiber should also increase water and fluid intake.

Replacing fats and sugars with substitutes may help many people who have trouble maintaining weight. In one 2003 study, people with type 2 diabetes used the artificial sweetener sucralose and a beta-glucan fat replacer (derived from oats) as part of a low-calorie diet. At the end of 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 your diet can be harmful to general health. Some fat substitutes include:

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 their use can allow lower doses of statins (cholesterol -lowering drugs). These products do not appear to block absorption of fat-soluble nutrients or vitamins, as olestra does. They can be hydrogenated, however, and can contain some trans-fatty acids.
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. (Simply adding snacks containing olestra do not appear to have any effect on cholesterol or weight loss.) However, it can cause cramping and diarrhea. 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 adverse health effects, if any, are unknown.
Beta-glucan is a soluble fiber found in oats and barley. Products using this substance (Nu-Trim) may reduce cholesterol and have additional health benefits.

A number of other fat-replacers are also available. Although studies to date do not show any significant adverse health effects, their 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 in beverages and foods and reduced their sugar intake weighed less over time than those who ate similar types and amounts of drinks and food containing sugar. However, 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 caloric intake is under control. There is some public concern about chemicals used to produce many of these sweeteners and adverse effects in studies using rats. Natural low-calorie sweeteners that may be more acceptable to many people are also available. Low-calorie sweeteners include:

Saccharin (Sugar Twin, Sweet n’Low, Sucaryl, and Featherweight). Saccharin has been used for years but is not used as commonly now. Some studies found that large amounts of saccharin caused bladder cancer in rats. Although the rats were fed huge amounts that do not apply to human diets, some evidence suggests that people who have six or more servings of saccharin per day may have an increased risk.
Aspartame (Nutra-Sweet, Equal, NutraTase). Aspartame has come under scrutiny because of rare reports of neurologic disorders, including headaches or dizziness, associated with its use. People with phenylketonuria (PKU), a rare 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 hydroxyl atoms with chlorine atoms. 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 US since 1988 with no reported adverse 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 a novel low-calorie sweetener derived from lactose, which is found in dairy products and other foods. It may be specifically beneficial for people with type 2 diabetes and have additional benefits that aid the intestinal tract.
Alitame (Aclame) is formed from amino acids. 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 rigorously tested.

Other artificial sweeteners being investigated include, glycyrrhizin (derived from licorice), and dihycrochalcones (derived from citrus fruits).


Based on 100 = a Glucose Tablet
BREADS
pumpernickel	49
sour dough	54
rye	64
white	69
whole wheat	72
GRAINS
barley	22
sweet corn	58
brown rice	66
white rice	72
BEANS
soy	14
red lentils	27
kidney (dried and boiled, not canned)	29
chickpeas	36
baked	43
DAIRY PRODUCTS
milk	30
ice cream	60
CEREALS
oatmeal	53
All Bran	54
Swiss Muesli	60
Shredded Wheat	70
Corn Flakes	83
Puffed Rice	90
PASTA
spaghetti-protein enriched	28
spaghetti (boiled 5 minutes)	33
spaghetti (boiled 15 minutes)	44
FRUIT
strawberries	32
apple	38
orange	43
orange juice	49
banana	61
POTATOES
sweet	50
yams	54
new	58
mashed	72
instant mashed	86
white	87
SNACKS
potato chips	56
oatmeal cookies	57
corn chips	72
SUGARS
fructose	22
refined sugar	64
honey	91
Note. These numbers are general values, but may vary widely depending on other factors, including if and how they are cooked and foods they are combined with.

Protein intake in diabetes is complicated. Protein recommendations vary among experts and depend on various factors. These factors include whether a patient has type 1, type 2, or pre-diabetes. There are additional guidelines for patients who show signs of kidney damage (nephropathy).

In general, diabetes dietary guidelines recommend that proteins should provide 12 - 20% of total daily calories. This daily amount poses no risk to the kidney in people who do not have kidney disease. Protein is important for strong muscles and bone. Some experts recommend a higher proportion of protein (20 - 30%) for patients with pre- or type 2 diabetes. They think that eating more protein helps people feel more full and thus reduces overall calories. In addition, protein consumption helps the body maintain lean body mass during weight loss.

Because protein causes the kidneys to work harder, patients with diabetic nephropathy need to limit their intake of protein. A typical protein-restricted diet limits protein intake to no more than 10% of total daily calories. Patients with kidney damage also need to limit their intake of phosphorus, a mineral found in dairy products, beans, and nuts. (However, patients on dialysis need to have more protein in their diets.) Potassium and phosphorus restriction is often necessary as well.

One gram of protein contains 4 calories. Protein is commonly recommended as part of a bedtime snack to maintain normal blood sugar levels during the night, although studies are mixed over whether it adds any protective benefits against nighttime hypoglycemia. If it does, only small amounts (14 grams) may be needed to stabilize blood glucose levels.

Good sources of protein include fish, skinless chicken or turkey, nonfat or low-fat dairy products, soy (tofu), and legumes (kidney beans, black beans, chick peas, lentils).

Fish. Fish is probably the best source of protein. Evidence suggests that eating moderate amounts of fish (twice a week) may improve triglycerides and help lower the risks for death from heart disease, dangerous heart rhythms, blood pressure, a tendency for blood clots, and the risk for stroke.

The most healthy fish are oily fish such as salmon, mackerel, or sardines, which are high in omega-3 fatty acids. Three capsules of fish oil (preferably as supplements of DHA-EPA) is about equivalent to eating one serving of fish.

Some studies have reported a higher incidence of heart attack in men who ate fish daily. Such findings may be due to mercury toxicity, which has harmful effects on the heart. High mercury content has been observed in swordfish and shark and, to some extent, in tuna, trout, pike, tilapia, and bass.

Fish oil supplements may also have some adverse effects on LDL levels and glucose control in type 2 diabetes. More research is needed to further define the risk and benefits of fish, but at this time most guidelines recommend eating fish two or three times a week.

Soy. Soy is an excellent food. It is rich in both soluble and insoluble fiber, omega-3 fatty acids, and provides all essential proteins. Soy proteins have more vitamins and minerals than meat or dairy proteins. They also contain polyunsaturated fats, which are better than the saturated fat found in meat. The best sources of soy protein are soy products (tofu, soy milk, soybeans). Soy sauce is not a good source. It contains only a trace amount of soy and is very high in sodium.

For many years, soy was promoted as a food that could help lower cholesterol and improve heart disease risk factors. But an important 2006 American Heart Association (AHA) review of studies found that soy protein and isoflavone supplement pills do not really have any effects on cholesterol or heart disease prevention. The AHA still encourages patients to include soy foods as part of an overall heart healthy diet, but does not recommend using isoflavone supplements.

Meat and Poultry. Lean cuts of meat are the best choice for heart health and diabetes control. Saturated fat in meat is the primary danger to the heart. The fat content of meat varies depending on the type and cut. For patients with diabetes, experts recommend choosing skinless chicken or turkey over red meat. (Fish is an even better choice.) A large, long-term 2006 study found that high heme iron intake from red meat increases the risk of developing type 2 diabetes in women. Another 2006 study suggested that replacing red meat with chicken improves kidney function and lipid levels in patients with diabetic nephropathy.

Dairy Products. A 2002 study reported that a high intake of dairy products can lower risk factors related to type 2 diabetes and heart disease (insulin resistance, high blood pressure, obesity, and unhealthy cholesterol). Some researchers suggest the calcium in dairy products may be partially responsible for these benefits. However, because many dairy products are high in saturated fats and calories, doctors recommend that patients choose low-fat and nonfat dairy items. Other studies have indicated that increasing the amount of low-fat diary products in a daily diet may help reduce type 2 diabetes risk, particularly for women.

Some fat is essential for normal body function. Fats can have good or bad effects on health, depending on their chemistry. New research suggests that the type of fat is more important than the total amount of fat when it comes to reducing heart disease.

Current dietary guidelines for diabetes and heart health recommend that total fat be 25 - 35% of total daily calories. Monounsaturated fats (olive oil, canola oil, peanut oil, nuts, avocados) and omega-3 polyunsaturated fats (fish, flaxseed, walnuts) should be the first choice for fats. Omega-6 polyunsaturated fats (corn oil, safflower, oil, sunflower oil, soybean oil) are the second choice. Limit saturated fat to less than 7% of total daily calories. Limit trans-fats (margarine, commercial baked goods, snack and fried foods) to less than 1% of total calories.

All fats, good or bad, are high in calories compared to proteins and carbohydrates. In order to calculate daily fat intake, multiply the number of fat grams eaten by nine (1 fat gram is equal to 9 calories, whether it's oil or fat) and divide by the number of total daily calories desired. One teaspoon of oil, butter, or other fats equals about 5 grams of fat. All fats, no matter what the source, add the same calories. The American Heart Association recommends that fats and oils have less than 2 grams of saturated fat per tablespoon.

Try to replace saturated fats and trans fatty acids with unsaturated fats from plant and fish oils. Omega-3 fatty acids, which are found in fish and plant sources, are a good source of unsaturated fats. Generally, two servings of fish per week provide a healthful amount of omega-3 fatty acids.

The Chemistry of Fats and Cholesterol.

Fatty Acids. All fats and oils found in foods are made up of chains of molecules called fatty acids. There are three major chains: saturated fatty acid (found mostly in animal products) and two unsaturated fatty acids -- monounsaturated and polyunsaturated fatty acids (found in plant products). The oils and fats that people and animals eat are nearly always mixtures of these three chains, but one type of fatty acid usually predominates in specific oils or fats.
Essential Fatty Acids. In addition, there are three chemical subgroups of polyunsaturated fatty acids called essential fatty acids: omega-3 and omega-6 polyunsaturated fatty acids, and omega-9 monounsaturated fatty acids.
Trans Fatty Acids. To complicate matters, there are also trans-fatty acids, which are not natural but are manufactured by adding hydrogen atoms to polyunsaturated fatty acids (called hydrogenation).

Harmful Fats. Reducing consumption of saturated fats and trans-fatty acids is the first essential step in managing cholesterol levels through diet.

Saturated Fats. Saturated fats are found predominantly in animal products, including meat and dairy products. They are strongly associated with higher cholesterol levels, and they may be even more dangerous in women than in men. High-fat meals are associated with sudden surges in triglyceride levels and other lipids along with impaired blood flow in the arteries to the heart. (Tropical oils such as palm, coconut, and cocoa butter are also high in saturated fats.)
Trans Fatty Acids. Trans fatty acids are manufactured fats created during a process called hydrogenation, which is aimed at stabilizing polyunsaturated oils to prevent them from becoming rancid and to keep them solid at room temperature. They are particularly dangerous for the heart and may pose a risk for certain cancers. These partially hydrogenated fats are even worse than saturated fats. Studies report that high consumption of these fats reduces HDL and raises LDL cholesterol levels, has harmful effects on the linings of the arteries, and may increase the risk for type 2 diabetes. Hydrogenated fats are used in stick margarine and in many fast foods and baked goods, including most commercially produced white breads. (Liquid margarine is not hydrogenated and is recommended.) The FDA ordered that food labels list the amount of trans fatty acids in food products beginning in January 2006.

Beneficial Fats and Oils. Some fat is essential for health, and fat is essential for healthy development in children. Public attention has mainly focused on the possible benefits or hazards of monounsaturated (MUFA) and polyunsaturated (PUFA) fats.

Polyunsaturated fats are found in safflower, sunflower, corn, and cottonseed oils and fish.
Monounsaturated fats are mostly present in olive, canola, and peanut oils and in most nuts. (Canola is the least saturated of all the fats.) Studies report that replacing carbohydrates with monounsaturated fats improves glucose control after meals and reduces triglycerides in people with type 2 diabetes. Oils are more calorie-dense, however, and such patients should be wary of weight gain.

Researchers are most interested in the smaller fatty-acid building blocks contained in both oils, which may have more specific effects on lipids. Three important fatty acids are the essential fatty acids omega-3, omega-6, and omega-9.

Omega-3 fatty acids are found in fish oil (docosahexaenoic and eicosapentaneoic acids) and plants (alpha-linolenic acid).

Docosahexaenoic (DHA) and Eicosapentaneoic (EPA) Acids. DHA and EPA are found in fish oils, and evidence suggests that they have significant benefits for the heart, including reducing sudden death from heart disease, inflammation, blood clotting factors, blood pressure, and improving triglyceride and HDL levels. Results from a study presented at the 2005 meeting of the American Heart Association suggested that daily EPA supplements plus statin therapy can protect against heart attack, angina, and coronary artery disease. However, although fish and fish oil are good for the heart, patients who have an implantable defibrillator should not take fish oil supplements.

Alpha-linolenic Acid. Alpha-linolenic acid is a plant precursor of DHA, which means the body can convert it to DHA. Sources include canola oil, soybeans, flaxseed, and certain nuts and seeds (walnut, flax, chia and sometimes pumpkin seed). Some, but not all, studies suggest that oils or foods containing these oils may also be heart-protective. Supplements or foods containing these oils may also protest the heart. For example studies have reported heart protection from flaxseed supplements and also from nuts, such as almonds, macadamia, and walnuts. Nuts are high in calories, however.

Omega-6 polyunsaturated fatty acids are found in corn, safflower, soybean, and sunflower oil. PUFA oils containing omega-6 fatty acids constitute most of the oils consumed in the US. Some omega-6 fatty acids are important for health. However, high intake of these fats may be associated with weight gain in the abdomen (the so-called apple shape), a risk factor for heart disease. High consumption is also associated with a higher risk for certain cancer and some chronic diseases.

Omega-9 monounsaturated fatty acids are contained in canola and olive oil, which help protect the heart.

Research suggests that a healthy balance of all these fats may be important and that our current Western diet contains an unhealthy ratio of omega-6 to omega-3 fatty acids (10 to 1). Omega-9 fatty acids may also contain chemicals that block harmful factors found in omega-6 fatty acids. Researchers suggest that the most benefits may be found in mixture of all three fatty acids found in both poly- and monounsaturated oils, but in modest amounts that do not add too many calories.

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. [See Box Fat Substitutes and Artificial Sweeteners.]

The story on cholesterol found in the diet is not entirely straightforward. The body produces cholesterol naturally or obtains it through meals. Animal-based food products contain cholesterol. High amounts occur in meat, dairy products, egg yolks, and shellfish. (Plant foods, such as fruits, nuts, grains, do not contain cholesterol.) The American Heart Association recommends no more than 300 mg of dietary cholesterol per day for the general population and no more than 200 mg daily for those with high cholesterol.

Antioxidant Vitamins. Vitamins C and E are most studied for their health effects because they serve as antioxidants. Antioxidants are chemicals that act as scavengers of particles known as oxygen-free radicals (also sometimes called oxidants). High intake of foods rich in these vitamins (as well as other food chemicals) have been associated with many health benefits, including prevention of heart problems.

Research on the effects of vitamin supplements on heart disease and diabetes, however, has been mixed. Although some research initially observed favorable effects from vitamin E in preventing blood clots and build-up of plaque on blood vessel walls, most studies found no heart protection from either vitamin E or C supplements. A 2005 Journal of the American Medical Association study found that vitamin E supplements can actually increase the risk of heart failure, especially for patients with diabetes or vascular diseases. In addition, vitamin E had no effect on preventing cancer or heart disease.

Because of the lack of scientific evidence for benefit, the American Diabetes Association does not recommend regular use of vitamin supplements, except for people who have vitamin deficiencies. Researchers, however, are still studying the treatment possibilities of antioxidants. A 2006 study suggested that alpha-lipoic acid, another type of antioxidant, may have promise as a treatment for diabetic peripheral neuropathy, the nerve damage condition that is a common complication of diabetes.

B Vitamins and Folic Acid. Deficiencies in the B vitamins folate (known also as folic acid), B6, and B12 have been associated with a higher risk for heart disease in some studies. Such deficiencies produce higher blood levels of homocysteine, an amino acid that has been associated with a higher risk for heart disease, stroke, and heart failure.

Researchers have been studying whether vitamin B supplements can reduce homocysteine levels and, consequently, heart disease risks. Several major 2006 studies indicated that while B vitamin supplements help lower homocysteine levels, they have no effect on heart disease. The studies, published in the New England Journal of Medicine, examined patients who had either recently had a heart attack or who suffered from diabetes or heart disease. Results showed a similar number of heart attacks and strokes among patients who took folic acid, B6, and B12 vitamins and those who received placebo. Some experts think that homocysteine may be a marker for heart disease rather than a cause of it.

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 doctor should prescribe niacin in order to ensure its safety and effectiveness.

Patients with type 2 diabetes who take metformin (Glucophage) should be aware that this drug can interfere with vitamin B12 absorption. Calcium supplements may help counteract metformin-associated vitamin B12 deficiency.

Most experts recommend salt restriction in people who have high blood pressure. Some people, however, are much more sensitive to harmful effects from salt than others:

People at Risk for Salt-Sensitivity. About half of people with hypertension have blood pressure that reacts significantly to salt. Such people are known as salt-sensitive. Among those at highest risk for salt sensitivity are African Americans, people with diabetes, and elderly people.
Overweight People. Overweight individuals may absorb and retain sodium differently from people with normal weights. One study reported that high sodium intake was associated with an increased risk of heart disease and all-cause mortality in overweight, but not in normal weight, people. Reducing sodium can also help reduce the risk of stroke in people who are overweight.

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. 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.

Calcium. Calcium supplements may be important in older patients with diabetes to help reduce the risk for osteoporosis, particularly if their diets are low in dairy products.

Potassium. 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. In fact, there is some evidence that a potassium-rich diet can reduce the risk of stroke by 22 - 40%. Current 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 from the fruits and vegetables that contain them. Potassium-rich foods include bananas, oranges, pears, prunes, cantaloupes, tomatoes, dried peas and beans, nuts, potatoes, and avocados.

However, patients with diabetic nephropathy (kidney disease) and kidney failure need to restrict dietary potassium, as well as phosphorus. Kidney problems can cause potassium overload and medications commonly used in diabetes, (such as ACE inhibitors or potassium-sparing diuretics), also limit the kidney's ability to excrete potassium. No one should take potassium supplements without consulting a doctor. The best source of potassium is from the fruits and vegetables that contain them.

Magnesium. Magnesium deficiency may have some role in insulin resistance and high blood pressure. Research indicates that magnesium-rich diets may help lower type 2 diabetes risk. Whole grain breads and cereals, nuts (almonds, cashews, soybeans), and certain fruits and vegetables (spinach, avocados, beans) are excellent dietary sources of magnesium. Dietary supplements do not provide any benefit. Persons who live in soft water areas, who use diuretics, or who have other risk factors for magnesium deficiency may require more dietary magnesium than others.

Chromium. Some studies have reported an association between deficiencies in the mineral chromium and a higher risk for type 2 diabetes. Studies on fat rats that were given chromium reported improvement in insulin sensitivity and glucose metabolism. Most studies on type 2 patients, however, reported little or no effect on glucose metabolism and some even reported adverse side effects.

Selenium. Selenium, a trace mineral, does not reduce diabetes risk. In fact, it may increase it. In a 2007 study, researchers found that people who took selenium supplements had more than 1.5 times the risk of developing type 2 diabetes as those who did not take the supplements. The higher the blood level of selenium, the greater the risk. An average healthy diet supplies adequate amounts of selenium and there is no need to take dietary supplements.

Zinc. Many patients with type 2 diabetes are also deficient in zinc; more studies are needed to establish the benefits or risks of taking supplements. Zinc has some toxic side effects, and some studies have associated high zinc intake with prostate cancer.

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 a number of reported cases of serious and even lethal side effects from herbal products. Patients should always check with their doctors before using any herbal remedies or dietary supplements.

Traditional herbal remedies for diabetes include bitter melon, fenugreek, and Gymnema sylvestre. These herbs may have properties that help lower blood sugar. However, there have been few well-designed studies and there is not enough evidence to recommend them for prevention or treatment of diabetes.

Several recent preliminary studies suggest that cinnamon may help improve blood sugar and lipid levels. One small study found beneficial effects for people with type 2 diabetes who took between 1 - 6 grams (equivalent to 0.25 - 1.25 teaspoons) of cinnamon each day.

Various fraudulent products are often sold on the Internet as “cures” or treatments for diabetes. These dietary supplements have not been studied or approved. In 2006, the FDA and Federal Trade Commission (FTC) launched a crackdown on these scams. The FDA and FTC warn patients with diabetes not to be duped by bogus and unproven remedies.

Water. Many heart risk factors, especially those associated with blood clotting, are elevated with dehydration. In one study, drinking five or more glasses of water a day was significantly associated with a lower risk for fatal heart events than drinking two or fewer glasses a day.

Alcohol. A number of studies have found that light to moderate intake of alcohol may provide protection from heart disease and type 2 diabetes. Some research suggests that alcohol has anti-inflammatory properties that protect arteries from injury. Red wine in particular may have specific benefits for people with type 2 diabetes. It has strong antioxidant effects that benefit the heart. Some evidence also suggests that red wine may improve insulin sensitivity and reduce blood glucose levels and may even protect against type 2 diabetes. The American Diabetes Association recommends limiting alcoholic beverages to 1 drink per day for non-pregnant adult women and 2 drinks per day for adult men.

Tea. Although it contains caffeine, tea, both black and green, is often cited for its health benefits. Green tea is especially is rich in chemicals that offer protection against damaging forms of LDL. In one study, for example, higher intake, particularly by women, was associated with a lower risk for severe coronary artery disease. Black tea has also been associated with heart health. In one study oolong tea, a partially fermented tea, was specifically associated with lower blood sugar levels in patients with type 2 diabetes.

Coffee. Many studies have noted an association between coffee consumption and reduced risk for developing type 2 diabetes. A 2006 study of 29,000 postmenopausal women confirmed this reduced risk. Compared to non-coffee drinkers, women who drank at least 6 cups a day of coffee (either regular or decaf) were 22% less likely to develop type 2 diabetes. Decaffeinated coffee was even more beneficial -- women who drank at least 6 cups a day of decaf were 33% less likely to develop diabetes than women who did not drink coffee. Researchers are still not certain how coffee protects against diabetes. Neither the caffeine in coffee nor the mineral magnesium have a preventive effect. It may be that coffee contains antioxidant properties that protect the pancreas’ insulin-producing cells.

Weight Control for Type 2 Diabetes

The American Diabetes Association recommends that patients aim for a small but consistent weight loss of ½ - 1 pound per week. Most patients should follow a diet that supplies at least 1,000 - 1,200 kcal/day for women and 1,200 - 1,600 kcal/day for men.

Even modest weight loss can reduce the risk factors for heart disease and diabetes. There are many approaches to dieting and many claims for great success with various fad diets. They include calorie restriction, low-fat/high-fiber, or high protein and fat/low carbohydrates. Some evidence suggests that people may respond differently to specific diets depending on whether their weight is overly distributed around the abdomen.

Lifelong changes in eating habits, physical activity, and attitudes about food and weight are essential to weight management. Unfortunately, although many people can lose weight initially, it is very difficult to maintain weight loss. People with type 2 diabetes may have a particularly difficult time. Here are some general suggestions that may be helpful:

Start with realistic goals. When overweight people achieve even modest weight loss they reduce risk factors in the heart. Ideally, overweight patients should strive for 7% weight loss or better, particularly people with type 2 diabetes.
A regular exercise program is essential for maintaining weight loss. If there are no health prohibitions, choose one that is enjoyable. Check with a doctor about any health consideration. [See In-Depth Report #29: Exercise.]
Hunger pangs should not be taken 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 track calories carefully. Studies on weight control that depend on self-reporting of food intake frequently reveal that subjects badly misjudge how much they eat (typically underestimating high-calorie foods and overestimating low-calorie foods). In one study, even dietitians underreported their calorie intake by 10%. People who do not carefully note everything they eat tend to take in excessive calories when they believe they are dieting.
For patients who cannot lose weight with diet alone, effective weight-loss medications are now available, including orlistat (Xenical) and sibutramine (Meridia). Orlistat may have particular benefits for patients with type 2 diabetes. This drug may delay or even prevent the onset or progression of diabetes. It may also improve cholesterol levels, regardless of weight loss. A non-prescription form of orlistat, Alli, is now available. Sibutramine is also helpful in weight loss but should not be used by patients with high blood pressure or kidney or liver problems.
Once a person has lost weight, maintenance is required. To maintain a healthy weight, make careful decisions about how many calories you consume in food and how many calories you expend through physical activity. Such thinking will eventually become automatic.
A procedure known as bariatric surgery has been very helpful in producing rapid weight loss and improving insulin and glucose levels in people with diabetes.

Even repeated weight loss failure is no reason to give up. [See In-Depth Report #53: Weight control and diet.]

Calorie restriction has been the cornerstone of obesity treatment. Restricting calories in such cases also appears to have beneficial effects on cholesterol levels, including reducing LDL and triglycerides and increasing HDL levels.

The standard dietary recommendations for losing weight are:

As a rough rule of thumb, 1 pound of fat equals about 3,500 calories, so one 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 the daily calorie requirements for specific individuals, 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 moderately active woman who wants to maintain a weight of 135 pounds and is mildly active might need only 12 calories per pound (1,620 calories a day). A 25-year old female athlete who wants to maintain the same weight might need 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). Avoid saturated fats (found in animal products).

Heart-Healthy Diets

In 2006, the American Heart Association (AHA) issued revised diet and lifestyle recommendations. The current guidelines recommend:

Balance calorie intake and physical activity to achieve or maintain a healthy body weight. (Controlling weight, quitting smoking, and exercising regularly are essential companions of any diet program. Try to get at least 30 minutes, and preferably 60 - 90 minutes, of daily exercise.)
Consume a diet rich in a variety of vegetables and fruits. Vegetables and fruits that are deeply colored (spinach, carrots, peaches, berries) are especially recommended as they have the highest micronutrient content.
Choose whole-grain, high-fiber foods. These include fruits, vegetables, and legumes (beans). Good whole grain choices include whole wheat, oats/oatmeal, rye, barley, brown rice, buckwheat, bulgur, millet, and quinoa.
Consume fish, especially oily fish, at least twice a week (about 8 ounces/week). Oily fish -- such as salmon, mackerel, and sardines -- are rich in the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Consumption of these fatty acids is linked to reduced risk of sudden death and death from coronary artery disease.
Limit daily intake of saturated fat (found mostly in animal products) to less than 7% of total calories, trans fat (found in hydrogenated fats, commercially baked products, and many fast foods) to less than 1% of total calories, and cholesterol (found in eggs, dairy products, meat, poultry, fish, shellfish) to less than 300 mg per day. Choose lean meats and vegetable alternatives (such as soy). Select fat-free and low-fat dairy products. Grill, bake, or broil fish, meat, and skinless poultry.
Use little or no salt in your foods. Reducing salt can lower blood pressure and decrease the risk of heart disease and heart failure.
Limit beverages and foods that contain added sugars (corn syrups, sucrose, glucose, fructose, maltrose, dextrose, concentrated fruit juice, honey).
If you consume alcohol, do so in moderation. The AHA recommends limiting alcohol to no more than 2 drinks per day for men and 1 drink per day for women.

[See In-Depth Report #43: Heart-healthy diet.]

Dietary guidelines from the National Cholesterol Education Program recommend:

Choose five or more servings of fresh fruits and vegetables and six or more servings of whole grains and legumes. Soluble fiber is preferred (from cereal grains, beans, peas, legumes, and many fruits and vegetables).
Fats can be up to 35% of daily calories, but no more than 7% should be from saturated fat. (People with high triglycerides or low HDL or both may need a higher fat intake.) Choose fats containing unsaturated fatty acids (from vegetables, fish, legumes, and nuts). Choose margarines containing sterols or stanols (such as Benecol or Take Control). Avoid trans fatty acids found in commercial products.
Protein choices should be fat-free and low-fat milk products, fish, legumes, skinless poultry, and lean meats.
Limit cholesterol intake to less than 200 mg per day.
Maintain healthy body weight and a healthy level of physical fitness.

The Mediterranean diet is rich in heart-healthy fiber and nutrients, including omega-3 fatty acids and antioxidants. The diet consists of fruits, vegetables, and unsaturated "good" fats, particularly olive oil. Olive oil has been associated with lower blood pressure, a lower risk for heart disease, and other benefits for people with type 2 diabetes.

There are several variations to the Mediterranean diet, but general recommendations include:

Limit red meats.
Drink one or two glasses of wine each day if alcohol is enjoyable and there are no reasons to restrict its use.
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.
Eat plenty of fresh fruits and vegetables, nuts, legumes, beans, and whole grains.
Season foods with garlic, onions, and herbs.
Use virgin olive oil.

Low-carb diets, such as South Beach, The Zone, and Sugar Busters, rely on a concept called the "glycemic index (GI)," which ranks foods by how fast and how high they cause blood sugar levels to rise. Foods on the lowest end of the index take longer to digest. Slow digestion wards off hunger pains. It also helps stabilize insulin levels. Foods high on the glycemic index include white bread, white potatoes, and pasta while low-glycemic foods include whole grains, fruit, lentils, and soybeans.

A 2006 study indicated that a high-protein, low-glycemic index diet can help produce better reductions in total and LDL cholesterol than a high-protein, high-glycemic index diet. Reducing glycemic load may also help to promote weight loss, especially for women. However, another 2006 study suggested that low-glycemic index diets that are high in carbohydrates can also promote weight loss and reduce body fat.

A 2006 review of low-carbohydrate diets found that they did help weight loss in the short term. However, while these diets appeared to lower triglyceride levels and raise HDL (“good”) cholesterol levels, they also raised overall and LDL (“bad”) cholesterol levels. A 2007 Journal of the American Medical Association study that compared four different diet plans (Atkins, Zone, Ornish, and LEARN) found that the Atkins diet helped raise HDL levels, and reduce triglyciderides, but had no effect on LDL levels nor insulin or glucose measurements. Women who followed the Atkins diet also had improved blood pressure compared to patients on the other diets. The Atkins diet resulted in slightly better weight loss (an average of 10 pounds over the course of a year versus 4 - 6 pounds for the other diet plans), which in itself may have accounted for the improved heart risk factors. Some experts think that the main finding from this study is that even a moderate weight loss can help improve heart health.

Although low-carbohydrate diets may produce good short-term weight loss, they do not appear to help patients maintain weight loss in the long term. The American Diabetes Association does not recommend low-carb diets (less than 130 g of carbohydrates per day) for treatment of overweight and obesity.

Dietary guidelines recommend keeping total fat intake to 25 - 35% of total daily calories, with saturated fat less than 7% of calories. Low-fat diets generally restrict fat intake to 20% or less of total daily calories. The Ornish program, which is recommended for some heart disease patients, limits fats even more drastically. It aims at reducing saturated fats as much as possible, restricting total fat to 10%, and increasing carbohydrates to 75% of calories.

In 2006, the largest study to date on low-fat diets found that they did not help prevent heart disease or cancer. Women in the study reduced their fat consumption to 24 - 29% of total daily calories. Some critics say that the study did not do enough to distinguish between good types of fats (monounsaturated and omega-3 polyunsaturated) and bad fats (saturated and trans fats).

Another 2006 study indicated that low-fat, vegan diets may help improve glycemic control and increase insulin sensitivity. The higher fiber content of these diets, plus lower intake of total and saturated fat, may account for some of these benefits. A vegan diet eliminates all meat and dairy products.

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.

The DASH diet recommends:

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, which may help 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 lower blood pressure even more, 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 or monounsaturated fats may help reduce heart disease risk factors. [See In-Depth Report #14: High blood pressure.]

Diabetic Exchange Lists

The objective of using diabetic exchange lists is to maintain the proper balance of carbohydrates, proteins, and fats throughout the day. Patients should meet with a dietician or diabetes nutrition expert for help in learning this approach.

In developing a menu, patients must first establish their individual dietary requirements, particularly the optimal number of daily calories and the proportion of carbohydrates, fats, and protein. The exchange lists should then be used to set up menus for each day that fulfill these requirements.

The following are some general rules:

The diabetic exchanges are six different lists of foods grouped according to similar calorie, carbohydrate, protein, and fat content; these are starch/bread, meat, vegetables, fruit, milk, and fat. A person is allowed a certain number of exchange choices from each food list per day.
The amount and type of these exchanges are based on a number of factors, including the daily exercise program, timing of insulin injections, and whether or not an individual needs to lose weight or reduce cholesterol or blood pressure levels.
Foods can be substituted for each other within an exchange list but not between lists even if they have the same calorie count.
In all lists (except in the fruit list) choices can be doubled or tripled to supply a serving of certain foods. (For example 3 starch choices equal 1.5 cups of hot cereal or 3 meat choices equal a 3-ounce hamburger.)
On the exchange lists, some foods are "free." These contain less than 20 calories per serving and can be eaten in any amount spread throughout the day unless a serving size is specified.

The following are the categories on exchange lists:

Starches and Bread. Each exchange under starches and bread contains about 15 grams of carbohydrates, 3 grams of protein, and a trace of fat for a total of 80 calories. A general rule is that a half-cup of cooked cereal, grain, or pasta equals one exchange. One ounce of a bread product is 1 serving.

Meat and Cheese. The exchange groups for meat and cheese are categorized by lean meat and low-fat substitutes, medium-fat meat and substitutes, and high-fat meat and substitutes. Use high-fat exchanges a maximum of 3 times a week. Fat should be removed before cooking. Exchange sizes on the meat list are generally 1 ounce and based on cooked meats (3 ounces of cooked meat equals 4 ounces of raw meat).

Vegetables. Exchanges for vegetables are 1/2 cup cooked, 1 cup raw, and 1/2 cup juice. Each group contains 5 grams of carbohydrates, 2 grams of protein, and 2 - 3 grams of fiber. Vegetables can be fresh or frozen; canned vegetables are less desirable because they are often high in sodium. They should be steamed or cooked in a microwave without added fat.

Fruits and Sugar. Sugars are included within the total carbohydrate count in the exchange lists. Sugars should not be more than 10% of daily carbohydrates. Each exchange contains about 15 grams of carbohydrates for a total of 60 calories.

Milk and Substitutes. The milk and substitutes list is categorized by fat content similar to the meat list. A milk exchange is usually 1 cup or 8 ounces. Those who are on weight-loss or low-cholesterol diets shoudl follow the skim and very low-fat milk lists -- while avoiding the whole milk group. Others should use the whole milk list very sparingly. All people with diabetes should avoid artificially sweetened milks.

Fats. A fat exchange is usually 1 teaspoon, but it may vary. People, of course, should avoid saturated and trans fatty acids and choose polyunsaturated or monounsaturated fats instead.


Calories	1,200	1,500	1,800	2,000	2,200
Starch/Bread	5	8	10	11	13
Meat	4	5	7	8	8
Vegetable	2	3	3	4	4
Fruit	3	3	3	3	3
Milk	2	2	2	2	2
Fat	3	3	3	4	5

Exercise

Sedentary habits, especially watching TV, are associated with significantly higher risks for obesity and type 2 diabetes. Regular exercise, even of moderate intensity (such as brisk walking), improves insulin sensitivity and may play a significant role in preventing type 2 diabetes -- regardless of weight loss. An important study reported a 58% lower risk for type 2 diabetes in adults who performed moderate exercise for as little as 2.5 hours a week.

Aerobic Exercises. Aerobic exercise has significant and particular benefits for people with diabetes. Regular aerobic exercise, even of moderate intensity, improves insulin sensitivity. People with diabetes are at particular risk for heart disease, so the heart-protective effects of aerobic exercise are especially important. Moderate exercise protects the heart in people with type 2 diabetes, even if they have no risk factors for heart disease other than diabetes itself. (In general, patients with diabetes should aim for a heart rate target of 55 - 85% of their maximum heart rate when exercising.)

Strength Training. Strength training, which increases muscle and reduces fat, may also be helpful for people with diabetes.

Some Precautions for People with Diabetes Who Exercise. The following are precautions for all people with diabetes, both type 1 and type 2:

Because people with diabetes are at higher than average risk for heart disease, they should always check with their doctors before undertaking vigorous exercise. For fastest results, frequent high-intensity (not high-impact) exercises are best for people who are cleared by their doctors. For people who have been sedentary or have other medical problems, lower-intensity exercises are recommended.
Strenuous strength training or high-impact exercise is not recommended for people with uncontrolled diabetes. Such exercises can strain weakened blood vessels in the eyes of patients with retinopathy. High-impact exercise may also injure blood vessels in the feet.

Patients who are taking medications that lower blood glucose, particularly insulin, should take special precautions before embarking on a workout program:

Monitor glucose levels before, during, and after workouts (glucose levels swing dramatically during exercise).
Avoid exercise if glucose levels are above 300 mg/dl or under 100 mg/dl.
Inject insulin in sites away from the muscles used during exercise; this can help avoid hypoglycemia.
Drink plenty of fluids before and during exercise; avoid alcohol, which increases the risk of hypoglycemia.
Insulin-dependent athletes may need to decrease insulin doses or take in more carbohydrates prior to exercise, but may need to take an extra dose of insulin after exercise (stress hormones released during exercise may increase blood glucose levels).
Wear good, protective footwear to help avoid injuries and wounds to the feet.

Some blood pressure drugs can interfere with exercise capacity. Patients who use blood pressure medication should consult their doctors on how to balance medications and exercise. Patients with high blood pressure should also aim to breathe as normally as possible during exercise. Holding the breath can increase blood pressure. [See In-Depth Report #29: Exercise.]

Chronic stress has been associated with the development of insulin resistance, a primary factor in diabetes. Stress can also worsen existing diabetes by impairing the patient's ability to manage the disease effectively. Stress-relieving techniques include meditation, biofeedback, relaxation response, and yoga. One study reported that yoga helped patients with type 2 diabetes reduce their need for oral medications. 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. [See In-Depth Report #31: Stress.]

Resources

www.diabetes.org -- American Diabetes Association
www.niddk.nih.gov -- National Institute of Diabetes and Digestive and Kidney Diseases
www.jdrf.org -- Juvenile Diabetes Research Foundation
www.kidney.org -- National Kidney Foundation
www.joslin.org -- Joslin Diabetes Center
www.eatright.org -- American Dietetic Association
www.nal.usda.gov/fnic -- Food and Nutrition Information Center
www.gourmetconnection.com/diabetic -- Diabetic Gourmet Magazine

References

American Diabetes Association. Nutrition recommendations and interventions for diabetes: A position statement of the American Diabetes Association. Diabetes Care. 2007 Jan;30 Suppl 1:S48-65.

American Heart Association Nutrition Committee; Lichtenstein AH, Appel LJ, Brands M, Carnethon M, Daniels S, et al. Diet and lifestyle recommendations revision 2006: a scientific statement from the American Heart Association Nutrition Committee. Circulation. 2006 Jul 4;114(1):82-96. Epub 2006 Jun 19.

Barnard ND, Cohen J, Jenkins DJ, Turner-McGrievy G, Gloede L, Jaster B, et al. A low-fat vegan diet improves glycemic control and cardiovascular risk factors in a randomized clinical trial in individuals with type 2 diabetes. Diabetes Care. 2006 Aug;29(:1777-83.

Gardner CD, Kiazand A, Alhassan S, Kim S, Stafford RS, Balise RR, et al. Comparison of the Atkins, Zone, Ornish, and LEARN diets for change in weight and related risk factors among overweight premenopausal women: the A TO Z Weight Loss Study: a randomized trial. JAMA. 2007 Mar 7;297(9):969-77.

Gillies CL, Abrams KR, Lambert PC, Cooper NJ, Sutton AJ, Hsu RT, et al. Pharmacological and lifestyle interventions to prevent or delay type 2 diabetes in people with impaired glucose tolerance: systematic review and meta-analysis. BMJ. 2007 Feb 10;334(7588):299. Epub 2007 Jan 19.

Halton TL, Willett WC, Liu S, Manson JE, Albert CM, Rexrode K, et al. Low-carbohydrate-diet score and the risk of coronary heart disease in women. N Engl J Med. 2006 Nov 9;355(19):1991-2002.

Lindstrom J, Ilanne-Parikka P, Peltonen M, Aunola S, Eriksson JG, Hemio K, et al. Sustained reduction in the incidence of type 2 diabetes by lifestyle intervention: follow-up of the Finnish Diabetes Prevention Study. Lancet. 2006 Nov 11;368(9548):1673-9.

Liu S, Choi HK, Ford E, Song Y, Klevak A, Buring JE, et al. A prospective study of dairy intake and the risk of type 2 diabetes in women. Diabetes Care. 2006 Jul;29(7):1579-84.

McMillan-Price J, Petocz P, Atkinson F, O'Neill K, Samman S, Steinbeck K, et al. Comparison of 4 diets of varying glycemic load on weight loss and cardiovascular risk reduction in overweight and obese young adults: a randomized controlled trial. Arch Intern Med. 2006 Jul 24;166(14):1466-75.

Schulze MB, Schulz M, Heidemann C, Schienkiewitz A, Hoffmann K, Boeing H. Fiber and magnesium intake and incidence of type 2 diabetes: a prospective study and meta-analysis. Arch Intern Med. 2007 May 14;167(9):956-65.

Stranges S, Marshall JR, Natarajan R, Donahue RP, Trevisan M, Combs GF, et al. Effects of long-term selenium supplementation on the incidence of type 2 diabetes: a randomized trial. Ann Intern Med. 2007 Jul 9; [Epub ahead of print]

Ting RZ, Szeto CC, Chan MH, Ma KK, Chow KM. Risk factors of vitamin B(12) deficiency in patients receiving metformin. Arch Intern Med. 2006 Oct 9;166(18):1975-9.

Ziegler D, Ametov A, Barinov A, Dyck PJ, Gurieva I, Low PA, et al. Oral treatment with alpha-lipoic acid improves symptomatic diabetic polyneuropathy: the SYDNEY 2 trial. Diabetes Care. 2006 Nov;29(11):2365-70.

Review Date:
7/20/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

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A.D.A.M. Copyright

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adam.com

Weight control and diet

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

In This Report

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

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Cancer and Weight Control:

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

Drug Warning:

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

New Over-the-Counter Medication:

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

Research News:

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

Effects of Obesity on the Body:

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

Introduction

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Biological and Medical Causes

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Click the icon to see an image of polycystic ovaries.

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

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

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

Cultural and Emotional Causes

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

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

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

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

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

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

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

Risk Factors

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Definition of Overweight in Children

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

Causes and Risk Factors for Overweight in Children

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

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

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

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

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

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

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

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

Biological Effect of Childhood Overweight on Adult Weight

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

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

Health Consequences of Childhood Overweight

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

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

Managing Overweight Children

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

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

Click the icon to see an image about TV watching.

Click the icon to see an image of childhood overweight.

Complications

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

Some studies indicate the following health risks by body mass:

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

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

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

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

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

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

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

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

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

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

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

Obesity poses many dangers to the heart and circulatory system.

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

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

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

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

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

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

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

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

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

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

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

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

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

Click the icon to see an image of prostate cancer.

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

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

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

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

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

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

Muscles and Bones

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

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

Gum disease
Cataracts
Maculopathy, an eye disease related to aging

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

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

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

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

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

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

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

Click the icon to see an image of gallstones.

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

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

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

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

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

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

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

Weight Loss and Maintenance

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

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

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


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

Weight Management

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

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

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

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

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

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

There are possible drawbacks to this approach:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Fat substitutes include the following:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Medications

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Other Treatments

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

Bariatric surgeries produce weight loss through one of two approaches:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Complications from any bariatric procedure includes the following:

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

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

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

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

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

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

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

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

Liposuction is not recommended for major weight loss.

Resources

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

References

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

A.D.A.M. Copyright

adam.com

Allergic rhinitis

FitSugar — Wed, 08 Oct 2008 17:35:27 -0700

In This Report

Highlights
Introduction
Causes
Symptoms
Risk Factors
Prognosis
Diagnosis
Treatment
Other Treatments
Decongestants
Antihistamines
Corticosteroids
Immunotherapy
Prevention
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Drug Approval

Ciclesonide (Omanaris), a corticosteroid nasal spray, has been approved for treatment of seasonal and perennial allergic rhinitis (hay fever) in adults and children age 12 years and older.

FDA Drug Warnings

The antihistamine promethazine (Phenergan) should not be given to children younger than age 2 because it may cause serious breathing problems.
Omalizumab (Xolair) may cause a life-threatening allergic reaction (anaphylaxis). This drug is used to treat allergy-related asthma, but is also being investigated as an allergy treatment.

Cough and Cold Medicines for Children

In 2007, the FDA began reviewing the safety and effectiveness of cough and cold medicines for children. These medicines contain antihistamines, decongestants, expectorants, and cough suppressants. The FDA is particularly concerned about the use of these medicines in children younger than 2 years of age. Overdoses can cause serious heart problems and death. However, many experts are concerned that the currently recommended dosages are themselves not safe.

Immunotherapy (Allergy Shots)

Immunotherapy is safe and effective for patients with allergic rhinitis, particularly those who have not been helped by other treatments, indicates a 2007 review in the Cochrane Database.
An experimental DNA-based ragweed vaccine is showing promise in early clinical trials. In a 2006 pilot study published in the New England Journal of Medicine, six weekly injections of the vaccine helped improve symptoms with benefits lasting into the following ragweed season.

Allergic Rhinitis and Sleep

Allergic rhinitis can cause sleep disorders and interfere with sleep quality, indicates a 2006 study in the Archives of Internal Medicine. In the study of nearly 600 patients with allergic rhinitis, patients with severe allergic rhinitis experienced worse sleep problems than those with mild allergic rhinitis.

Allergic Rhinitis and Parkinson’s Disease

Allergic rhinitis may be associated with the later development of the neurological disorder Parkinson’s disease, suggests a 2006 study in Neurology. Both conditions are associated with an inflammatory response.

Introduction

The nose is separated into two passages by a wall of cartilage called the septum. The nasal passages are lined with a membrane that produces a clear liquid called mucus. Mucus is a one of the body's defense systems:

The mucus traps small particles and bacteria, which may enter the nose as a person breathes.
The trapped bacteria usually do not cause harm in healthy individuals.
However, the bacteria can lead to a daily cycle of congestion and decongestion.
When one side of the nose is congested, air passes through the open (decongested) side. The sides alternate between being wide-open and partly or completely blocked.

If the congestion becomes severe or other changes occur that irritate the nasal passage, rhinitis develops. To be diagnosed with rhinitis, the patient must experience at least two of the following symptoms for an hour or more on most days:

Runny nose
Obstruction in the nasal passage
Nasal itching
Sneezing

Click the icon to see an image showing symptoms of allergic rhinitis.

These symptoms may occur as a result of colds or environmental irritants, such as allergens, cigarette smoke, chemicals, changes in temperature, stress, exercise, or other factors.

Infectious Rhinitis. If symptoms last less than 6 weeks, the condition is referred to as acute rhinitis and is usually caused by a cold or infection, or temporary overexposure to environmental chemicals or pollutants. [See In-Depth Report #94: Colds and the flu.]

Chronic Rhinitis. When rhinitis lasts for a longer period, the condition is called chronic rhinitis. Allergies are often the cause, but structural problems or chronic infections could also be to blame.

Aging Process. The elderly are at risk for chronic rhinitis as the mucous membranes become dry with age. In addition, the cartilage supporting the nasal passages weakens, causing changes in airflow. In such cases, therapy involves avoiding possible allergens and airborne irritants as well as measures to keep the nasal passages moist. Decongestants are not helpful.

Irritative Rhinitis. Irritative rhinitis is caused by an overreaction to irritants, such as cigarette smoke, dozens of other air pollutants, strong odors, alcoholic beverages, and exposure to cold. The nasal passages become red and engorged. This reaction is not the same as an allergic reaction, although both are associated with increased numbers of white blood cells called eosinophils.

Vasomotor Rhinitis. Vasomotor rhinitis, also sometimes called idiopathic or irritant rhinitis, is congestion and stuffy nose that is produced by the changes in blood vessels and nerve cells in the nasal passages. It occurs in response to irritants, including smoke, environmental toxins, changes in temperature and humidity, stress, and even sexual arousal. This over-reaction is not associated with any immune response. The biologic causes are unknown. Some research has found an association between vasomotor rhinitis and gastroesophageal reflux disorder (GERD, a common cause of heartburn), which some experts think may be due to a common defect in the nervous system that controls muscle action. Symptoms of vasomotor rhinitis are similar to most of those caused by allergies. Usually, however, they are more severe and occur predominantly on one side of the nose.

Foreign Objects. Blockage in young children is very often caused by foreign objects that they have pushed up their nose. If they are left in place, they may eventually cause infection and nasal discharge, (usually in one side of the nose), which may be yellow or green and foul smelling.

Blockage in the Nose from Polyps or Structural Abnormalities. A number of conditions may block the nasal passages. Surgery may be helpful for certain cases.

Polyps. These are soft, gray, fluid-filled sacs that develop off stalk-like structures on the mucus membrane. They impede mucus drainage and restrict airflow. Polyps usually develop from sinus infections that cause overgrowth of the mucus membrane in the nose. They do not regress on their own and may multiply and cause considerable obstruction.
Deviated Septum. A common structural abnormality that causes rhinitis is a deviated septum. The septum is the inner wall of cartilage and bone that separates the two sides of the nose. When deviated, it is not straight but shifted to one side, usually the left.
Other Causes of Blockage. Rarely, cleft palates, overgrowth of bones in the nose, or tumors cause rhinitis.

Nonallergic Rhinitis in Children. Chronic nasal congestion in children often accompanies a susceptibility to ear, sinus, or adenoid infections. Adenoids are spongy tissue masses located between ends of the nasal passages and the soft tissue in the back of the throat. Enlarged adenoids may also cause ear problems. The bacteria that cause these other infections, however, are not usually the cause of this chronic rhinitis.

Medications and Illegal Drugs. A number of drugs can cause rhinitis or worsen it in people with conditions such as deviated septum, allergies, or vasomotor rhinitis:

Overuse of decongestant sprays used to treat nasal congestion can, over time (3 - 5 days) cause inflammation in the nasal passages and worsen rhinitis.
Many people with allergies and asthma are sensitive to common painkillers known as nonsteroidal anti-inflammatory drugs (NSAIDs). These include aspirin, ibuprofen (Motrin, Advil, Nuprin, Rufen), and naproxen (Aleve), among many others. Aspirin and products containing aspirin can even cause life-threatening asthma attacks in some highly susceptible individuals. NSAIDs vary, however, and some patients may not have a reaction to all of them. For minor pain, acetaminophen (Tylenol), which is not an NSAID, is usually recommended for patients with intolerance to NSAIDs. A pharmacist should be consulted if the ingredients of any over-the-counter preparations are not known.
Other medications that may cause rhinitis include oral contraceptives, hormone replacement therapy, anti-anxiety drugs (particularly alprazolam), some antidepressants, and some blood pressure medications, including beta-blockers and vasodilators.
Sniffing cocaine damages nasal passages and can cause chronic rhinitis.

Estrogen in Women. Elevated levels of estrogen appear to increase mucus production and swelling in the nasal passages and can cause congestion. This effect is most apparent in women during pregnancy. In such cases the condition usually clears up after delivery. Oral contraceptives and hormone replacement therapies that contain estrogen have also been associated with nasal congestion in some women.

Medical Conditions. Hypothyroidism is associated with chronic rhinitis. People with certain genetic or other medical conditions that specifically affect the mucous membranes are at also risk, although rhinitis in such people is apt to be only one of many more serious conditions, including chronic sinusitis and respiratory problems. Wegener's granulomatosis, for example, is a serious but very rare illness that causes long-term swelling and tumor-like masses in air passages.

Rare genetic disorders that cause chronic rhinitis include the following:

Cystic fibrosis, in which the mucus is very thick.
Kartagener's syndrome. With this condition the body's major internal organs are located in the mirror-image position of their normal location. In addition, the body's cilia (hair-like-projections on many body tissues that help to move mucus and other fluids) are impaired or motionless.

In both disorders, mucus build-up also produces an environment favorable to infection-causing organisms.

Click the icon to see an image of a deviated septum.

Click the icon to see an image of the adenoids.

Causes

The allergic process, called atopy, and its connection to asthma is not completely understood. It involves various airborne allergens or other triggers that set off a cascade of events in the immune system leading to inflammation and hyperreactivity in the airways.

The conductor in an orchestra of immune factors that contribute to allergies and asthma appears to be a category of white blood cells known as helper T cells, in particular a subgroup called Th2 cells.
Th2 cells overproduce interleukins (ILs), immune factors that are molecular members of a family called cytokines, which are involved in the inflammatory process.

Interleukins 4, 9, and 13 may be responsible for a first-phase asthma attack. These interleukins stimulate the production and release of antibody groups known as immunoglobulin E (IgE). People with both asthma and allergies appear to have a genetic predisposition for overproducing IgE.
During an allergic attack, these IgE antibodies bind to special cells in the immune system called mast cells, which are generally concentrated in the lungs, skin, and mucous membranes. This bond triggers the release of a number of active chemicals, importantly potent molecules known as leukotrienes. These chemicals cause airway spasms, overproduce mucus, and activate nerve endings in the airway lining.
Another cytokine, interleukin 5, appears to contribute to a late-phase inflammatory response. This interleukin attracts white blood cells known as eosinophils. These cells accumulate and remain in the airways after the first attack. They persist for weeks and mediate the release of other damaging particles that remain in the airways.

One theory blames the dramatic increase in asthma and allergies on the reductions in childhood infections that have occurred with modern hygiene and antibiotic use. The basic theory rests on the idea that infections stimulate production of specific immune factors called Th1 cells. As these cells build up, they replace other immune factors called Th2 cells, which react to allergens -- a less serious threat to the body. Without infections to stimulate the production of the Th1 infection fighters, the Th2 allergen fighters are not replaced, and they persist at high levels, making the growing child more susceptible to allergies and asthma.

A number of different studies support this theory:

Some studies suggest that being part of a large family or attending day care increases the risk for early respiratory infections but reduces the risk of childhood asthma. The occasional cold, then, may be protective.
In a 2002 study, researchers measured levels of bacterial byproducts called endotoxins in the mattress dust of 812 children. Those with the highest levels had an 80% lower rate in allergies and asthma.
Another study further found a strong association between allergy development and the absence of certain beneficial bacteria (called probiotics) in infants' intestines. Infants who were born in more hygienic environments tended to lack these bacteria. Antibiotic overuse and modern hygiene may reduce these helpful organisms. (Probiotics are available in active yogurt cultures and in supplements, which are being studied for protection.)

According to many studies, the standard vaccinations against serious childhood infections pose no risk for developing asthma or hay fever. Some studies have even reported lower risk for asthma and allergies in the second and third years after vaccinations.

Some evidence suggests that the increase in allergies and asthma may be due to overexposure to indoor allergens. These may include wall-to-wall carpeting, cats, and mold produced by dampness in homes. Children who spend hours indoor each day may become overexposed to indoor allergens. This exposure is intensified by the recent trend of making homes more energy-efficient, which may result in more dust mites being trapped inside. However, other studies suggest that early exposure to allergens may actually prevent the development of allergies in children.

Seasonal allergic rhinitis occurs only during periods of intense airborne pollen or spores. It is commonly, although inaccurately, called hay fever or rose fever, depending on whether it occurs in the late summer or spring. No fever accompanies this condition, and the allergic response is not dependent on either hay or roses. In general, triggers of seasonal allergy in the U.S. include:

Ragweed. Ragweed is the most dominant cause of allergic rhinitis in the U.S., affecting about 75% of allergy sufferers. One plant can release 1 million pollen grains a day. Ragweed occurs everywhere in the U.S., although it is less common in western coastal states, southern Florida, northern Maine, Alaska, and Hawaii. The effects of ragweed in the northern states are first felt in middle to late August and last until the first frost. Ragweed allergies tend to be most severe before midday.
Grasses. Grasses affect people in mid-May to late June. Grass allergies are experienced more in the late afternoon.
Tree Pollen. Small pollen grains from certain trees usually produce symptoms in late March and early April.
Mold Spores. Mold spores that grow on dead leaves and release spores into the air are common allergens throughout the spring, summer and fall. Mold spores may peak on dry windy afternoons or on damp or rainy days in the early morning.

Click the icon to see an animation about allergies.

Major weather changes, such as El Nino, can affect the timing of allergy seasons. For example, in 1998, when the effects of El Nino were very strong, allergy attacks were markedly increased, and maximum tree pollen counts occurred 2 - 4 weeks earlier and mold counts 2 - 3 months earlier than the previous year.

Allergens in the House. Allergens in the house can trigger attacks in people with year-long allergic rhinitis, called perennial rhinitis. Household allergens may include the following:

House dust and mites. Dust mites, specifically mite feces, are coated with enzymes that contain a powerful allergen.
Cockroaches
Pet dander
Molds growing on wallpaper, house plants, carpeting, and upholstery

However, some studies are suggest that early exposure to some of these allergens, including dust mites and pets, may prevent allergies from developing in the first place in children.

Fossil Fuels. There may be an association between traffic-related air pollution and allergic rhinitis. Some experts believe that refined fossil fuels, such as diesel fuel and particularly kerosene, are important triggers for allergic rhinitis. In people who already have allergies or asthma, exposure to such fossil fuels may worsen symptoms.

Symptoms

The general symptoms of rhinitis are congestion, runny nose, and postnasal drip, in which mucous drips into the throat from the back of the nasal passage, especially when lying on the back. Symptoms may vary depending on the cause of rhinitis. Symptoms of influenza and sinusitis must also be differentiated from allergies and colds.

Symptoms of allergic rhinitis occur in two phases, early and late.

Early Phase Symptoms. The early phase occurs within minutes of exposure to the allergens and includes:

Runny nose
Frequent or repetitive sneezing
Itching in the nose, eyes, throat, or roof of the mouth

Late-Phase Symptoms. The late phase occurs 4 - 8 hours later and may include one or more of these symptoms:

Nasal congestion and possibly plugged ears. Children may push their nose upward with the palm of their hand or twitch their nose rabbit-like to clear the obstruction.
Fatigue.
Mental changes can include irritability, a slight decrease in attention span, worsened memory, and slower thinking.
Other common physical symptoms include a decreased sense of smell, plugged ears, sinus headache, postnasal drip or some combination. In severe allergies, dark circles may develop under the eye. The lower eyelid may be puffy and lined with creases.

Risk Factors

Allergic rhinitis affects between 20 - 40 million Americans of all ages. As with asthma and many upper respiratory infections, the incidence in allergic rhinitis is increasing. Allergies most often appear first in childhood, and allergic rhinitis is the most common chronic condition in childhood, although it can develop at any age. About 20% of allergic rhinitis cases are due to seasonal allergies, 40% to perennial (chronic) rhinitis, and the rest are mixed.

Genetic factors are the major determinants of allergies.

If both parents have an allergy, the child's risk is 75%.
If one parent is allergic, the child's risk is 50%.

Having other allergies increases the risk for allergic rhinitis. Here are some examples:

Young children who have eczema (an allergic skin reaction) have a later risk for allergic rhinitis and asthma. In fact, a family history of eczema increases the risk.
Food allergies are associated with allergic rhinitis and asthma. (Early feeding patterns, time of weaning, and introduction of solid food do not appear to affect this risk.)
Asthma, especially in patients who develop it as adults, may increase allergic sensitivity to ragweed and other allergens. Patients who have asthma and a genetic tendency towards allergies (atopy) are also at risk for rhinitis.

Birth Month. Some studies report a higher risk of allergies and asthma in children born in winter months and lower risk in those born during the summer.

Breastfeeding. Some researchers suggest that the dramatic increase in asthma and allergies may be due to fewer women breastfeeding their infants. In a number of studies, breastfeeding has been associated with a lower risk for allergies and asthma -- at least until age 2. Breastfeeding can also help prevent other upper respiratory infections. The American Academy of Pediatrics recommends feeding infants exclusively breast milk for the first 6 months of life.

Prognosis

Seasonal allergic rhinitis tends to diminish as a person ages. The earlier the symptoms start, the greater the chances for improvement. People who develop hay fever in early childhood tend not to have the allergy in adulthood. In one study, over half of allergic subjects reported that by 40 years of age their symptoms had decreased, and a quarter were symptom-free. In some cases, allergies go into remission for years and then return later in life. People who develop allergies after age 20, however, tend to continue to have hay fever at least into middle age.

People with allergic rhinitis may be at higher risk for other allergies, including potentially serious food or latex allergies.

Although allergic rhinitis is not considered a serious condition, it nonetheless can interfere with many important aspects of life. A 2006 survey of nasal allergy sufferers reported that symptoms made patients feel tired (80%), miserable (65%), irritable (62%), and interfered with work performance (52%).

People with allergic rhinitis, particularly those with perennial allergic rhinitis, may experience sleep disorders and daytime fatigue. Often they attribute this to medication, but studies suggest congestion may be the culprit in these symptoms. In addition, a 2002 study indicated that patients with seasonal allergies experience hundreds of brief, subtle awakenings, called "microarousals," each night. In such cases, people are not aware that they wake up, but such events can cause fatigue the next day. A 2006 study of nearly 600 patients with allergic rhinitis found that sleep disorders and poor sleep quality were prevalent. Patients who had severe allergic rhinitis had worse sleep problems than those with mild allergic rhinitis.

Asthma and allergies often coexist, and the allergic response plays a strong role in childhood asthma. About 70 - 85% of children with asthma have allergies. Aggressive treatment of allergies in children with asthma can lower the risk for asthma attacks. Treating allergies in children may also help prevent the onset of asthma.

Any chronic rhinitis, whether allergic or nonallergic, can cause swelling in the turbinate, which may become persistent (turbinate hypertrophy). The turbinate is a tiny shelf-like bony structure that protrudes in the nasal passageways. It helps warm, humidify, and clean the air that passes over it. If turbinate hypertrophy develops, it causes persistent nasal congestion and, sometimes, pressure and headache in the middle of the face and forehead. This condition requires surgery.

Children with severe allergies may have a higher risk for behavioral problems than those without allergies. Some research suggests that allergic rhinitis is responsible for 2 million missed school days each year.
There have been reports that 30 - 45% of people with allergic rhinitis also suffer from ear infections (otitis media).
Chronic nasal obstruction from year-round allergies can affect a child's appearance. If a child can only breathe through the mouth, the continual force of air passing through the oral cavity can change facial development. Such changes may include an elongated face and an overbite from teeth coming in at an abnormal angle.
Chronic rhinitis can cause headaches and also affect a child's sleep, concentration, hearing, appetite, and growth.

Depression. Some evidence has linked depression with allergies. A 2002 study, for example, found that people with depression reported a higher rate of allergic disorders (71%) compared to nondepressed individuals (43%). During allergy season, patients with allergies were more likely to experience mood changes, including sadness, lethargy, and mental fatigue, than at other times. Some evidence suggests that specific immune factors in the allergic response can cause depressive symptoms. Other research indicates that both may have a common cause.

Parkinson’s Disease. A 2006 study suggested that allergic rhinitis may be associated with the later development of the neurological disorder Parkinson’s disease. The researchers think that the inflammatory response may be the link between the two conditions. However, there is not yet any evidence that treating allergic rhinitis can prevent Parkinson’s disease.

Chronic Fatigue Syndrome (CFS). Some, although not all, studies have reported that a majority of patients with CFS also have allergies to foods, pollen, metals (such as nickel or mercury), or other substances. One theory is that allergens, like viral infections, may trigger a harmful overreaction of the immune system that can cause fatigue, joint aches, and fever as well as hormone and brain chemical disturbances. (However, most people with allergies do not have CFS.)

Diagnosis

To determine the cause of allergic rhinitis, the doctor will ask a number of questions about:

Time of day and year of rhinitis episodes. Rhinitis that appears seasonally is typically due to pollens and outdoor allergens. If symptoms occur throughout the year, the doctor will suspect perennial allergic or non-allergic rhinitis.
Family history of allergies.
History of medical problems.
In women, if they are pregnant or taking drugs that contain estrogen (oral contraceptives, hormone replacement therapy).
Use of other medications including decongestants, which can cause a rebound effect.
Pets.
Any additional unusual symptoms. As examples, bloody nasal discharge and obstruction in only one nasal passage could suggest a tumor. Fatigue, sensitivity to cold, weight gain, and depression may be signs of hypothyroidism.

The doctor will examine the inside of the nose with an instrument called a speculum. This is a painless examination allowing the doctor to check for redness and other signs of inflammation. The doctor will also usually check the eyes, ears, and chest.

A skin test is a simple method for detecting common allergens. Patients are usually tested for a panel of common allergens. Skin tests are rarely needed to diagnose mild seasonal allergic rhinitis, since the cause is usually obvious. The skin test is not appropriate for children younger than age 3.

The procedure is as follows:

Patients should not take antihistamines for at least 12 - 72 hours before the test. Otherwise an allergic reaction may not show up.
Small amounts of suspected allergens are applied to the skin with a needle prick or scratch or are injected a few cells deep into the skin. The injection test may be more sensitive than the standard prick test.
If an allergy is present, a hive (a swollen reddened area) forms within about 20 minutes.

The test is not completely accurate. For instance, a 2001 study reported that testing detected allergies in less than half of children with rhinitis. Furthermore, about 15 - 20% of people may have a skin reaction without actually having an allergy.

Nasal Smear. The doctor may take a nasal smear. The nasal secretion is examined microscopically for factors that might indicate a cause, such as increased numbers of white blood cells, indicating infection, or high counts of eosinophils. High eosinophil counts indicate an allergic condition, but low counts do not rule out allergic rhinitis.

Tests for IgE. Blood tests for IgE immunoglobulin production may also be performed. One test is called the radioallergosorbent Test (RAST), used to detect increased levels of allergen-specific IgE in response to particular allergens. Blood tests for IgE may be less accurate than skin tests. They should be performed only on patients who cannot undergo skin testing or when skin test results are uncertain.

In people with chronic rhinitis, the doctor may also check for sinusitis. Imaging tests may be useful if other tests are ambiguous.

A test called transillumination, in which a doctor shines a bright light against the patient's cheek or forehead, is an inexpensive method for checking for abnormalities in the sinus cavities, although it is not highly accurate.
CT scans may be useful for some cases of sinusitis.

Click the icon to see an image of a CT scan.

In certain cases of chronic or unresponsive seasonal rhinitis, a doctor may use endoscopy to examine for any irregularities in the nose structure. Endoscopy uses a tube inserted through the nose that contains a miniature camera to view the passageways.

Treatment

If rhinitis is caused by non-allergic conditions, particularly if there are accompanying symptoms indicating a serious problem, the doctor should treat any underlying disorders. If rhinitis is caused by medications, such as decongestants, the patient may need to stop taking them or find alternatives.

Patients with chronic allergic rhinitis may require daily medications. Patients with severe seasonal allergies should start medications a few weeks before the pollen season and continue taking them until the season is over. Effective medications include:

Drugs that reduce the inflammatory response are important for preventing severe allergic rhinitis. Nasal corticosteroids (commonly called steroids) are now considered to be the most effective measure for preventing allergy attacks. Other anti-inflammatory drugs include leukotriene-antagonists and nasal cromolyn.
Antihistamine tablets relieve sneezing and itching and can prevent nasal congestion before an allergy attack. Many brands are available by prescription and over-the-counter.
Immunotherapy ("allergy shots") may be considered for patients with severe seasonal allergies that do not respond to treatment. It may also prevent asthma and the development of new allergies in children. Many experts now recommend immunotherapy for people with both asthma and allergies. Newer immunotherapeutic approaches using specially designed antibodies and vaccines are also showing promise.

All drug treatments have side effects, some very unpleasant and, in rare cases, serious. Patients may need to try different drugs until they find one that relieves symptoms without producing excessively distressing side effects.

Because seasonal allergies generally last only a few weeks, most doctors do not recommend the more potent prescription treatments for children. It is important for parents to determine if the child is actually under severe distress and that the parent is not simply responding to their own anxiety when they hear the child snorting or snoring. Prescription drugs are required only in severe cases. However, in children with both asthma and allergies, treatments for allergic rhinitis may also improve asthmatic symptoms.

Treating Mild Allergy Attacks. Mild allergy attacks usually require little more than reducing exposure to allergens and using a nasal wash. Dozens of treatments are available for allergic rhinitis. Many are available over-the-counter, but some require a prescription. They include the following:

Nasal washes
Decongestants that relieve nasal congestion and itchy eyes
Decongestant/antihistamine combinations

Due to side effects, decongestants should not be used in children ages 14 years or younger. Also, overuse of nasal decongestions can actually worsen sinus congestion.

Treating Severe Allergic Rhinitis. Patients with chronic allergic rhinitis, particularly if they also have asthma, may require daily medications. These drugs include:

Antihistamines. The newer non-sedating antihistamines -- such as cetirizine (Zyrtec), loratadine (Claritin), fexofenadine (Allegra), or desloratadine (Clarinex) -- cause less drowsiness than older antihistamines, such as Benadryl. Some of the newer drugs, such as Zyrtec and Clarinex, may also relieve nasal congestion.
Anti-inflammatory drugs. Nasal corticosteroids are now considered to be the most effective measure for preventing allergy attacks. They are recommended for patients with very severe allergies that do not respond to antihistamines.
Leukotriene-antagonists and nasal cromolyn may be beneficial in specific cases of allergies
Immunotherapy ("allergy shots") works well for many patients with severe allergies. It is also proving to reduce asthma symptoms and the use of asthma medications in patients with known allergies.

Itching and redness in the eyes sometimes respond to oral antihistamines. Eye drops, however, provide faster relief, and a combination of the two may be best. The following are eye drops for itchy eyes. Others are also available. Individual responses vary, and patients need to find which specific treatment works best for them.

Antihistamine eye drops: azelastine (Optivar), olopatadine (Patanol), ketotifen (Zaditor), levocabastine (Livostin) for relief of both nasal symptoms and itchy red eyes
Decongestant eye drops: phenylephrine (Allergan Relief), naphazoline (Naphcon, Opcon-A, VasoClear), tetrahydrozoline (Murine Plus, Visine)
Combination decongestant/antihistamine: Visine A.
Corticosteroids: loteprednol (Lotemax, Alrex), pemirolast (Alamast).

General Side Effects and Warning.

All eye drops can cause stinging, and some may result in headache and congestion.
No one should continue taking eye drops if they experience pain, changes in vision, worsened redness, or irritation, or if the condition lasts more than 3 days.
Do not touch the tip of the device to the eye or touch other surfaces with it. Replace the cap after using. Discard any solution that changes color or becomes cloudy.
People who have heart disease, high blood pressure, an enlarged prostate gland, or glaucoma should talk to their doctor before taking these types of eye drops.

Other Treatments

For mild allergic rhinitis, a nasal wash can be helpful for removing mucus from the nose. You can purchase a saline solution at a drug store or make one at home (one cup of warm water, half teaspoon salt, pinch of baking soda). Over-the-counter saline nasal sprays that contain benzalkonium chloride as a preservative may actually worsen symptoms and infection.

Simple method for administering a nasal wash:

Lean over the sink head down.
Pour some solution into the palm of the hand and inhale it through the nose, one nostril at a time.
Spit the remaining solution out.
Gently blow the nose.

The solution may also be inserted into the nose using a large rubber ear syringe, available at a pharmacy. In this case the process is:

Lean over the sink head down.
Insert only the tip of the syringe into one nostril.
Gently squeeze the bulb several times to wash the nasal passage.
Then press the bulb firmly enough so that the solution passes into the mouth.
Repeat the process in the other nostril.

Nearly half of asthma or allergy sufferers resort to alternative treatments. To date, however, little evidence supports treatments such as high-dose vitamins, homeopathic remedies, and most herbal remedies. Some relaxation methods, such as massage therapy, may be beneficial in reducing stress related to allergy symptoms. According to research presented at a 2004 allergy conference, acupuncture is now the most popular alternative treatment among allergy sufferers. The following are examples of recent areas of research:

Acupuncture may provide symptom relief for persistent allergic rhinitis in children, according to results published in a 2004 pediatrics journal. The study compared the effects of active versus sham acupuncture. Larger trials are needed to confirm these results.
Butterbur (also known as Petasites hybridus, butter dock, blatterdock, bog rhubarb, and exwort) is a plant found in Europe, North American, and parts of Asia. It is a traditional herbal remedy used for seasonal allergies and asthma. In a 2002 study, it was as effective and less sedating than a commonly prescribed antihistamine for treating seasonal allergies over a 2-week period.
Probiotics are beneficial bacteria that may help protect against allergies and asthma. Probiotics are available in active yogurt cultures and in supplements, which are being studied for protection.

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 a number of 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.

The following are special concerns for people with allergic rhinitis:

Grapeseed extract is sometimes touted as a natural antihistamine. A 2002 study, however, reported no benefits from it.
A 2002 study found no benefits with homeopathy immunotherapy for asthmatic patients allergic to dust mites.
Some patients have reported worse symptoms after drinking herbal teas, which may contain leaves or pollens the patient is sensitive to. Herbal remedies themselves can trigger an allergic reaction. For example, echinacea is of special concern. This herbal remedy actually boosts the immune system. People with nasal congestion may mistakenly take it because it is often used to treat colds. In the case of allergies, however, echinacea may worsen symptoms or even trigger them in people who haven't experienced them. People with autoimmune diseases or who have plant allergies should particularly avoid it.
A Chinese herbal cold and allergy remedy sold as Aller Relief contains trace amounts of aristolochic acid, a chemical that is toxic to the kidneys and a carcinogen. Products containing aristolochic acid have been associated with several reports of kidney failure in Europe. Of specific concern are studies suggesting that up to 30% of herbal patent remedies imported from China have been laced with potent pharmaceuticals such as phenacetin and steroids. Asian herbal remedies may also contain toxic metals.
Aromatherapy is often used for relaxation. Some of the exotic plant extracts in these formulas have been associated with a wide range of skin allergies.

Decongestants

For mild allergic rhinitis, a nasal wash can be helpful for removing mucus from the nose. Decongestants may help dry nasal congestion. They work by shrinking vessels in the nose. By reducing blockage, they decrease the risk of developing sinusitis caused by viruses or bacteria. Many over-the-counter decongestants are available, either in tablet form or as nasal or inhaled decongestants that are applied directly into the airways as sprays, drops, or vapors.

Nasal-delivery decongestants are applied directly into the nasal passages with a spray, gel, drops, or vapors. Nasal decongestants come in long-acting or short-acting forms. The effects of short-acting decongestants last about 4 hours; long-acting decongestants last 6 - 12 hours. The active ingredients in nasal decongestants include oxymetazoline, xylometazoline, and phenylephrine. Nasal forms work faster than oral decongestants and may not cause as much drowsiness. However, they can cause dependency and rebound.

Dependency and Rebound. The major hazard with nasal-delivery decongestants, particularly long-acting forms, is a cycle of dependency and rebound effects. The 12-hour brands pose a particular risk for this effect.

With prolonged use (more than 3 - 5 days), nasal decongestants lose effectiveness and can cause swelling in the nasal passages.
The patient then increases the frequency of the dose. As the congestion worsens, the patient may respond with even more frequent doses.
This causes dependency and increased nasal congestion.

Tips for Use. The following precautions are important for people taking nasal decongestants:

When using a nasal spray, spray each nostril once. Wait a minute to allow absorption into the mucosal tissues, and then spray again.
Do not share droppers and inhalators with other people.
Discard sprayers, inhalators, or other decongestant delivery devices when the medication is no longer needed. Over time, these devices can become reservoirs for bacteria.
Discard the medicine if it becomes cloudy or unclear.

Oral decongestants also come in many brands, which have similar ingredients. The most common active ingredient is pseudoephedrine (Sudafed, Actifed, Drixoral), sometimes in combination with an antihistamine. [The alternative decongestant, phenylpropanolamine (PPA) was taken off the market.] A small 2006 study reported that over-the-counter pseudoephedrine works just as well as the prescription drug montelukast (Singulair) in controlling allergic rhinitis symptoms. Patients in the study received a once-daily morning dose (240 mg) of ephedrine. Researchers suggest that taking pseudoephedrine in the morning, as opposed to later in the day or before bedtime, can help patients avoid side effects such as insomnia and nervousness.

Decongestants have certain adverse effects, which are more apt to occur in oral than nasal decongestants. These side effects include:

Agitation and nervousness
Drowsiness (particularly with oral decongestants and in combination with alcohol)
Changes in heart rate and blood pressure
Avoid combinations of oral decongestants with alcohol or certain drugs, including monoamine oxidase inhibitors (MAOI) and sedatives.

Individuals at Risk for Complications from Decongestants. People who may be at higher risk for complications are those with certain medical conditions, including disorders that make blood vessels highly susceptible to contraction. Such conditions include:

Heart disease
High blood pressure
Thyroid disease
Diabetes
Prostate problems that cause urinary difficulties
Migraines
Raynaud's phenomenon
High sensitivity to cold
Emphysema or chronic bronchitis. (Individuals with these conditions should particularly avoid high-potency, short-acting nasal decongestant.)
Medications that increase serotonin levels, such as certain antidepressants, anti-migraine drugs, diet pills, St. John's wort, and methamphetamine. The combination of these medicines and decongestants can cause blood vessels in the brain to narrow suddenly, causing severe headaches and even stroke.

Anyone with these conditions should not use oral or nasal decongestants without a doctor's guidance. Other people who should not use decongestants without first consulting a doctor include:

Pregnant women
Children. The American College of Chest Physicians advises against the use of over-the-counter decongestants and other cold medications in children ages 14 years or younger. Children are at particular risk for side effects that depress the central nervous system. Such symptoms cause changes in blood pressure, drowsiness, deep sleep, and, rarely, coma. In 2007, the FDA began reviewing the safety and effectiveness of cough and cold remedies for children.

In 2000, the Food and Drug Administration (FDA) took action to ban oral decongestants containing phenylpropanolamine (PPA) from the U.S. market. This action was in response to reports of an increased risk of stroke in young women who took products containing this ingredient. All major brands that previously contained PPA have now substituted other active ingredients (usually pseudoephedrine) and are safe to use.

Anyone with old forms of decongestant should check the labels and discard them if they contain phenylpropanolamine.

Antihistamines

Histamine is one of the chemicals released when antibodies overreact to allergens. It is the cause of many symptoms of allergic rhinitis. Antihistamines can help relieve:

Itching, sneezing, and nasal discharge
Other allergy symptoms unrelated to rhinitis, including hives and some rashes
Nasal congestion, for some of the newer antihistamines, such as cetirizine (Zyrtec) and desloratadine (Clarinex)

If possible, patients should take antihistamines before an anticipated allergy attack.

Many antihistamines are available. They include short-acting and long-acting forms and are available as tablets, nasal-inhalers, eye drops, and syrups. Antihistamines are generally categorized as first- and second-generation. First-generation antihistamines may cause more side effects than newer second-generation ones.

There are some notes of caution when taking any antihistamine:

Antihistamines may thicken mucus secretions and can worsen bacterial rhinitis or sinusitis.
Antihistamines can lose their effectiveness over time, and a different one may need to be tried.

First-Generation Antihistamines Ingredients and Brand Names. The older, so-called first generation antihistamines include:

Diphenhydramine (Benadryl)
Carbinoxamine (Clistin)
Clemastine (Tavist)
Chlorpheniramine (Chlor-Trimeton). Some health professionals recommend this drug if antihistamines are required during pregnancy. It may be as effective as the second generation antihistamines and much less expensive.
Brompheniramine (Dimetane)
Promethazine (Phenergan). This antihistamine should never be used for children younger than age 2 because it may cause life-threatening breathing problems.

First-generation antihistamines contain compounds called anticholinergics, which tend to produce more side effects than second-generation antihistamines.

Side Effects

Drowsiness and impaired thinking
Dry mouth
Dizziness
Agitation
Insomnia or nightmares
Sore throat
Rapid heart beat and chest tightness (uncommon and should be reported)
Men with enlarged prostate glands may experience difficulty urinating

Drowsiness and First-Generation Antihistamines. Drowsiness is the most distressing side effect reported from first-generation antihistamines, and is potentially serious. It may pose a higher than average risk for work-related and automobile accidents than alcohol, narcotics, or prescription sedatives. However, some studies have not found any strong differences in sedation between the first- and second-generation antihistamines. Still, experts caution against the first-generation antihistamines for people most at risk from sedative effects, particularly elderly individuals. To reduce risks, take the antihistamine at home a few hours before bedtime, and do not combine it with alcohol or tranquilizers. Do not drive or operate heavy machinery.

The newer second-generation antihistamines do not contain anticholinergics, so they do not usually cause drowsiness to the extent that the first generation antihistamines do. They are sometimes referred to collectively as nonsedating antihistamines.

A major 2003 analysis reported that although Benadryl, the most common first-generation antihistamine, had a more negative effect on daily activities than the newer antihistamines, the differences were modest. Researchers in the study concluded that no clear distinction exists between the first- and second-generation antihistamines.

Brand Names. The second-generation drugs include:

Loratadine (Claritin). Claritin is available over-the-counter and is approved for children ages 2 and older. Desloratadine (Clarinex) is similar to Claritin but stronger and longer-lasting. It is available only by prescription.
Cetirizine (Zyrtec). Zyrtec is approved for both indoor and outdoor allergies. It is the only antihistamine to date approved for infants as young as 6 months. It is available over-the-counter.
Fexofenadine (Allegra) is also available over-the-counter.
Acrivastine (Semprex)
Ebastine, norastemizole, levocetirizine, and mizolastine are other second-generation antihistamines under investigation in the U.S. and Europe. Some may prove to be useful for specific populations.

For nonprescription antihistamines, some studies suggest that cetirizine (Zyrtec) is more effective than Allegra or Claritin in improving symptoms, including those in children. However, cetirizine can cause drowsiness when taken at high doses.

Zyrtec and Claritin are approved for children younger than 5 years, although most antihistamines appear to be safe in children. Zyrtec is the only antihistamine approved for both indoor and outdoor allergies and for infants as young as 6 months. Both are available in syrup form. Studies with Zyrtec have reported fewer symptoms in children allergic to dust mites, and one study reported that infants with allergies who were given Zyrtec were much less likely to develop asthma later on than untreated infants. Claritin, at this time, is generally the preferred drug for young people, however, because it has the least negative effect on concentration and learning. Women who are pregnant or nursing should avoid these medications unless recommended by a doctor.

Side Effects and Precautions

Common side effects include headache, dry mouth, and dry nose. (These are often only temporary and go away during treatment.)
Drowsiness occurs in about 10% of adults and between 2 - 4% of children.
Uncommon side effects include rapid heart beat and chest tightness. Tell your doctor if these effects occur.
Extended-release forms of Claritin and Zyrtec have other ingredients that can cause other symptoms, including nervousness, restlessness, and insomnia. Some patients taking Claritin-D 24 Hour Extended Release tablets have reported obstruction in the upper gastrointestinal tract, including difficulty swallowing.

Drug and Food Interactions. Two earlier second generation drugs, terfenadine (Seldane) and astemizole (Hismanal), in rare cases, caused dangerous heart rhythm abnormalities, particularly in high doses or in people who had liver disease. They also caused interactions with certain other medications and grapefruit juice. Both Seldane and Hismanal have been taken off the market. Allegra, Zyrtec, and Claritin do not appear to pose any of the dangers associated with Seldane.

Until more is known, however, anyone who takes a second-generation antihistamine should probably avoid or use with caution combinations with grapefruit juice or the drugs that caused problems with Seldane and Hismanal. Such medications include:

The antibiotics clarithromycin (Biaxin) and troleandomycin
Certain HIV protease inhibitors
Antidepressant serotonin-reuptake inhibitors (Prozac, Paxil, and Serzone)

Azelastine (Astelin) and levocabastine (Livostin) are available in nasal spray form. They can reduce nasal congestion as well as allergy symptoms. Both reduce symptoms, although azelastine may be more effective in some patients. Their disadvantages are a bitter taste, drowsiness, and expense. They are not as effective as steroid nasal sprays.

Many prescription and non-prescription products that combine antihistamines and decongestants are available. Combinations sold over-the-counter include Allerest, Sudafed Severe Cold Formula, Vicks DayQuil, Benadryl Allergy/Sinus, Contac Day/Night Allergy & Sinus. Prescription combinations include Claritin-D, Allegra D, and Zyrtec-D. Symptoms may improve within 60 minutes, with congestion clearing up first.

Corticosteroids

A number of drugs are available for reducing the inflammatory response in allergies. These drugs can help prevent an allergy attack from occurring.

Nasal-spray corticosteroids (commonly called steroids) are considered the most effective drugs for treating severe allergic rhinitis. Corticosteroids suppress important stress and other hormones in a region of the brain called the HPA axis. The suppression of these hormones blocks the inflammatory response that triggers an allergic attack. Steroids do not relieve symptoms immediately. It may take several hours before their effects are felt. Nasal spray steroids benefits include:

Reducing inflammation and mucus production
Improving night sleep and daytime alertness in patients with perennial allergic rhinitis
Treating polyps in the nasal passages

Comparison studies report that nasal steroid sprays work better than second generation antihistamines, such as loratadine (Claritin) and cetirizine (Zyrtec), and are possibly even more effective than allergy shots. They have no effect on itchy eyes, however.

Nasal-Spray Brands. Corticosteroids available in nasal spray form include:

Triamcinolone (Nasacort). Approved for children over age 6.
Mometasone furoate (Nasonex). Approved for use in patients age 3 and older.
Fluticasone (Flonase, Flounce, generic). Approved for children over age 4.
Beclomethasone (Beconase, Vancenase), flunisolide (Nasalide), and budesonide (Rhinocort). Approved for children over age 6.
Ciclesonide (Omnaris). Approved for patients age 12 and older.

Side Effects. Corticosteroids are powerful anti-inflammatory drugs. Although oral steroids can have many side effects, the nasal-spray form affects only local areas and has less risk for widespread side effects unless the drug is used excessively. Side effects of nasal steroids may include:

Dryness, burning, stinging in the nasal passage
Sneezing
Headaches and nosebleed (uncommon but should be reported to your doctor immediately)

Possible Long-Term Complications. All corticosteroids suppress stress hormones. This effect is known to produce some serious long-term complications in people who take oral steroids. Researchers have found far fewer concerns with nasal administration or inhaled forms, but there may be certain problems:

Effect on growth. The major concern for children is whether nasal steroids, like other forms of steroids, will adversely affect growth. Studies report either a temporary and slight (about half an inch) early effect on growth or no effect at all.
Effect on eyes. Glaucoma is a known side effect of oral steroids. Some ophthalmologists have observed higher pressure in the eye (a sign of glaucoma) in some patients taking nasal steroid sprays. (Studies have found no increased risk for cataracts in young people who have taken intranasal steroids). The eye pressure appears to return to normal after stopping the steroid, but periodic eye examinations are advised.
Use during pregnancy. Steroids appear to be safe during pregnancy, but pregnant women should talk to their doctor about other options before taking them.
Nasal passage injury. Steroid sprays may injure the nasal septum (the bony area that separates the nasal passage) if the spray is directed onto it. This complication is very rare.
Lower resistance to infection. People with any infectious disease or injury in the nose should not take these drugs until the disease or wound has been treated and cured.

Cromolyn serves as both an anti-inflammatory drug and a specific blocker for allergens. The standard cromolyn nasal spray (Nasalcrom) is not as effective as steroid nasal sprays but does work well for many people with mild allergies. It is one of the preferred first-line therapies for pregnant women with mild allergic rhinitis. It may take up to 3 weeks to experience full benefit.

Side Effects. Cromolyn has no major side effects, but minor ones include nasal congestion, coughing, sneezing, wheezing, nausea, nosebleeds, and dry throat. The spray can cause burning or irritation.

Leukotriene-antagonists are oral drugs that block leukotrienes, powerful immune system factors that are important in causing airway constriction and mucus production in allergy-related asthma. Leukotriene-antagonists include zafirlukast (Accolate), montelukast (Singulair), zileuton (Ziflo), and pranlukast (Ultair, Onon). These drugs are mainly used to treat asthma. Montelukast was approved in 2003 to treat seasonal allergies, and in 2005 to treat indoor allergies.

Immunotherapy

Immunotherapy (commonly referred to as "allergy shots") is a safe and effective treatment for patients with allergies. It is based on the premise that people who receive injections of a specific allergen will lose sensitivity to that allergen. The most common allergens for which shots are given are house dust, cat dander, grass pollen, and mold.

Immunotherapy benefits include:

Targeting the specific allergen.
Reducing sensitivity in airways in the lungs as well as in the upper airways.
Preventing the development of new allergies in children.
Reducing asthma symptoms and the use of asthma medications in patients with known allergies. Research suggests it may also help prevent the development of asthma in children with allergies.

Candidates for Immunotherapy. Immunotherapy may be given to anyone over age 7 whose allergies are severe and who do not respond to medication. Many experts agree that immunotherapy should be considered as soon as possible for children with asthma and allergies. Immunotherapy is safe for pregnant women who are already receiving it, although half-strength doses are generally recommended, and it should not be started during pregnancy.

Individuals at Risk for Complications. People who should probably avoid immunotherapy include those who have:

An extreme response to skin tests (this may predict an allergic reaction).
Wheezing.
Uncontrolled severe asthma or lung disease.
Patients taking certain medications (such as beta-blockers).
The health status of anyone should be determined before starting treatment.

The major downside to immunotherapy is that it requires a prolonged course of weekly injections. The process generally includes:

Injections of diluted extracts of the allergen are given on a regular schedule, usually twice a week to weekly at first, then in increasing doses until a maintenance dose has been reached. It usually takes several months and may take up to 3 years to reach a maintenance dose.
At that time, intervals between shots can be 2 - 4 weeks, and the treatment is continued for another 3 - 5 years.
Patients can experience some relief within 3 - 6 months. If there is no benefit within 12 - 18 months, discontinue the shots.

After stopping immunotherapy, about a third of allergy sufferers no longer have any symptoms, a third have improved symptoms, and a third relapse.

The use of an injection series is effective, but patients often fail to comply with the regimens. Some other schedules and delivery methods are being investigated that might make the program easier and less distressing.

Rush Immunotherapy. Investigators are studying "rush immunotherapy," in which patients achieve the full maintenance dose with several shots a day over a period of 3 - 5 days. Rush therapy uses modifications that reduce the risk of severe reactions to excessive doses. Studies suggest that it is effective and safe, with few side effects other than itching. Patients must be monitored closely during this period, however, for severe reactions.

Oral Forms. Trials are underway to test oral forms of immunotherapy as an alternative to allergy shots. These methods include using a pill taken by mouth or a sublingual (under-the-tongue) tablet. Although oral and sublingual immunotherapy is prescribed in many countries in Europe and South America, it is not approved in the United States and is not considered accepted therapy at this time.

Injections for ragweed and, sometimes, dust mites have higher risks for side effects than other allergy shots. If complications or allergic reactions develop, they usually occur within 20 minutes, although some can develop up to 2 hours after the shot is given.

Side effects of immunotherapy include:

General itching, swelling, red eyes, hives, soreness at the injection site.
Less common side effects are low blood pressure, asthma worsening, or difficulty breathing. This is due to an extreme hypersensitivity response called anaphylaxis. It can also occur if excessive doses are given.
In rare cases, particularly because of excessive doses or if a patient has a serious lung problem, severe reactions can occur, which can be life threatening.
Premedicating patients with antihistamines and corticosteroids may help reduce the risk of reactions to immunotherapy, although this could mask early warning signs.

In a 10-year study, the incidence of any adverse effect was less than two-tenths of 1%, and the great majority of events were mild. The risk for a fatal response is estimated to be 1 in 63 million injections. (As a comparison, the risk for a fatal reaction to penicillin is much higher, 1 in 7.5 million injections.)

Vaccines. Of particular interest is the development of immunotherapeutic vaccines that use more specific targets to produce an insensitivity to allergens. One such vaccine uses a small protein from the allergen, which is injected into the patient. Other vaccines under investigation are those that use the allergen's genetic material (its DNA) to promote tolerance to the allergen. In a promising 2006 pilot study, patients who received 6 weekly injections of a DNA-based experimental ragweed vaccine had symptom reductions that lasted a year later into a second ragweed season. Researchers will be testing this vaccine in further clinical trials.

Monoclonal Antibodies. Monoclonal antibodies (MAb) are genetically-developed antibodies that are designed to target and attack very specific factors. A MAb known as omalizumab (Xolair) prevents the antibody immunoglobulin E (IgE) from triggering the inflammatory events that lead to allergies. Studies in recent years have suggested that omalizumab may help reduce symptoms and improve quality of life for patients with non-seasonal allergic rhinitis. A 2006 study suggested that treatment with omalizumab before and during ragweed allergy shots may help reduce immunotherapy side effects. The drug is currently approved for asthma. In 2007, the FDA warned that omalizumab may cause a life-threatening allergic reaction (anaphylaxis) in some patients.

Prevention

People with existing allergies should avoid irritants or allergens. These triggers include:

Pollen. This is the primary cause of allergic rhinitis.
Dust mites, specifically mite feces, which are coated with enzymes that contain a powerful allergen. These are the primary allergens inside the home.
Animal dander (flakes of skin) and hair from cats, house mice, and dogs. House mice are proving to be significant sources of allergens, particularly in urban children.
Molds.
Fungi.
Cockroaches are major asthma triggers and may reduce lung function even in people without a history of asthma.
Some research suggests that alcohol intake may influence allergy severity. One study found that as little as one drink a day is enough to worsen dust mite allergies.
Some studies suggest that early exposure to some of these allergens, including dust mites and pets, may actually prevent allergies from developing in children.

Controlling Pets. People who already have pets and are not allergic to them are probably at low risk for developing such allergies later on. When children are exposed to more than one dog or cat during their first year, they have a much lower risk for not only pet allergies but also seasonal allergies and asthma. (Pet exposure does not protect them from other allergens, notably dust mites and cockroaches).

In children who have an existing allergy to pets, however, the pets should be given away or kept outside. If this isn't possible, they should at least be confined to carpet-free areas outside the bedroom. Cats harbor significant allergens, which can even be carried on clothing. Dogs usually present fewer problems. Washing animals once a week can reduce allergens. Dry shampoos, such as Allerpet, that remove allergens from skin and fur and are now available for both cats and dogs and are easier to use than wet shampoos.

For small children, stuffed animals might serve as a comforting replacement, although they might harbor dust mites. Putting stuffed animals in the freezer for 24 hours before washing them kills the dust mites. For best effect, this process should be done weekly.

Preventing Exposure to Cigarette and Cooking Smoke. Parents who smoke should quit. Studies show that exposure to second-hand smoke in the home increases the risk for asthma and asthma-related emergency room visits in children. [For help in quitting, see In-Depth Report # 41: Smoking.]

Controlling Dust. Spray furniture polish is very effective for reducing both dust and allergens. Air cleaners, filters for air conditioners, and vacuum cleaners with High Efficiency Particulate Air (HEPA) filters can help remove particles and small allergens found indoors. Neither vacuuming nor the use of anti-mite carpet shampoo, however, is effective in removing mites in house dust. Vacuuming actually stirs up both mites and cat allergens. People with these types of allergies should avoid having carpets or rugs in their homes.

Bedding and Curtains. Many experts recommend reducing exposure to dust mites by enclosing mattresses and pillows in semipermeable coverings. (Vinyl mattress covers limit airflow and may worsen, or even cause, asthma in children.) However, several 2005 studies suggested that such covers do not prevent allergies or asthma. Curtains should be replaced with shades or blinds and bedding washed using the highest water temperature setting.

Reducing Humidity in the House. Dust mites thrive in humidity, and damp houses increase the risk for mold. On-going humidifiers can worsen the problem. If they are used, humidity levels should not exceed 40%, and humidifiers should be cleaned daily with a vinegar solution.

Exterminating Pests (Cockroaches and Mice). Use professional exterminators to eliminate cockroaches. (One study reported that ridding a home of cockroaches and cleaning the house using standard housecleaning techniques failed to eliminate the cockroach allergens themselves.) Exterminate mice and attempt to remove all dust, which might contain mouse urine and dander.

Avoiding Outdoor Allergens. The following are some recommendations for avoiding allergens outside:

Start taking allergy medications 1 - 2 weeks before ragweed season begins. Be sure to take allergy medications before going outside. If regular medications do not work, ask your doctor about allergy shots.
Camping and hiking trips should not be scheduled during times of high pollen count (May and June for grass pollen and September to October for ragweed).
Patients who are allergic should avoid barns, hay, raking leaves, and mowing grass. (A mask can be worn during outdoor chores to help reduce pollen exposure.)
Sunglasses can help prevent pollen from getting into eyes.
After being outdoors, clean off pollen residue by bathing, washing hair and clothes, and using a nasal salt water rinse.

Some evidence suggests that people with allergic rhinitis and asthma may benefit from a diet rich in omega-3 fatty acids (found in fish, almonds, walnuts, pumpkin, and flax seeds) and fruits and vegetables (at least five servings a day). Some studies also suggest reducing sodium, trans fatty acids (hydrogenated fats found in commercial products and baked goods), and omega-6 fatty acids (found in most vegetable oils). Investigators are also studying probiotics -- so-called good bacteria, such as lactobacillus and bifidobacterium, which can be obtained in supplements.

Resources

www.aaaai.org -- American Academy of Allergy, Asthma & Immunology
www.acaai.org -- American College of Allergy, Asthma & Immunology
www.niaid.nih.gov -- National Institute of Allergy and Infectious Diseases
www.njc.org -- National Jewish Medical and Research Center
www.lungusa.org -- The American Lung Association

References

Bower JH, Maraganore DM, Peterson BJ, Ahlskog JE, Rocca WA. Immunologic diseases, anti-inflammatory drugs, and Parkinson disease: a case-control study. Neurology. 2006 Aug 8;67(3):494-6.

Calderon M, Alves B, Jacobson M, Hurwitz B, Sheikh A, Durham S. Allergen injection immunotherapy for seasonal allergic rhinitis. Cochrane Database Syst Rev. 2007 Jan 24;(1):CD001936.

Creticos PS, Schroeder JT, Hamilton RG, Balcer-Whaley SL, Khattignavong AP, Lindblad R, et al. Immunotherapy with a ragweed-toll-like receptor 9 agonist vaccine for allergic rhinitis. N Engl J Med. 2006 Oct 5;355(14):1445-55.

Leger D, Annesi-Maesano I, Carat F, Rugina M, Chanal I, Pribil C, et al. Allergic rhinitis and its consequences on quality of sleep: An unexplored area. Arch Intern Med. 2006 Sep 18;166(16):1744-8.

Review Date:
3/22/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Asthma in children and adolescents

FitSugar — Wed, 08 Oct 2008 17:35:28 -0700

In This Report

Highlights
Introduction
Causes
Prognosis
Risk Factors
Symptoms
Diagnosis
Treatment
Quick-Relief Medications...
Long-Term Relief Medication...
Other Treatments
Managing Asthma
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Drug Warning

In 2007, the FDA requested the manufacturers of omalizumab (Xolair) to include a “boxed warning” emphasizing that this drug may cause a severe and life-threatening allergic reaction (anaphylaxis). Health care providers need to carefully observe patients for 2 hours after they receive an omalizumab injection. However, because an allergic reaction can occur up to 24 hours after the injection, patients need to know the signs and symptoms of anaphylaxis and how to self-administer emergency treatment. Omalizumab is approved for patients ages 12 and older who have moderate-to-severe asthma related to allergies.

Drug Approval

In 2006, budesonide/formoterol (Symbicort) was approved for patients age 12 years and older. Symbicort combines a corticosteroid and a long-acting beta2-agonist into a single inhaler.

Inhaled Corticosteroids

Inhaled corticosteroids may help reduce wheezing in young children with breathing problems, but they do not help prevent the development of asthma, according to several 2006 studies in the New England Journal of Medicine.
Inhaled corticosteroids work better than a corticosteroid/long-acting beta2-agonist combination or a leukotrine receptor antagonist drug in treating children with mild-to-moderate asthma, suggests a 2007 study in the Journal of Allergy and Clinical Immunology.

Long-Acting Beta2-Agonists

Long-acting beta2-agonist drugs such as salmeterol (Serevent Diskus) and formoterol (Foradil Aerolizer) may worsen asthma symptom severity and increase the risk for asthma-related death, indicates a 2006 review in the Annals of Internal Medicine.
Products that contain salmeterol and formoterol now have strengthened warning labels detailing these risks.

Childhood Asthma Statistics

Asthma death rates among children have largely declined since 1999 while doctors’ office visits for asthma treatment have more than doubled, indicates a recent report from the U.S. Centers for Disease Control and Prevention.

Introduction

The word asthma originates from an ancient Greek word meaning panting. Essentially, asthma is an inability to breathe properly. When any person inhales, the air travels through the following structures:

Air passes into the lungs and flows through progressively smaller airways called bronchioles. The lungs contain millions of these airways.
All bronchioles lead to alveoli, which are microscopic sacs where oxygen and carbon dioxide are exchanged.

The major features of the lungs include the bronchi, the bronchioles, and the alveoli. The alveoli are the microscopic blood vessel-lined sacks in which oxygen and carbon dioxide gas are exchanged.

Asthma is a chronic condition in which these airways undergo changes when stimulated by allergens or other environmental triggers. Such changes appear to be two specific responses:

The hyperreactive response (also called hyperresponsiveness)
The inflammatory response

These actions in the airway cause patients to cough, wheeze, and experience shortness of breath (dyspnea), the classic symptoms of asthma.

In the hyperreactive response, smooth muscles in the airways constrict and narrow excessively in response to inhaled allergens or other irritants. Airways in everyone's lungs respond by constricting when exposed to allergens or irritants but there are major differences in the hyperreactive response that occurs in people with asthma:

When people without asthma breathe in and out deeply, the airways relax and open in order to rid the lungs of the irritant.
When people with asthma try to take those same deep breaths, their airways do not relax but instead narrow, causing the patients to pant for breath. Smooth muscles in the airways of people with asthma may have a defect, perhaps a deficiency in a critical chemical that prevents the muscles from relaxing.

The hyperreactive stage is followed by the inflammatory response, which generally contributes to asthma in the following way:

The immune system responds to allergens or other environmental triggers by delivering white blood cells and other immune factors to the airways.
These so-called inflammatory factors cause the airways to swell, fill with fluid, and produce a thick sticky mucus.

Click the icon to see an image of a normal versus asthmatic bronchiole.

This combination of events results in wheezing, breathlessness, inability to exhale properly, and a phlegm-producing cough.

Inflammation appears to be present in the lungs of all patients with asthma, even those with mild cases, and plays a key role in all forms of the disease.

Causes

Asthma occurs in about 5 million American children. Each year about 200,000 of them are hospitalized. It is the most common chronic childhood illness. About half of all cases of asthma develop before the age of 10, and about 80% of patients develop symptoms before they are 5 years old.

The mechanisms that cause asthma are complex and vary among population groups and even individuals. For example, asthma in children is highly associated with allergies. However, only a minority of children with allergies have asthma, and allergic response cannot explain all cases of asthma. Other factors, such as genetics or environmental conditions are probably involved in the development of asthma. Most likely, several genes combine to make a child susceptible to environmental triggers, not only allergens but also possibly infections, dietary patterns, or air pollution. Physical factors, particularly having smaller lungs, affect the chances for later asthma.

Asthma and allergies often coexist, and the allergic response plays a strong role in childhood asthma. About 70 - 85% of children with asthma also have allergies. Some studies suggest that children who have allergies are also at greater risk for developing asthma as adults. A 2006 study found that children who are allergic to dust mites are three times more likely to later develop asthma than children who were not allergic.

However, the evidence is clearly mixed. Several other 2006 studies suggested that avoiding dust mites does not help prevent asthma and, in fact, early exposure to dust mites may even protect children from developing asthma and allergic responses. Some experts think that giving immunotherapy (“allergy shots”) to children with allergies may help prevent asthma development.

An asthma attack can be induced or aggravated by direct irritants to the lungs. Studies indicate that the more indoor allergens a child is allergic to, the higher the risk for severe asthma. Important irritants or allergens include the following:

Dust mites, specifically mite feces, which are coated with enzymes that contain a powerful allergen. These are the primary allergens in the home.
Animal dander. Cats harbor significant allergens, which can even be carried on clothing; dogs usually present fewer problems.
Molds.
Cockroaches. Cockroaches are major asthma triggers and may reduce lung function even in people without a history of asthma.
Pollen. An asthma attack from an allergic response to pollen is more likely to occur during extreme air changes, such as thunderstorms. Major weather changes, such as El Nino, can affect the timing of allergy seasons because they cause seasonal changes (and pollen) to start earlier.
Food allergies. About 8 - 10% of children with asthma also have food allergies. These children also appear to have a high risk for very serious reactions to such foods. In infants and toddlers, allergy to eggs appears to be a predictor of asthma.
Fossil Fuels. Certain chemicals may trigger allergic rhinitis. Some experts believe that refined fossil fuels, such as diesel fuel and particularly kerosene, may be important triggers for allergic rhinitis. In people who already have allergies or asthma, exposure to such fossil fuels may worsen symptoms.

The Allergic Response. The allergic process, called atopy, and its connection to asthma are not completely understood. It involves various airborne allergens or other triggers that set off a cascade of events in the immune system leading to inflammation and hyperreactivity in the airways. One description is as follows:

The conductor in an orchestra of immune factors that contribute to allergies and asthma appears to be a category of white blood cells known as helper T cells, in particular a subgroup called Th2 cells.
Th2 cells overproduce interleukins (ILs), immune factors that are molecular members of a family called cytokines, which are involved in the inflammatory process.
Interleukins 4, 9, and 13, for example, may be responsible for a first-phase asthma attack. These interleukins stimulate the production and release of antibody groups known as immunoglobulin E (IgE). (People with both asthma and allergies appear to have a genetic predisposition for overproducing IgE.)
During an allergic attack, these IgE antibodies can bind to special cells in the immune system called mast cells, which are generally concentrated in the lungs, skin, and mucous membranes. This bond triggers the release of a number of active chemicals, importantly potent molecules known as leukotrienes. These chemicals cause airway spasms, overproduce mucus, and activate nerve endings in the airway lining.
Another cytokine, interleukin 5, appears to contribute to a late-phase inflammatory response. This interleukin attracts white blood cells known as eosinophils. These cells accumulate and remain in the airways after the first attack. They persist for weeks and mediate the release of other damaging particles that remain in the airways.

Researchers are investigating the role that T cells play in asthma. T cells are white blood cells that are involved in the immune response. Researchers had focused on the T cell called type 2 helper (ThH2) cells. However, a 2006 breakthrough study in the New England Journal of Medicine suggested that a different type of T cell may play a stronger role in asthma than previously thought.

Researchers discovered that these cells, called natural killer T cells, are far more common in the lungs of people with asthma than in the lungs of healthy people. Natural killer T cells are very rare, but researchers found them in 60% of people with moderate-to-severe persistent asthma. While this research is preliminary, it may explain why corticosteroid drugs do not work well for some patients with asthma: Steroid drugs target Th2 and other inflammatory cells, not natural killer T cells. Researchers think that further investigation of natural killer T cells may lead the way to new types of asthma drugs. If these cells prove to be involved in asthma, then drugs that eliminate them might become an important new treatment.

Over the course of years the repetition of the inflammatory events involved in asthma can cause irreversible structural and functional changes in the airways, a process called remodeling. The remodeled airways are persistently narrow and can cause chronic asthma. Researchers are trying to determine how this process occurs:

Interleukins. Some researchers are looking at potent immune factors, including interleukins 11 and 13. They have been linked to a number of processes possibly involved in remodeling, including scarring in the airways and overgrowth of cells in the smooth muscles that line the airways.

Growth Factors. Compounds known as vascular endothelial growth factor (VEGF) have been observed in the airways of patients with asthma. VEGF is a powerful promoter of cell growth in blood vessel linings and some researchers believe it may be major factor in remodeling.

About one-third of all persons with asthma share this condition with another member of their immediate family. Asthma may be more likely to be passed to children from the mother than from the father. Both allergies and asthma are strongly associated with hereditary factors, sharing certain genetic markers, but they are not always inherited together.

Research on the genetics of these conditions is confusing. Of some significant promise, researchers have identified a gene (ADAM33), which has been linked to asthma. The gene regulates one of the enzymes called metalloproteases, which are involved with the smooth muscle in the airway. A mutation of this gene could play a role in airway changes that occur after inflammation.

The role of early childhood respiratory and intestinal infections is very complex. Viral respiratory infections certainly worsen existing asthma, but the most common ones are unlikely to be causes of childhood asthma. In fact, early respiratory and intestinal infections may offer some protection against asthma.

Early Respiratory Infections as Causes of Asthma. Studies suggest that most respiratory infections are not important causes of asthma in children, except in certain cases. An important exception is the respiratory syncytial virus (RSV), which has been implicated in the development of asthma. RSV is the major viral cause of infant pneumonia. Studies also indicate that infants who have reduced lung function within a few days after birth are at increased risk of developing asthma by the time they are 10 years old.

Common Respiratory Infections Worsen Asthma. Common respiratory infections viruses that cause colds (such as the rhinovirus) may in some cases be associated with the development of asthma. A 2007 study suggested that children who have a wheezing rhinovirus during infancy are at increased risk for developing asthma by age 6. Even if these viruses do not directly cause asthma, they can worsen asthma in children who already have it. Rhinovirus has been reported to be the most common infection associated with asthma attacks. In one study, it was associated with 61% of asthma worsening in children. Some research suggests that colds promote inflammation in patients with existing asthma and increase the intensity of airway responsiveness for weeks.

The Hygiene Theory: Early Infections as Protection Against Asthma. Another blames the dramatic increase in asthma on the reductions in childhood infections that have occurred with modern hygiene and antibiotic use. The basic theory rests on the idea that infections stimulate production of specific immune factors called Th1 cells. As these cells build up, they replace other immune factors called Th2 cells, which react to allergens -- a less serious threat to the body. Without infections to stimulate the production of the Th1 infection fighters, the Th2 allergen fighters are not replaced, and they persist at high levels, making the growing child more susceptible to allergies and asthma.

A number of different studies support this theory:

Some studies suggest that being part of a large family or attending day care increases the risk for early respiratory infections but reduces the risk of childhood asthma. The occasional cold, then, may be protective.
In one study, researchers measured levels of bacterial byproducts called endotoxins in the mattress dust of 812 children. Those with the highest levels had 80% lower rates in allergies and asthma.
Another study further found a strong association between allergy development and the absence of certain beneficial bacteria (called probiotics) carried in the infant's intestines. Infants who were born in more hygienic environments tended to lack these bacteria. Antibiotic overuse and modern hygiene may be reducing these helpful organisms. (Probiotics can be obtained in active yogurt cultures and in supplements, which are being studied for protection.)

The standard vaccinations against serious childhood infections, according to several important studies, pose no risk for asthma. One of the studies even reported some lower risk for asthma and allergies in the second and third years after vaccinations. Infections killed thousands of children every year before immunization became widespread. Asthma, although serious, is rarely fatal in children. No one should stop giving their children vaccinations against childhood killers.

GERD. At least half of patients with asthma also have gastroesophageal reflux disease (GERD), the cause of heartburn. It is not entirely clear which condition causes the other or whether they are both due to common factors.

Heartburn is a condition where the acidic stomach contents back up into the esophagus causing pain in the chest area. This reflux usually occurs because the sphincter muscle between the esophagus and stomach is weakened. Standing or sitting after a meal can help reduce the reflux which causes heartburn. Continuous irritation of the esophagus lining as in gastroesophageal reflux disease is a risk factor for the development of adenocarcinoma.

Some theories for the causal connection between GERD and asthma are:

Acid leaking from the lower esophagus in GERD stimulates the vagus nerve, which runs through the gastrointestinal tract. This stimulated nerve, in turn, triggers the nearby airways in the lung to constrict, causing asthma symptoms.
Acid back-up that reaches the mouth may be inhaled into the airways (aspirated). Here, the acid triggers a reaction in the airways that cause asthma symptoms.

GERD is sometimes hard to detect and might be suspected as a contributor in the following patients:

Those who do not respond to asthma treatments.
Those whose asthma attacks follow episodes of heartburn.
Those whose attacks are worse after eating or exercise.
Those whose coughs follow episodes of acid reflux. (One study found that GERD was associated with about half of the episodes of coughs and wheezes in patients with asthma.)

Treating GERD symptoms with anti-acid drugs may resolve asthma in some (but not all) patients who share both conditions. A small 2005 observational study found that while GERD was common in patients with asthma, treatment of GERD had no effect on asthma symptoms. [See In-Depth Report #85: Heartburn and gastroesophageal reflux disease.]

Sinusitis. Almost half of children and adults with allergic asthma have sinus abnormalities, and in various studies, between 17 - 30% of patients with asthma develop true sinusitis. The presence of sinusitis, however, does not appear to increase the severity of asthma.

Click the icon to see an image of sinusitis.

Parental Migraines and Childhood Asthma. Some studies have reported a link between childhood asthma and parental migraines, with one small study suggesting that children are about five times more likely to develop asthma if their parents have a history of migraines.

Exercise-induced asthma (EIA) is a limited form of asthma in which exercise triggers coughing, wheezing, or shortness of breath.

About 10% of adults and some fewer children have aspirin-induced asthma (AIA). With this condition, asthma gets worse when patients take aspirin. Aspirin is one of the drugs known as nonsteroidal anti-inflammatory drugs (NSAIDs). Although aspirin is used to reduce inflammation in other disorders, it appears to have the opposite effect in many asthma cases. It is not wholly known why this occurs. AIA often develops after a viral infection. It is a particularly severe asthmatic condition and is associated with up to 25% of asthma-related hospitalizations. In about 5% of cases, aspirin is responsible for a syndrome that involves multiple attacks of asthma, sinusitis, and nasal congestion. Such patients also often have polyps (small benign growths) in the nasal passages.

Patients with aspirin-induced asthma (AIA) should avoid aspirin and most likely NSAIDs, including ibuprofen (Advil) and naproxen (Aleve).

Acetaminophen (Tylenol) has been the traditional alternative for relief of minor pain for patients who are aspirin-sensitive. Unfortunately, recent evidence has muddied these recommendations. Moreover, some asthmatic episodes have been linked to high consumption of acetaminophen among adults. And a study of children with asthma reported that those who took ibuprofen were less likely to be hospitalized for asthma than those taking acetaminophen. This is of particular concern, since acetaminophen is the pain reliever of choice in small children.

Asthma occurs primarily at night (nocturnal asthma) in as many as 75% of patients with the condition. Attacks often occur between 2 - 4 a.m. Factors that might play role in nocturnal asthma may include one or more of the following:

Chemical and temperature changes in the body during the night that increase inflammation and narrowing of the airways
Delayed allergic responses from exposure to allergens during the day
The wearing off of inhaled medications toward the early morning
An increase in acid reflux (back up of stomach acid) that causes airways to narrow
Postnasal drip that occurs during sleep
Conditions relating to sleep, such as sleep apnea or sleeping on one's back, which may worsen any asthma attack that occurs at night

Some experts believe that nocturnal asthma may actually be a unique form of asthma with its own specific biologic mechanisms that occur only at night and which reduce natural steroid hormones (which block inflammation).

Exercise-induced asthma (EIA) is a limited form of asthma in which exercise triggers coughing, wheezing, or shortness of breath. This condition generally occurs in children and young adults, most often during intense exercise in cold dry air. Symptoms are generally most intense about 10 minutes after exercising and then gradually resolve.

EIA is triggered only by exercise and is distinct from ordinary allergic asthma in that it does not produce a long duration of airway activity, as allergic asthma does. (However, some people have both forms of asthma.) People who have only EIA do not appear to require long-term maintenance therapy. A study of military recruits with EIA also reported that the condition does not hinder a person's overall physical performance.

Medications. Cromolyn, a mild anti-inflammatory drug, or short-acting beta2-agonists have been the treatments of choice for preventing EIA. Newer approaches for people who work out regularly include pretreatment with long-acting beta2-agonists, such as salmeterol (Serevent) or the regular use of inhaled corticosteroids.

Hints for Reducing EIA. EIA occurs only after exercise and is more likely to occur with regular paced activities in cold, dry air. The following are some suggestions for reducing its impact:

Warm-up and cool-down periods are important.
Patients with EIA might do better with activities that involve short bursts of exercise (tennis, football) than with exercises involving long-duration regular pacing (cycling, soccer, and distance running).
Breathing through a scarf or through the nose helps warm up the airways.
Restricting dietary salt might help reduce EIA.

Click the icon to see an image of exercise-induced asthma.

Prognosis

Asthma is the third major cause of hospitalization in children under age 15. The condition can be very serious in children, particularly those younger than age 5, because their airways are very narrow.

The severity of asthma is graded as mild intermittent and mild, moderate, and severe persistent. A patient in any of these categories, even mild intermittent, can still experience a severe and even life-threatening attack. According to one report, 30% of asthma deaths occur in patients with mild asthma.

Asthma is rarely fatal in children, with only 187 asthma deaths reported in 2002 in children under age 18. In fact, a 2006 study from the U.S. Centers for Disease Control and Prevention reported that asthma death rates for children have steadily declined since 1999. (During the same time, the number of doctor visits for asthma treatment more than doubled.) Even low mortality numbers are unacceptable, however, since asthma deaths are largely preventable.

Factors associated with an increased risk of death from asthma in children include:

Previous life-threatening episodes of asthma
Lack of adequate and ongoing health care. (Most likely the reason for the higher fatalities rates in minority children.)
Significant behavioral problems
Underestimating the severity of an acute attack poses the greatest threat. Unfortunately, one study of children found that nearly 40% of them were unaware of asthmatic symptoms when they occurred.

African American children have more than six times the death rate of Caucasians in the age groups of 4 years and younger and 15 - 24 years. Hispanic children also have a higher risk.

The following signs and symptoms may indicate a life-threatening situation:

As the chest labors to bring enough air into the lungs, breathing often becomes shallow.
Lacking sufficient oxygen, the skin becomes bluish.
The flesh around the ribs of the chest appears to be sucked in.
The patient may begin to lose consciousness.

Asthma often progresses very slowly to a serious condition or may develop to a fatal or near-fatal attack within a few minutes. It is very difficult to predict when an attack will become very serious. Early symptoms or lack thereof do not always reflect the ultimate severity of an attack. Some studies even suggest that people at high risk for fatal or near-fatal asthma attacks are those with poor awareness of their own reduced ability to breathe and who are slow in seeking help. Monitoring peak flow rates is, therefore, an important management component, since it provides a more accurate assessment of lung function than symptoms alone.

In a 2003 study, researchers followed people with asthma for longer than 30 years. About a third of children had outgrown their asthma in adulthood. In general, the more severe the childhood asthma, the greater the likelihood that it will persist. For example, only 23% of children who experienced wheezy bronchitis (wheezing during respiratory infections) suffered from frequent or persistent asthma in adulthood.

There is evidence that severe asthma can cause long-lasting damage and possibly permanent scarring in some patients. The risk for such injury is highest, however, when asthma strikes children in the first 3 - 5 years. There does not appear to be any significant risk for long-term lung damage for children who develop mild-to-moderate persistent asthma between ages 5 - 12. Children adapt well to living with asthma, and even with severe asthma they can function as well as healthy children in virtually all areas of life.

Studies are mixed over the effects of emotional disorders on the severity of asthma. One study indicated that parents of children with asthma may suffer greater psychological stress than their children. A 2000 study reported that mild-to-moderate asthma does not significantly affect the psychological well-being of most children ages 5 - 12. Teenagers and preteens may have particular difficulty coping with what they perceive as the social stigma of asthma. Parents and older children should not hesitate to seek help from support groups, doctors, friends, or family members. Support programs may help children to better manage their asthma and even reduce hospitalization.

Although there have been few studies on the effects of asthma on schooling, a 2000 study reported that nocturnal (nighttime) asthma affected school attendance and performance in children and work attendance in their parents.

Risk Factors

Asthma affects about 5 million American children between the ages of 5 - 14. Asthma has dramatically increased worldwide over the last few decades, in both developed and developing countries. From 1980 - 1994, asthma increased 160% in American children younger than 4 years and has also dramatically risen worldwide. Experts are puzzling over the cause of this phenomenon. Possible causes and risk factors that are suspects in the dramatic rise in asthma in children include:

Survival rates are now higher in low-birth-weight babies, who may be more susceptible to asthma.
Declining rates in nursing may be a contributor. Breast milk contains important anti-inflammatory substances, such as omega-3 fatty acids, which might protect against asthma.
Western dietary habits (which commonly include more fast foods and less fruits, vegetables, fiber, minerals, and other nutrients) may contribute to the development of childhood asthma.
Children are spending more time indoors watching television, playing video games, or using the computer and are, therefore, overexposed to indoor allergens.
The trend of making homes more energy-efficient may result in dust mites being trapped inside them.

Among younger children, asthma develops twice as frequently in boys as in girls, but after puberty it may be more common in girls.

Urban Life. Urban life is strongly associated with a higher risk. Although poverty plays a significant role, urban life has been associated with a higher risk for asthma in any income group and among both children and adults. In some urban areas, as many as 25% of children have asthma or show signs of wheezing. In fact, it may be greatly underdiagnosed in city children. A 1999 study reported that almost a third of children in inner-city kindergartens had asthma symptoms without a diagnosis of the disorder; 10% had actually been diagnosed with asthma, mainly because their symptoms were severe.

Ethnicity. Since 1980, asthma rates have risen the most dramatically among African American children, and they have significantly higher rates of asthma than Caucasian children. Hispanic children are also at higher risk. Both groups of minority children are more likely to have fatal asthma than Caucasian children.

Some studies indicate that the difference in risk exists simply because African Americans and other minority groups are more likely to live in urban areas. Poverty and lack of access to health care also play a role. However, Caucasian children who live in cities also face a high risk for asthma, and rural African American children do not.

Urban life and socioeconomic factors, however, may not fully explain the ethnic disparity.

Low Birth Weight. Infants of low birth weight are at higher risk for lung problems and asthma.

Winter Birth. Children born in the winter may have a greater risk for asthmatic allergies to cockroaches than children born at other times of the year.

Vitamin D. A 2006 study suggested a link between vitamin D intake during pregnancy and development of early childhood asthma. Pregnant women who had a higher intake of vitamin D were less likely to give birth to children who developed asthma.

Breast Feeding. Most studies on breastfeeding report some protection against wheezing and asthma in the first year of life. Breastfeeding has many other benefits for the child as well. The American Academy of Pediatrics recommends exclusively breastfeeding for the child's first 6 months of life.

Complications of Pregnancy. According to a 2000 study, complications of pregnancy, specifically those involving the mother's uterus (such as post-birth hemorrhage, pre-term contractions, insufficient placenta, and restricted growth of the uterus), are associated with an increased risk of childhood asthma. Another study reported that delivery procedures such as Cesarean section, the use of vacuum extraction or forceps also raised the risk of childhood asthma.

In both adults and children, the incidence of obesity and asthma has been increasing over recent years. Studies report a strong association between the two conditions. Some experts suggest that excess weight pressing on the lungs may trigger the hyperreactive response in the airways typical of asthma. Others believe that asthma leads to obesity by inhibiting physical activity, although several studies have found no difference in activity levels between people with or without asthma. Some studies suggest that many obese people may be misdiagnosed as having asthma when they are simply short of breath, possibly because of the increased effort required for breathing.

In any case, there is evidence that losing weight can relieve asthma symptoms. Some evidence also suggests that people who are overweight (body mass index greater than 25) have more difficulty getting their asthma under control. Weight loss in anyone who is obese and has asthma or shortness of breath reduces airway obstruction and improves lung function. [See In-Depth Report #53: Weight control and diet.].

Damp Homes. Studies suggest that children who live in damp homes have a much higher risk for asthma.

Mental Health. Research indicates that poor mental health of parents and children are significant predictors of more severe symptoms in childhood asthma. A 2000 study suggested that high stress levels can predict the onset and severity of asthma in children genetically at risk for the condition.

Symptoms

In children with asthmatic symptoms, it is important to first consider as a possible cause inhaled foreign objects such as peanuts; viral infections such as croup; and bacterial infections, which may be accompanied by high fever and progress rapidly. Any child who has frequent coughing or respiratory infections should be checked for asthma.

The classic symptoms of an asthma attack include:

Wheezing when breathing out is nearly always present during an attack. Usually the attack begins with wheezing and rapid breathing, and, as it becomes more severe, all breathing muscles become visibly active.
Shortness of breath (dyspnea). Shortness of breath is a major source of distress in patients with asthma, although severe dyspnea does not always reflect a serious attack or reduced lung function.
Coughing. In some people, the first symptom of asthma is a nonproductive cough.
Chest tightness or pain. Initial chest tightness without any other symptoms may be an early indicator of a serious attack.
Neck muscles may tighten, and talking may become difficult or impossible.
Rapid heart rate
Sweating
Chest pain occurs in about 75% of patients. It can be very severe, although its intensity is not necessarily related to the severity of the asthma attack itself.

The end of an attack is often marked by a cough that produces thick, stringy mucus. After an initial acute attack, inflammation persists for days to weeks, often without symptoms. (The inflammation itself must still be treated, however, because it usually causes relapse.)

Diagnosis

The doctor will consider a diagnosis of asthma if a child has a history of periodic attacks of shortness of breath, coughing, and wheezing, perhaps accompanied by tightness in the chest. The parent should describe the pattern of symptoms and possible precipitating factors, including:

Whether symptoms are more frequent during the spring or fall (allergy seasons)
Whether exercise, a respiratory infection, or exposure to cold air has ever triggered an attack
Any family history of asthma or allergic disorders such as eczema, hives, or hay fever

A number of disorders may cause some or all of the symptoms of asthma. Panic disorder can coincide with asthma or be confused with it. Other diseases that must be considered during diagnosis are pneumonia, bronchitis, severe allergic reactions, psychosomatic illnesses, and certain rare disorders (such as tapeworm and trichomoniasis).

If symptoms and a patient's history are indicative of asthma, the doctor will usually perform tests known as pulmonary function tests to confirm the diagnosis and determine the severity of the disease.

Using a spirometer, an instrument that measures the air taken into and exhaled from the lungs, the doctor will determine several values:

Vital capacity (VC), which is the maximum volume of air that can be inhaled or exhaled.
Peak expiratory flow rate (PEFR), commonly called the peak flow rate, which is the maximum flow rate that can be generated during a forced exhalation.
Forced expiratory volume (FEV1), the maximum volume of air expired in 1 second.

If the airways are obstructed, these measurements will fall. Depending on the results, the doctor will take the following steps:

If measurements fall, the doctor typically asks the patient to inhale a bronchodilator. This drug is used in asthma to open the air passages. The measurements are taken again. If the measurements are more normal, the drug has most likely cleared the airways, and a diagnosis of asthma is strongly suspected.
If measurement results fail to show airway obstruction, but asthma is still suspected, the doctor may perform a challenge test. It involves administering a specific drug (histamine or methacholine) that usually increases airway resistance only when asthma is present.

The patient may be given skin or blood allergy tests, particularly if a specific allergen is suspected and available for testing. Allergy skin tests may be the best predictive test for allergic asthma, although they are not recommended for people with year-round asthma.

One of the most common methods of allergy testing is the scratch test or skin prick test. The test involves placing a small amount of the suspected allergy-causing substance (allergen) on the skin (usually the forearm, upper arm, or the back), and then scratching or pricking the skin so that the allergen is introduced under the skin surface. The skin is observed closely for signs of a reaction, which usually includes swelling and redness of the site. With this test, several suspected allergens can be tested at the same time, and results are usually available within about 20 minutes.

Tests that either rule out other diseases or obtain more information about the causes of asthma include the following:

A complete blood count
Chest and sinus x-rays
Computed tomography (CT) scans. CT scans may be helpful in certain cases, such as for determining wall thickness in airways in patients who are difficult to treat, which could signify a higher risk for lung damage.
Examination of the patient's sputum for eosinophils (white blood cells that in high levels are associated with severe allergic asthma).
Researchers are investigating measurements of certain chemicals in sputum or exhaled air that indicate airway inflammation. Such chemical markers include nitric oxide and hydrogen peroxide. For example, high levels of nitric oxide may prove to be a simple and noninvasive way of diagnosing asthma.

Treatment

Treating an Acute Attack in the Hospital. An acute attack may require hospitalization. Laboratory tests, an electrocardiogram (ECG), and a chest x-ray are performed to determine lung function, oxygen levels, and other indications of severity or rule out other causes. Depending on the results, the following treatments may be given:

Beta2-agonists are the standard therapy. They are typically administered with a nebulizer (a device that administers the drug in a fine spray). Studies suggest, however, that even very small children may be able to use metered-dose inhalers (MDIs), which are just as effective and more convenient than nebulizers. (Intravenous delivery is not recommended in most cases.)
An anticholinergic drug (ipratropium) is sometimes added to improve symptoms.
A corticosteroid (commonly called a steroid) given within the first hour helps reduce the need for hospitalization. Steroids may be administered intravenously, as a shot, or orally. Children may respond well to oral steroids.
Oxygen is usually administered, and can be life saving in severe cases.
Infusions of magnesium sulfate open airways and are an important emergency treatment for adults. Its benefits for children need to be further demonstrated.
In life-threatening situations, the patient may require mechanical ventilation.

Antibiotics are not useful for asthma attacks if there is no strong evidence of the presence of a bacterial infection. Viral infections, most often colds and the flu, are more likely to trigger an asthma attack. In such cases, antibiotics are not helpful and may have adverse effects.

Discharge and Relapse After Hospitalization. It typically takes about 3 - 4 hours to determine if a patient can be safely sent home or if they need to stay. Patients are generally discharged when:

Symptoms are gone or minimal, and
The peak expiratory flow rate is 70% or more of the predicted rate

Despite reasonable precautions, between 12 - 16% of patients relapse within 2 weeks of leaving the hospital. Receiving a steroid shot at discharge or taking an oral corticosteroid for a few days can reduce this risk.

Avoiding allergens, following appropriate drug treatments, and home monitoring are key elements in preventing dangerous asthma attacks and hospitalization. In addition, good communication between the doctor and patient is a key factor in a successful management program.

Medications for asthma fall into two categories:

Rescue Medications. Medications that open the airways (bronchodilators, or inhalers) are used to quickly relieve any moderate or severe asthma attack. These drugs are usually short-acting beta-adrenergic agonists (beta2-agonists). Other drugs used in special cases include corticosteroids taken by mouth and anticholinergic drugs. None of these drugs have any effect on the disease process itself. They are only useful for treating symptoms.
Maintenance Medications. Simply coping with asthma symptoms without also controlling the damaging inflammatory response is a common and serious error. For adults and children over age 5 with moderate-to-severe persistent asthma, experts now recommend inhaled corticosteroids and long-acting beta2-agonists.

Parents can greatly reduce the frequency and severity of their children’s asthma attacks by understanding the difference between coping with asthma attacks and controlling the disease over time. Unfortunately, many patients do not understand the difference between medications that provide rapid, short-term relief and those that are used for long-term symptom control. Many patients with moderate or severe asthma overuse their short-term medications and underuse their corticosteroid medications. The overuse of bronchodilators can have serious consequences; not using steroids can lead to permanent lung damage.

Patients need to understand that asthma symptoms can change quickly over time and that treatment strategies may need to change in response. In 2005, the two leading U.S. allergy associations published joint guidelines on controlling asthma. The guidelines emphasize that asthma treatment decisions need to be made on an individual basis. It is important that patients have a close relationship with their doctor. The doctor needs to evaluate a patient’s asthma symptoms at each visit to determine any need for changes in medication. According to the guidelines, asthma management is classified as either “well-controlled” or “not well-controlled.” The doctor may need to change some medications, or increase or decrease the dosage, depending on whether a child’s asthma is well-controlled or not well-controlled.

These are the signs of well-controlled asthma:

Asthma symptoms occur twice a week or less
Rescue bronchodilator medication is used twice a week or less
Symptoms do not cause nighttime or early morning awakening
Symptoms do not limit work, school, or exercise activities
Peak flow meter readings are normal or the patient’s personal best
Both the doctor and the patient consider the asthma to be well controlled


Classification	Symptom Frequency	Children Age 5 Years and Younger: Recommended Treatment	Children Older Than 5 Years: Recommended Treatment
Mild intermittent	At least 2 days per week. At least 2 nights per month.	No daily medication.	No daily medication. If severe attacks occur, systemic corticosteroids recommended.
Mild Persistent	More than 2 days per week, but less than once per day. More than 2 nights per month.	Preferred treatment: Low-dose inhaled corticosteroids with nebulizer, or MDI with holding chamber with or without face mask. Alternative treatment: Cromolyn or leukotriene-antagonist.	Preferred treatment: Low-dose corticosteroids. Alternative treatment: Cromolyn, leukotriene modifier, nedocromil, OR sustained release theophylline.
Moderate Persistent	Daily daytime symptoms. More than 1 night per week.	Preferred treatment: Low-dose inhaled corticosteroids and long-acting beta2-agonists OR medium-dose inhaled corticosteroids. Alternative treatment: Low-dose inhaled corticosteroids and either leukotriene receptor antagonist or theophylline. If needed (especially if severe attacks occur): Medium-dose inhaled corticosteroids and long-acting beta2-agonists; medium-dose inhaled corticosteroids and either leukotriene receptor antagonist or theophylline.	Preferred treatment: Low-to-medium dose inhaled corticosteroids and long-acting beta2-agonists. Alternative treatment: Low-to-medium dose inhaled corticosteroids and either leukotriene receptor antagonist or theophylline, or increased medium dose inhaled corticosteroids. If needed (especially if severe attacks occur): Increase dosage of medium-dose inhaled corticosteroids with add-on long-acting beta2-agonists. Alternatively, increase dosage of medium-dose inhaled corticosteroids plus either leukotriene receptor antagonist or theophylline.
Severe Persistent	Continual daytime symptoms. Frequent nighttime symptoms.	Preferred treatment: High-dose inhaled corticosteroids and long-acting beta2-agonists plus (if needed) oral corticosteroids.	Preferred treatment: High-dose inhaled corticosteroids combined with long-acting inhaled beta2-agonists. Add, if needed: Oral corticosteroids. Repeat attempts should be made to reduce use of systemic corticosteroid and maintain control with inhaled corticosteroid.
Adapted from National Asthma Education and Prevention Program (NAEPP) Expert Panel Report: Guidelines for the Diagnosis and Management of Asthma – Update on Selected Topics 2002 (EPR-2 Update).

Most asthma drugs are inhaled using various forms of inhalers or nebulizers. Inhaled drugs must be used regularly as prescribed and the patient carefully trained in their use in order for them to be effective and safe. Studies suggest that many children fail to use the devices properly, although newer devices are easier to use than others. The basic devices are the metered-dose inhaler (MDI), breath-actuated inhalers, dry powder inhalers, and nebulizers.

MDIs have used chlorofluorocarbons (CFCs) as their propellants. CFCs are damaging to the environment and are now being replaced with other propellants (hydrofluoroalkane) that are more environmentally safe, and do not chill the device as CFCs do. Devices that don't use any propellants are also now available.

Metered-Dose Inhaler. The standard device for administering any asthma medication is the metered-dose inhaler (MDI). This device, particularly when used with a spacer, allows precise doses to be delivered directly to the lungs. (The spacer is a tube that is attached to the inhaler. It serves as a holding chamber for the medication that is sprayed by the inhaler.) MDI-delivered drugs must be used regularly as prescribed and the patient carefully trained in their use in order for them to be effective and safe. Some patients hold the MDI too close to their mouths, or even inside them. Others may exhale too forcefully before inhalation.

The spacer helps improve medication delivery by allowing the patient additional time to inhale. They vary, however, in their effectiveness. It should be noted that MDIs can continue to deliver propellant even after the drug has been used up. Patients should track their medicine and throw the device away when the last dose has been administered.

Nebulizers (not MDIs) are typically used in very small children, both at home and in the emergency room. However, recent studies suggest spacers may be better than nebulizers for children and shorten the time spent in emergency rooms. Studies also indicate that with the use of a face mask and a spacer, the MDI works well even for infants in the emergency room and may prove to be useable at home.

Click the icon to see an illustrated series detailing a metered dose inhaler.

Breath-Actuated Inhalers. Breath-actuated rotary inhalers (Easi-Breathe and Autohaler) deliver the drug directly to the back of the throat as the user inhales. Their primary advantage over the MDI is their ease of use. They also do not use CFCs as propellants. In comparison studies, patients have been very successful with the breath-actuated inhalers. They are not recommended for children under 8 years old.

Dry Powder Inhalers. Dry powder inhalers (DPIs) deliver a powdered form of beta2-agonists or corticosteroids directly into the lungs. Such devices include Rotahaler, Spinhaler, Turbohaler, Clickhaler, Easyhaler, Diskhaler, Discus, Twisthaler, Spiros, and others. DPIs are as effective as the older devices, and generally have a better taste and are easier to manage. They may differ among themselves, however, in their ability to deliver drugs into the airways. In one study, for example, the Turbohaler was easier to use than the Diskhaler and so achieved better delivery.

Humidity or extreme temperatures can affect DPIs' performance, so they should not be stored in humid places (bathroom cabinets) or locations subject to high temperatures (glove compartments during summer months).

Dry-powder may cause tooth erosion. Children are advised to rinse their mouths out right after using these inhalers and to brush twice a day with a fluoride toothpaste.

Other Hand-Held Inhalers. Respimat delivers a fine-mist spray that is created by forcing the liquid medication through nozzles. It does not use any propellant.

Nebulizers. A nebulizer is a machine that delivers a fine spray of medication-containing liquid. Nebulizers are often used for children younger than 3 years and sometimes for older children who have difficulty using the MDI. It takes 5 - 10 minutes to administer medication using a nebulizer. Because the spray is less targeted than with the inhaler, it must deliver large amounts of the drug. This increases the risk for toxicity and severe side effects. Nebulizers should not be used by children who can manage an inhaler. Their use has been associated with a higher rate of hospitalizations and longer duration of symptoms than inhalers. A 2007 study also suggested that the misuse of home nebulizers may be an important factor in asthma deaths in children and young adults. If children must use an albuterol nebulizer, parents should be sure that it does not contain the preservative benzalkonium, which actually narrows the airways.

Click the icon to see an illustrated series detailing the use of a nebulizer.

Asthma triggers a vicious emotional-physical cycle:

Breathlessness and wheezing incite a fear of suffocation and death, even in very small children.
This anxiety produces further constriction on the muscles surrounding the airways, which makes breathing even more difficult.

Caregivers must first focus on alleviating their own anxiety, which can heighten a child's own fears. The next step is to help the child relax. One method for this is as follows:

The child sits comfortably, bending slight forward with the eyes closed.
The hands are placed gently over the navel.
The child is then told to pretend the stomach is a balloon.
The "balloon" must be "blown up" by inhalation, not exhalation. The child can tell if this working because the hands will move slightly apart.
When the child breathes out, the "balloon" will be made flat.

This exercise both relaxes the child and discourages shallow, oxygen-poor breathing. Massaging the child in gentle circles on the chest is relaxing and may also loosen mucus.

Other recommendations include:

A child may also find relief by lying stomach-down on several pillows so that the head is slightly lower than the chest while the caregiver gently pats the back between the shoulder blades.
Warm liquids, such as soup or hot cider, are effective in loosening mucus and may also relax bronchial muscles. Cold fluids, like cold air, should be avoided.
Overhydration (too much liquid) can be harmful, however, so these drinks should not be forced on the child.
Warm, moist air from vaporizers can greatly ease and moderate asthma attacks.
Daily massages and breathing and relaxation techniques to reduce stress can be very helpful.

Many adults self-manage their asthma using daily monitoring of peak air flow with adjustments of the medications as needed. This involves the use of a peak flow meter, which measures peak expiratory flow rate (PEFR).

Click the icon to see an image of a peak flow meter.

Studies suggest, however, that for most children with asthma, an educational program is just as effective for managing the condition as monitoring. Most children do not need to monitor their peak air flow on any regular basis.

Quick-Relief Medications

These medications quickly control acute asthma attacks.

Beta2-agonists do not reduce inflammation or airway responsiveness but serve as bronchodilators, relaxing and opening constricted airways during an acute asthma attack. A short-acting inhaled beta2-agonist, taken as needed, is often the only medication used by children with chronic mild asthma.

Asthma is a disease in which inflammation of the airways causes airflow into and out of the lungs to be restricted. When an asthma attack occurs, mucus production is increased, muscles of the bronchial tree become tight, and the lining of the air passages swells, reducing airflow and producing the characteristic wheezing sound.

Specific short-acting beta2-agonists include:

Albuterol (Proventil, Ventolin), called salbutamol outside the U.S., is the standard short-acting beta2-agonist in America. Other similar beta2-agonists are isoproterenol (Isuprel, Norisodrine, Medihaler-Iso), metaproterenol (Alupent, Metaprel), pirbuterol (Maxair), terbutaline (Brethine, Brethaire, Bricanyl), and bitolterol (Tornalate). Isoetharine (Bronkometer, Bronkosol) is available in nebulizers.
Newer beta2-agonists, including levalbuterol (Xopenex), have more specific actions than the standard drugs. Xopenex is administered with a nebulizer, and studies have indicated that it is as effective as albuterol with fewer side effects. The original formulation of Xopenex was administered with a nebulizer. A new metered-dose inhaler formulation was launched at the end of 2005. It is approved for children age 4 years and older.

Short-acting bronchodilators are generally administered through inhalation and are effective for 3 - 6 hours. They relieve the symptoms of acute attacks, but they do not control the underlying inflammation. If asthma continues to worsen with the use of these drugs, a doctor may prescribe corticosteroids or other drugs to treat underlying inflammation.

Side Effects of Beta2-Agonists. Side effects of all beta2-agonists may include:

Anxiety
Tremor
Restlessness
Headache
Fast and irregular heartbeats. A doctor should be notified immediately if this side effect occurs.
These drugs should be taken with caution by children with diabetes or a history of seizures.
Beta2-agonists have serious interactions with certain drugs and parents should tell the doctor about any other medications their child is taking.

Loss of Effectiveness and Overdose. There has been some concern that short-acting beta2-agonists become less effective when taken regularly over time, increasing the risk for overuse. Over time, some patients may become tolerant to many effects of short-acting beta2-agonists. The degree to which this affects the airways is uncertain. In some studies, the duration of action has declined but the peak effect appears to be preserved, making these drugs still useful for acute attacks. Regular use of long-acting beta2-agonists may increase the chances of a reduced effect from the short-acting forms.

A 2005 landmark study suggested that patients’ differing clinical response to albuterol may be based on their genotype. Albuterol targets the beta-adrenergic receptor. In the Beta-Adrenergic Response by Genotype (BARGE) trial, researchers studied the effects of albuterol on patients with two different forms of this receptor. The results suggested that patients with the arginine form of the receptor did not respond to albuterol. These patients’ asthma symptoms actually improved when albuterol was not used. By contrast, patients with the glycine form of the receptor had improved asthma control with albuterol.

Inhaled ipratropium bromide (Atrovent) acts as a bronchodilator over time. Ipratropium bromide alone is only modestly beneficial for acute asthma attacks. In fact, the drug is not approved specifically for asthma. Some parents report benefit for treating wheezing in infants. It is also sometimes used in the emergency room to treat children with severe asthma to enhance the effects of intravenous beta2-agonists.

Common oral corticosteroids include prednisone/prednisolone, dexamethasone, methylprednisolone, and hydrocortisone. They reduce inflammation very effectively. A 2006 study indicated that oral prednisolone worked better than inhaled fluticasone for treating mild-to-moderate asthma attacks in children in emergency rooms. However, children often have difficulty taking these drugs because they have a bitter taste and can cause vomiting. Taking oral dexamethasone for 2 days may be as effective and more tolerable than the standard 5-day regimen of prednisone/prednisolone. Prolonged use of oral steroids has widespread and sometimes serious side effects, so they are not generally give to children for longer than a few days.

[See In-Depth Report #4: Asthma in adults.]

Long-Term Relief Medications

These medications are taken on a regular basis to prevent asthma attacks and control chronic symptoms.

Corticosteroids, also called glucocorticoids or steroids, are powerful anti-inflammatory drugs. Steroids are not bronchodilators (they do not relax the airways) and have little effect on symptoms. Instead, they work over time to reduce inflammation and prevent permanent injury in the lungs. They can also help prevent asthma attacks from occurring. Many studies have shown that the use of inhaled corticosteroids in patients with moderate-to-severe asthma significantly reduces the rate of rehospitalizations and deaths from asthma.

Inhalation of corticosteroids makes it possible to provide effective local anti-inflammatory activity in the lungs with minimal systemic effects. (By contrast, oral steroids have considerable side effects throughout the body.) Inhaled corticosteroids are recommended as the primary therapy under the following circumstances:

For any asthmatic condition more serious than occasional episodes of mild asthma. (Low-doses of inhaled steroids may even be safe and effective for some people with mild asthma, particularly those who find themselves using beta2-agonists daily.)
When treatment with bronchodilators is not effective.

Examples of inhaled corticosteroids:

Inhaled steroids include fluticasone (Flovent), budesonide (Pulmicort), triamcinolone (Azmacort and others), and flunisolide (AeroBid). In general, the newer drugs are more powerful than the older generation of inhaled drugs. Budesonide (Pulmicort Respules) is available in a jet nebulizer for children from 12 months to 8 years. It is the first such medication to be approved for children in this age group.
The FDA approved a new inhaled corticosteroid, mometasone furoate (Asmanex) was approved in 2005 for patients age 12 and older.
The older corticosteroid inhalants are beclomethasone (Beclovent, Vanceril) and dexamethasone (Decadron Phosphate Respihaler and others). They are less powerful than the newer steroids when delivered with standard inhalers. New inhalers that use very fine sprays (QVAR, Autohaler) to deliver the drugs deep into the lungs may prove to be as effective as the newer, more potent steroids.
Inhalers that combine both long-acting beta2-agonists and corticosteroids are also available. These include Symbicort (budesonide/formoterol), which was approved in 2006 for patients ages 12 years and older.

Expert guidelines recommend inhaled corticosteroids as the preferred first-line therapy for children with mild-to-moderate asthma. Nevertheless, they are still significantly underprescribed in the patients who need them most. An important 2007 study of 6 - 14 year old children with asthma compared inhaled corticosteroid therapy (fluticasone) with an inhaled corticosteroid/long-term beta2 agonist (fluticasone/salmeterol) and a leukotrine receptor antagonist (montelukast). The results indicated that fluticasone alone worked better than the other two treatments.

Researchers have been investigating whether early treatment with corticosteroids can help prevent the development of asthma in at-risk children. Two important 2006 studies in the New England Journal of Medicine suggested that while inhaled corticosteroids helped ease symptoms and reduce breathing problems in pre-school children at risk for asthma, they did not help protect against asthma development.

For now, experts caution against corticosteroids for infants and toddlers with mild asthma and urge close monitoring especially for children under age 5 with severe asthma who are receiving high doses. Because the newer potent drugs, particularly fluticasone, may produce major side effects similar to oral steroids, it is important when treating all children to aim for the lowest effective dose possible. Fortunately, studies suggest that low doses of fluticasone may achieve the same benefits as with high ones, thus reducing risks for serious side effects. Better delivery methods may also allow lower doses.

Side effects of inhaled steroids may include:

The most common side effects are throat irritation, hoarseness, and dry mouth. These effects can be minimized or prevented by using a spacer device and rinsing the mouth after each treatment.
Rashes, wheezing, facial swelling (edema), fungal infections (thrush) in the mouth and throat, and bruising are also possible but not common with inhalators.
Some children experience changes in mood, memory, and behavior. These changes are not permanent.
Some studies have suggested a higher risk for gum inflammation.
Oral steroids reduce bone density. Research reports that inhaled steroids -- both older and newer drugs -- may also affect bone growth and density. However, a number of studies report only a slight effect (about half an inch) on children's growth, which may be only temporary. It is still unknown if these drugs have any significant long-term effect on bone density. Calcium supplements may help prevent bone loss that is due to inhaled steroids.
It is not yet known whether inhaled steroids affect lung growth in very young children. Steroids administered using nebulizers are of particular concern.
There is also some concern that the stronger drugs, particularly fluticasone, suppress the adrenal system to a greater degree than other steroid inhalants. This effect, in turn, reduces levels of natural steroids -- notably cortisol, the major stress hormone. (This is a serious side effect of oral steroids).

Long-acting beta2-agonists are used in combination with inhaled corticosteroids for treating children with moderate-to-severe asthma. These drugs include include salmeterol (Serevent Diskus) and formoterol (Foradil Aerolizer). A single inhaler (Advair Diskus) that combines both salmeterol and the corticosteroid fluticasone is available for children age 4 years and older, and an inhaler (Symbicort) combining formoterol and the corticosteroid budesonide is approved for children age 12 years and older.

Long-acting beta2-agonists are used for preventing an asthma attack (not for treating attack symptoms). The effects of one dose of a long-acting beta2-agonist last for about 12 hours, so they are particularly effective during the night. These drugs also may be used for prevention of exercise-induced asthma in people and to protect against aspirin-induced asthma.

However, research indicates that long-acting beta2-agonists can worsen asthma by increasing symptom severity. These drugs may also increase the risk for asthma-related deaths. Experts are still trying to determine when long-acting beta2-agonists should be added to an asthma treatment plan. If a child’s symptoms do not improve or if symptoms worsen with this type of drug, the doctor will recommend discontinuing it. Patients should not, however, stop taking this drug or other asthma medications without first talking with their doctors.

Side Effects. Side effects of long-acting beta2-agonists are similar to the short-acting drugs.

Specific Warning on Salmeterol and Formoterol. In 2003 a "black box" warning was added to product packaging for drugs that contain salmeterol, including Serevent Diskus, and Advair Diskus. Serevent and Advair are approved for patients age 12 years and older. The warning was based on a study that demonstrated more serious and even fatal asthma episodes in patients who used the drug than in patients who used a placebo.

In 2006, the FDA updated the warning to include formoterol (Foradil Aerolizer, approved for patients 5 years and older). Warnings for salmeterol and formoterol products emphasize that these medicines can increase the risk of severe asthma episodes. Long-acting beta2-agonists require up to 20 minutes to achieve effectiveness, and there is a danger of overdose if a patient is not aware of this delay and takes additional doses to achieve faster relief. The FDA recommends that patients:

Use long-acting beta2-agonists only if other medicines (such as steroids) have not helped control asthma.
Use a short-acting bronchodilator, not a long-acting beta2-agonist, to treat sudden wheezing.
Do not use long-acting beta2-agonists to treat wheezing that is getting worse. Call your doctor if this situation occurs.
Do not stop using any asthma medicines without first talking to your doctor.

Cromolyn sodium (Intal) is both an anti-inflammatory drug and has antihistamine properties that block asthma triggers such as allergens, cold, or exercise. Cromolyn has been the anti-inflammatory drug of choice for prevention of asthma attacks in children over age 4 with chronic moderate asthma. It is not as effective as inhaled corticosteroids, however, for reducing hospitalization rates, improving symptoms, and reducing the use of beta2-agonists in children with persistent asthma. Still, cromolyn has a well-known long-term safety record, while the long-term adverse effects of corticosteroids in children are still not fully known. Many children who need asthma maintenance therapy will still do well on cromolyn. (It may not provide any real benefit for children under age 4.)

Nedocromil (Tilade) is similar to cromolyn and needs to be taken only once a day. It also prevents asthmatic reactions to cold and exercise. It is not used in very young children. A cromolyn nasal spray called Nasalcrom has been approved for over-the-counter purchase, but only to relieve nasal congestion caused by allergies. Patients should not use it for self-medication without the advice of a doctor.

Side Effects. Side effects of cromolyn include nasal congestion, coughing, sneezing, wheezing, nausea, nosebleeds, and dry throat. Nedocromil has an unpleasant taste, and some people have complained of nausea, headache, and spasms in the airways, but no serious side effects have been reported.

Leukotriene-antagonists (also called anti-leukotrienes or leukotriene modifiers) are oral medications that block leukotrienes. Leukotrienes are powerful immune system factors that, in excess, produce a battery of damaging chemicals that can cause inflammation and spasms in the airways of people with asthma. As with other anti-inflammatory drugs, leukotrienes are used for prevention and not for treating acute asthma attacks.

Leukotriene-antagonists include zafirlukast (Accolate), montelukast (Singulair), zileuton (Ziflo), and pranlukast (Ultair, Onon). These drugs are proving helpful for long-term prevention of asthma, including exercise-induced asthma and aspirin (or NSAID) -induced asthma. However, most studies to date have reported better success with inhaled corticosteroids than with the leukotriene-antagonists. A 2006 study of children with mild-to-moderate persistent asthma indicated that the corticosteroid fluticasone worked better than the leukotriene-antagonist montelukast in controlling symptoms. Nevertheless, some studies suggest that montelukast, which comes in a chewable tablet, may be particularly useful for managing asthma in small children (ages 2 - 5), since they have trouble with inhaled steroids.

Side Effects and Complications. Gastrointestinal distress is the most common side effect of leukotriene-antagonists. Very few other side effects have been reported. In general, these drugs appear to be safe and well-tolerated.

Of some concern are reports of Churg-Strauss syndrome in a few people taking zafirlukast or montelukast. Churg-Strauss syndrome is very rare, but it causes blood vessel inflammation in the lungs and can be life threatening. Oral steroids quickly resolve the problem. In fact, usually the syndrome has occurred in patients who were tapering off steroids and changing over to the leukotriene-antagonists. Some experts believe that, in such cases, the steroids may simply have masked the presence of the disorder, which then developed when the steroid drugs were withdrawn. Symptoms include severe sinusitis, flu-like symptoms, rash, and numbness in the hands and feet.

Other concerns are indications of liver injury in patients taking zileuton and zafirlukast when taken at higher than standard doses. No adverse effects on the liver have been reported to date with montelukast.

Theophylline (Theo-Dur, Theolair, Slo-Phyllin, Slo-bid, Constant-T, Respbid) is a mild-to-moderate bronchodilator that has been used to treat childhood asthma for more than 30 years. It is useful for treating nocturnal asthma and may also have anti-inflammatory qualities even in low doses.

Available in tablet, liquid, and injectable forms, some theophylline sustained-release tablets and capsules have a long duration of action and can therefore be taken once or twice a day with good results.

Side effects may include changes in behavior, mood, and memory. If theophylline is not taken exactly as prescribed, an overdose can easily occur. Toxicity can cause nausea, vomiting, headache, insomnia, and, in rare cases, disturbances in heart rhythm and convulsions. Contact a doctor immediately if any of these side effects occur.

The risks for these adverse effects are small if the drug is taken exactly as prescribed but the following precautions should be noted:

Infants tend to metabolize the drug extremely slowly and, therefore, should receive very low doses.
By the time children reach age 1, however, they metabolize the drug faster than adults. There is a risk, therefore, of toxic effects.
Fever and certain antibiotics may slow down the rate at which theophylline is eliminated from the body. In such cases, the doctor may want to reduce the dosage of theophylline.

If a child is taking theophylline on an ongoing basis, the doctor should monitor the drug level at the start of therapy and at regular intervals thereafter.

Omalizumab (Xolair) is FDA-approved for patients age 12 and older who have moderate-to-severe persistent asthma related to allergies. The first drug of this type to be approved for asthma, omalizumab is a monoclonal antibody (MAb), a genetically developed drug designed to attack very specific targets. Omalizumab is administered by injection every 2 - 4 weeks. It is used only to treat patients whose symptoms are not controlled by inhaled corticosteroids.

Omalizumab prevents the antibody immunoglobulin E (IgE) from triggering the inflammatory events that lead to asthmatic attacks. Studies have shown excellent benefits of the drug, including a reduced need for corticosteroids, fewer hospitalizations, and significant symptomatic improvements.

However, about 1 in 1,000 patients who take omalizumab develop anaphylaxis (a life-threatening allergic reaction). In 2007 the FDA requested the manufacturers of omalizumab to put a “boxed warning” on the medicine’s label emphasizing the drug’s risk for anaphylaxis. The boxed warning notes that patients can develop anaphylaxis after any dose of omalizumab, even if they had no reaction to a first dose. Anaphylaxis may occur up to 24 hours after the dose is given.

The FDA recommends that healthcare providers observe patients for at least 2 hours after an injection. Patients should also carry emergency self-treatment for anaphylaxis (such as an Epi-Pen) and know how to administer it. With an Epi-Pen, or similar auto-injector device, patients can quickly give themselves a life-saving dose of epinephrine.

Anaphylaxis symptoms include:

Difficulty breathing
Chest tightness
Dizziness
Fainting
Itching and hives
Swelling of the mouth and throat

[See In-Depth Report #4: Asthma in adults.]

Other Treatments

Alternative therapies are widely used by children, adolescents, and adults with asthma. In one study, nearly half of asthma or allergy sufferers resorted to alternative treatments. To date, however, evidence does not support most alternative therapies, including high-dose vitamins, urine injections, homeopathic remedies, and most herbal remedies.

Relaxation and Stress-Reduction Techniques. Patients report benefits from many stress reduction and physical techniques, such as acupuncture, hypnosis, breathing relaxation techniques, the Alexander technique, massage therapy, and meditation practices. There have been very few well-conducted studies supporting their use, however.

Acupuncture, hypnosis, and biofeedback are alternative ways to control pain. Acupuncture involves the insertion of tiny sterile needles, slightly thicker than a human hair, at specific points on the body.

Breathing Exercises. Some studies have suggested that breathing exercises or training may be helpful. A number of different methods are available. One example is the Buteyko breathing method, an experimental approach designed to increase levels of carbon dioxide in the body. To do this, patients are trained to reduce their volume of breath and to avoid hyperventilation (over-breathing). Some studies report that patients using this method reduce their use of medications and improve their quality of life. The system originated in Australia and is not yet widely available in the U.S.

Probiotics. Probiotics are beneficial bacteria that may possibly help protect against allergies and asthma. Antibiotic overuse and modern hygiene may specifically be reducing these helpful organisms. Look for probiotics in active yogurt cultures and in supplements, which are being studied for protection.

Herbal Remedies. Butterbur (also known as Petasites hybridus, butter dock, blatterdock, bog rhubarb, and exwort), is a traditional herbal remedy used for seasonal allergies and asthma. In a 2002 study, it was as effective and less sedating than a commonly prescribed antihistamine for treating seasonal allergies over a 2-week period. However, little research exists on its effect on asthma. Overall, there is scant evidence supporting the benefits of herbs and nutritional supplements for asthma control.

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 a number of 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.

Managing Asthma

The more allergies a child has, the more severe the asthma. Making lifestyle changes to reduce allergy attacks and other triggers is extremely important.

House dust is a reservoir for pollen and dust mites. Some experts believe that reducing household allergens and pollutants in the home could reduce asthma in children by 40%.

Controlling for Dust. Spray furniture polish is very effective for reducing both dust and allergens. Air cleaners, filters for air conditioners, and vacuum cleaners with High Efficiency Particular Air (HEPA) filters can help remove particles and small allergens found indoors. Neither vacuuming nor the use of anti-mite carpet shampoo, however, is effective in removing mites in house dust. Vacuuming actually stirs up both mites and cat allergens. If possible, avoid carpets and rugs.

Click the icon to see an image of a HEPA air filter.

Bedding and Curtains. Many experts recommend reducing exposure to dust mites by enclosing mattresses and pillows in semipermeable coverings. (Vinyl mattress covers limit airflow and may also worsen, or even cause, asthma in children. Synthetic pillows may pose a significantly higher risk for severe asthma attacks in children than feather or no pillows.) However, several 2005 studies suggested that such covers do not prevent asthma or allergies. Replace curtains with shades or blinds, and wash bedding using the highest temperature setting.

Click the icon to see an image of dust mite prevention.

One study found that children sleeping in bottom bunk beds are significantly more likely to develop asthma than siblings occupying the upper bunks. Families with children who have asthma or allergies should avoid bunk beds or be sure that children with asthma sleep in the top bunk. Even with standard beds, it may be useful to have them sleep as high off the floor as possible.

Exterminating Pests (Cockroaches and Mice). Use professional exterminators to eliminate cockroaches. (One study reported that ridding a home of cockroaches and cleaning the house using standard housecleaning techniques failed to eliminate the cockroach allergens themselves.) Exterminate mice, and attempt to remove all dust, which might contain mouse urine and dander.

Reducing Humidity in the House. Although warm, moist air from vaporizers can greatly ease and moderate asthma attacks, living in a damp house is counterproductive. Dust mites thrive in humidity and damp houses increase the risk for mold, so on-going humidifiers can be unhelpful. If they are used, humidity levels should not exceed 40%, and humidifier should be cleaned daily with a vinegar solution.

Controlling Pets. People with asthma who already have pets and are not allergic to them probably have a low risk for developing such allergies later on. When children are exposed to more than one dog or cat during their first year, they have a much lower risk for allergies and asthma.

For children who have an existing allergy to pets, however, the pets should be given away or kept outside. If this isn't possible, they should at least be confined to carpet-free areas outside the bedroom. Cats harbor significant allergens, which can even be carried on clothing; dogs usually present fewer problems. Washing animals once a week can reduce allergens. Dry shampoos, such as Allerpet, are now available for both cats and dogs to remove allergens from skin and fur and are easier to administer than wet shampoos.

Many of the same substances trigger both allergies and asthma. Common allergens include pollen, dust mites, mold and pet dander. Other asthma triggers include irritants like smoke, pollution, fumes, cleaning chemicals, and sprays. Asthma symptoms can be substantially reduced by avoiding exposure to known allergens and respiratory irritants.

Preventing Exposure to Cigarette and Cooking Smoke. Parents who smoke are strongly urged to quit. Studies indicate that exposure to second-hand smoke in the home increases the risk for asthma and asthma-related emergency room visits in children. Even smoky cooking can worsen asthma.

Parental smoking has been shown to increase the airway responsiveness of infants as early as the first 2 - 10 weeks of life. This extends even to the fetus of pregnant women who smoke. Such mothers tend to have babies born at a low birth weight, which affects lung function and increases babies' risks for asthma.

Avoiding Outdoor Allergens. The following are some recommendations for avoiding allergens outside:

Avoid scheduling camping and hiking trips during times of high pollen count (generally, May and June for grass pollen and mid-August to October for ragweed).
Patients should avoid strenuous activity when ozone levels are highest, which usually occur in early afternoon, particularly on hot hazy summer days. Levels are lowest in early morning and at dusk.
Asthma attacks are often higher during thunderstorms. Some evidence points to a build-up of ozone that accompanies such storms. Other evidence suggests that the changing airflow patterns bring a sudden downdraft of air containing concentrations of pollens, small particles and allergens.
Patients who are allergic to mold should avoid barns, hay, raking leaves, and mowing grass.
Exposure to automobile fumes may worsen asthma. Fungi in car air conditioners can also be a problem.

Reducing Exposure to Air Pollution. Children breathe faster than adults, taking in more pollutants, and therefore are particularly susceptible to soot and other small particles in the air. A 2001 study found an association between higher rates of asthma and other health problems in children who were exposed to high levels of specific pollutants (particularly sulfur dioxide and nitrogen dioxide). Diesel fuel exhaust has also been associated with worsening asthma in children.

Some experts point out that asthma rates in North America have increased over recent years while the prevalence of many common air pollutants have declined. So pollution is unlikely to be a primary cause of asthma. Regardless of whether pollution is an important cause of asthma, evidence strongly suggests that it can affect existing asthma.

Patients with asthma and chronic allergic rhinitis may require daily medications. Patients with severe seasonal allergies may be advised to start medications a few weeks before the pollen season, and to continue it until the season is over.

Immunotherapy ("allergy shots") may help reduce asthma symptoms, and the use of asthma medications, in patients with known allergies. They may also help prevent the development of asthma in children with allergies. Immunotherapy poses some risk for severe allergic reactions, especially for children with poorly controlled asthma, so it is important that the doctor carefully evaluates the child’s asthma condition.

[See In-Depth Report #77: Allergic rhinitis.]

Weight Loss. Children who are both asthmatic and overweight may reduce asthma symptoms simply with weight loss.

Fruits, Vegetables, and Whole Grains. Healthy foods are important for lung function. Specific foods that may be important for healthy lungs contain antioxidants (deep green and yellow-orange fruits and vegetables), selenium (fish, red meat, grains, eggs, chicken, liver, garlic), plant chemicals called flavonoids (apples, onions), and magnesium (green leafy vegetables, nuts, whole grains, milk, and meats).

Fish Oil. Omega-3 fatty acids, found in cold water oily fish and in supplements (preferably DHA-EPA, the important compounds in fish oil) have anti-inflammatory effects. Some evidence suggests they may be helpful for people with asthma.

Caffeine. Caffeine has properties that are similar to the asthma drug theophylline. A major analysis of studies reported that caffeine improved lung function for up to 4 hours after consumption. Although tea and coffee are the major sources of caffeine, some sodas contain it and should be avoided when children have an asthma attack. (People who are going to have their lung function tested should avoid drinking coffee, tea, or other caffeinated beverages for at least 4 hours beforehand.)

Food Allergies. Although about 70% of people with asthma believe their symptoms are aggravated by food allergies, studies indicate that this belief may be true in only 5% of cases. If young children show signs of or test positive for food allergies, however, parents should be extra cautious in preventing exposure to any asthma trigger. Some doctors now counsel all children with asthma to avoid nuts entirely, and, of course, children who experience reactions to any foods should avoid them.

Chemicals that may pose some risk for an allergic reaction are monosodium glutamate, or MSG (found in some canned soups, cheese, and certain vegetables), and sulfites (preservatives in foods, such as frozen potatoes and tuna). Contrary to what many believe, dairy products do not appear to worsen asthma symptoms in people who are not already allergic to them.

Asthma is no reason to avoid exercise. Historically, about 10% of Olympic athletes have asthma. Some studies indicate that long-term exercise may help control asthma and reduce hospitalization.

Encourage children with asthma to swim and play sports, such as baseball, that will present less difficulty for them. Intense activities lasting less than 2 minutes, such as sprinting or competitive swimming, may cause fewer problems than longer-lasting exercises.

Young people who enjoy running should probably choose an indoor track to avoid pollutants. Swimming is excellent for people with asthma. Yoga practice, which uses both stretching, breathing, and meditation techniques, may have particular benefits. One study reported that two-thirds of patients who practiced yoga regularly were able to reduce or stop taking their asthma medications.

Patients should consult their doctors before starting any exercise program. Exercise-induced asthma is a limited condition that has specific recommendations.

People with asthma should try to minimize their risk for respiratory tract infections. Washing hands is a very simple but effective preventive measure.

Patients with asthma should ask their doctor about getting the influenza ("flu") vaccine and also whether they should receive the vaccination against pneumococcal pneumonia.

Zanamivir, a new drug used for treating influenza, is considered safe for patients with asthma 12 years of age or older. In one study, patients with asthma treated with zanamivir experienced fewer flu symptoms, and their lung function improved.

People with asthma have no higher rate of anxiety or depression than the general population. However, such emotions interact with the effects of asthma and its treatments in important ways:

Negative emotions can discourage compliance with medication and the ability to cope.
Poor control of asthma symptoms, in turn, increases the risk for negative emotions.
Stress and depression have been associated with more severe symptoms and even an increased risk of fatal asthma attacks.

Some evidence suggests that stress reduction techniques, a positive attitude, and relaxation techniques may be very helpful in the long-term management of asthma.

Resources

www.lungusa.org -- The American Lung Association
www.acaai.org -- American College of Allergy, Asthma & Immunology
www.aaaai.org -- American Academy of Allergy, Asthma, and Immunology
www.nhlbi.nih.gov -- National Heart, Lung, and Blood Institute
www.asthma-carenet.org -- Childhood Asthma Research and Education Network
www.njc.org -- National Jewish Center for Immunology and Respiratory Medicine
www.aafa.org -- Asthma and Allergy Foundation of America
www.aanma.org -- Allergy and Asthma Network, Mothers of Asthmatics

References

Akinbami L; Centers for Disease Control and Prevention National Center forHealth Statistics. The state of childhood asthma, United States, 1980-2005. Adv Data. 2006 Dec 12;(381):1-24.

Bisgaard H, Hermansen MN, Loland L, Halkjaer LB, Buchvald F. Intermittent inhaled corticosteroids in infants with episodic wheezing. N Engl J Med. 2006 May 11;354(19):1998-2005.

Cates CJ, Crilly JA, Rowe BH. Holding chambers (spacers) versus nebulisers for beta-agonist treatment of acute asthma. Cochrane Database Syst Rev. 2006 Apr 19;(2):CD000052.

Douwes J, van Strien R, Doekes G, Smit J, Kerkhof M, Gerritsen J, et al. Does early indoor microbial exposure reduce the risk of asthma? The Prevention and Incidence of Asthma and Mite Allergy birth cohort study. J Allergy Clin Immunol. 2006 May;117(5):1067-73.

Guilbert TW, Morgan WJ, Zeiger RS, Mauger DT, Boehmer SJ, Szefler SJ, et al. Long-term inhaled corticosteroids in preschool children at high risk for asthma. N Engl J Med. 2006 May 11;354(19):1985-97.

Haland G, Carlsen KC, Sandvik L, Devulapalli CS, Munthe-Kaas MC, Pettersen M, et al. Reduced lung function at birth and the risk of asthma at 10 years of age. N Engl J Med. 2006 Oct 19;355(16):1682-9.

Marks GB, Mihrshahi S, Kemp AS, Tovey ER, Webb K, Almqvist C, et al. Prevention of asthma during the first 5 years of life: a randomized controlled trial. J Allergy Clin Immunol. 2006 Jul;118(1):53-61.

National Asthma Education and Prevention Program Expert Panel Report: Guidelines for the Diagnosis and Management of Asthma Update on Selected Topics -- 2002. Rockville, MD. National Heart, Lung, and Blood Institute, US Dept of Health and Human Services; 2003. NIH publications 02-5074.

O'Byrne PM, Pedersen S, Busse WW, Tan WC, Chen YZ, Ohlsson SV, et al. Effects of early intervention with inhaled budesonide on lung function in newly diagnosed asthma. Chest. 2006 Jun;129(6):1478-85.

Salpeter SR, Buckley NS, Ormiston TM, Salpeter EE. Meta-analysis: effect of long-acting beta-agonists on severe asthma exacerbations and asthma-related deaths. Ann Intern Med. 2006 Jun 20;144(12):904-12.

Schuh S, Dick PT, Stephens D, Hartley M, Khaikin S, Rodrigues L, Coates AL. High-dose inhaled fluticasone does not replace oral prednisolone in children with mild to moderate acute asthma. Pediatrics. 2006 Aug;118(2):644-50.

Sorkness CA, Lemanske RF Jr, Mauger DT, Boehmer SJ, Chinchilli VM, Martinez FD, et al. Long-term comparison of 3 controller regimens for mild-moderate persistent childhood asthma: the Pediatric Asthma Controller Trial. J Allergy Clin Immunol. 2007 Jan;119(1):64-72.

Review Date:
3/26/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Allergic rhinitis

FitSugar — Wed, 08 Oct 2008 17:34:54 -0700

Overview

Signs and Symptoms
Causes
Risk Factors
Diagnosis
Prevention
Treatment
Other Considerations
Supporting Research

HEALTH GUIDE REFERENCE FROM A.D.A.M

Allergic rhinitis is an allergic reaction that occurs when your immune system overreacts to substances that you have inhaled (often pollen). The two types of allergic rhinitis are seasonal allergic rhinitis (hay fever) and perennial allergic rhinitis, which occurs year-round. Hay fever is caused by outdoor allergens, and perennial allergic rhinitis by indoor allergens (such as dust mites, pet dander, mold).

Symptoms of allergic rhinitis resemble a cold, but they are not caused by a virus. When you inhale an allergen, your immune system springs into action, releasing substances known as IgEs into your nasal passages, along with inflammatory chemicals such as histamines. Your nose, sinuses, or eyes may become itchy and congested. Scientists aren't sure what causes your immune system to overreact to an allergen.

Allergic rhinitis is a common condition, affecting about 1 in 5 Americans. Symptoms can be mild or severe. Many people who have allergic rhinitis also have asthma.

Signs and Symptoms

Allergic rhinitis can cause many symptoms, including the following:

Stuffy, runny nose
Sneezing
Post-nasal drip
Red, itchy, and watery eyes
Swollen eyelids
Itchy mouth, throat, ears, and face
Sore throat
Dry cough
Headaches, facial pain or pressure
Partial loss of hearing, smell, and taste
Fatigue
Dark circles under the eyes

Causes

The body's immune system is designed to fight harmful substances like bacteria and viruses. But in allergic rhinitis, the immune system overresponds to harmless substances -- like pollen, mold, and pet dander -- and launches an assault. This attack is called an allergic reaction.

Seasonal allergic rhinitis is caused by an allergic reaction to pollens and spores (depending on the season and area) as they are carried on the wind. Sources include:

Ragweed -- the most common seasonal allergen (fall)
Grass pollen (late spring and summer)
Tree pollen (spring)
Fungus (mold growing on dead leaves, common in summer)

Year-round allergic rhinitis is caused by an allergic reaction to airborne particles from the following:

Pet dander
Dust and household mites
Cockroaches
Molds growing on wall paper, house plants, carpeting, and upholstery

Risk Factors

Family history of allergies
Having other allergies, such as food allergies or eczema
Exposure to secondhand cigarette smoke
Male gender

Diagnosis

Your doctor will ask about your family and personal history of allergy. You may be asked some of the following questions:

Do symptoms vary according to time of day or the season?
Do you have a pet?
Have you made changes to your diet?
Are you taking any medications?

Your doctor will perform a physical exam. Your doctor may also recommend a skin test to determine what you are allergic to. In a scratch test, for example, small amounts of suspected allergens are applied to the skin with a needle prick or scratch. If there is an allergy, a hive (swollen reddened area) forms within about 20 minutes. Sometimes a blood test may be used to determine which allergens you react to.

In young children, observing behavior is helpful in diagnosis. Symptoms of allergic rhinitis may cause a child to wiggle their nose and push the nose upward with the palm of the hand.

Prevention

Taking the following steps to reduce your exposure to allergens may prevent symptoms.

If you have hay fever, during days or seasons when airborne allergens are high:

Stay indoors, and if possible, close the windows.
Use an air conditioner.
Avoid using fans that draw in air from outdoors.
Don't hang laundry outside to dry.
Bathe or shower and change your clothes after being outside.
Use a HEPA air filter in your bedroom.

If you have perennial allergic rhinitis:

Cover your pillows and mattress with dust mite covers.
Remove carpet.
Keep pets out of the bedroom.
Use a HEPA filter on your vacuum.
Use an air purifier.
Avoid pets and other triggers.

Treatment

The best way to reduce symptoms is to avoid or limit your exposure to allergens.

Drugs (such as antihistamines, decongestants, and nasal corticosteroid sprays) may help control symptoms and some complementary, and alternative therapies may also be used to successfully treat the symptoms of allergic rhinitis.

Your doctor may recommend desensitization (immunotherapy, or "allergy shots"). This treatment includes regular injections of the allergen, with each dose being slightly larger than the previous dose. Your immune system should gradually get accustomed to the allergen so that it no longer reacts to it.

In addition, certain lifestyle and dietary changes may help prevent or improve symptoms of allergic rhinitis.

Lifestyle

You can take preventive measures to avoid or reduce your symptoms. Although you can't stay indoors during all high pollen and ragweed seasons, avoiding peak exposure times can help. Run your air conditioner in your home and car, and wear a dust mask when working in the yard.

For perennial allergic rhinitis, you can take the following measures.

To reduce mold:

Clean moldy surfaces. Mold is often found in air conditioners, humidifiers, dehumidifiers, swamp coolers, and refrigerator drip pans.
Use a dehumidifier indoors to reduce humidity to less than 50%.
Fix water leaks and clean up water damage.
Ventilate kitchens, bathrooms, and crawl spaces; vent laundry dryers to the outside.
Put flooring in crawl spaces.
Avoid carpets and upholstered furniture.
Wash bedding every week in hot water.
Keep stuffed toys out of the bedroom.
Cover pillows and beds with allergen-proof covers.

Medications

Depending on the type of allergic rhinitis you have, your doctor may recommend medication. Perennial allergic rhinitis may require daily medication, and if you have seasonal allergic rhinitis (hay fever) you may start medications a few weeks before the pollen season.

Nasal corticosteroids

These prescription sprays reduce inflammation of the nose and help relieve sneezing, itching, and runny nose. They are most effective at reducing symptoms, although you may not see improvement for a few days to a week after you start using them.

Beclomethasone (Beconase)
Fluticasone (Flonase)
Mometasone (Nasonex)
Triacinolone (Nasacort)

Antihistamines

Antihistamines are available in both oral and nasal spray forms, and as prescription drugs and over-the-counter remedies. Over-the-counter antihistamines are short-acting and can relieve mild-to-moderate symptoms. All work by blocking the release of histamine in your body.

Over-the-counter antihistamines -- Include diphenhydramine (Benadryl), chlorpheniramine (Chlor-Trimeton), clemastine (Tavist). These older antihistamines can cause sleepiness. Loratadine (Claritin) does not cause drowsiness.
Prescription antihistamines -- These medications are longer-acting than over-the-counter antihistamines and are usually taken once a day. They include fexofenadine (Allegra) and cetrizine (Zyrtec).

Decongestants

Many over-the-counter and prescription decongestants are available in tablet or nasal spray form. They are often used with antihistamines.

Oral and nasal decongestants -- Include Sudafed, Actifed, Afrin, Neo-Synephrin. Some decongestants may contain pseudoephedrine, which can raise blood pressure. People with high blood pressure or enlarged prostate should not take drugs containing pseudoephedrine. Nasal decongestants can cause "rebound congestion," where the nasal passages swell. Avoid using nasal decongestants for more than 3 days in a row, unless specifically instructed by your doctor, and do not use them if you have emphysema or chronic bronchitis.

Leukotreine modifiers

These prescription drugs block the production of leukotreines, which are inflammatory chemicals produced by the body. They are taken once a day and do not cause sleepiness, and are also used to treat allergic asthma. Leukotreine modifiers include montelukast (Singulair) and zafirlukast (Accolate).

Cromolyn sodium (NasalCrom)

This over-the-counter nasal spray prevents the release of histamine and helps relieve swelling and runny nose. It is most effective when taken before symptoms start and may needed to be used several times a day.

Nasal atropine

Ipratropium bromide (Atrovent) is a prescription nasal spray that can help relieve a very runny nose. People with glaucoma or an enlarged prostate should not use Atrovent.

Antihistamine eye drops -- relieve both nasal and eye symptoms; examples include azelastine, olopatadine, ketotifen, and levocabastine
Decongestant eye drops -- such as phenylephrine and naphazoline
Combination antihistamine/decongestants

Eye drops may cause stinging or even headache.

Other Treatments

Allergy shots (immunotherapy) are often recommended to anyone 7 years and older who has severe allergy symptoms or who also has asthma. Immunotherapy accustoms the immune system to allergens through regular injections of small doses of an allergen over a long period of time.

Nutrition and Dietary Supplements

Some people with allergic rhinitis also have food allergies. If you have any food allergies, eliminate those items from your diet. Even if you don't have a food allergy, cutting back on foods that may contribute to inflammation (such as meats, dairy products, sugar, and highly processed foods) may improve your symptoms.

Lactobacillus acidophilus -- One small study suggests that L. acidophilus, a type of "friendly" bacteria, might help reduce allergic reaction to pollen. More study is needed.
Quercetin -- Quercetin is a flavonoid, a plant pigment responsible for the colors found in fruits and vegetables. In test tubes, it inhibits the production and release of histamine, which causes allergy symptoms of allergic rhinitis, such as a runny nose and watery eyes. However, there is not yet much evidence that quercetin would work the same way in humans. More studies are needed.
Spirulina -- Preliminary test tube and animal studies suggest that spirulina, a type of blue-green algae, may help protect against harmful allergic reactions. Spirulina prevents the release of histamines, which contribute to symptoms of allergic rhinitis. Research on people is needed.
Vitamin C (2,000 mg per day) -- Vitamin C has antihistamine properties and some preliminary research suggested it might help reduce allergy symptoms. But another placebo-controlled trial failed to show any effect on symptoms.

Herbs

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects and can interact with other herbs, supplements, or medications. For these reasons, you should take herbs only under the supervision of a health care practitioner.

Butterbur (Petasites hybridus, 500 mg per day) -- Butterbur has been used traditionally to treat asthma and bronchitis and to reduce mucus, and several scientific studies show that it can be helpful. One study of 125 people with hay fever found that an extract of butterbur was as effective as Zyrtec. Another study compared butterbur to Allegra with similar findings. Both studies were small, however, so more research is needed. It hasn't been established whether taking butterbur longer than 12 - 16 weeks is safe. Butterbur can cause stomach upset, headache, and drowsiness. Pregnant and breastfeeding women, and young children, should not take butterbur.
Goldenseal (Hydrastis canadensis) -- Goldenseal is sometimes included in herbal remedies for allergic rhinitis. Laboratory studies suggest that berberine, the active ingredient in goldenseal, has antibacterial and immune-enhancing properties. But there is no evidence that it is effective specifically for allergic rhinitis.
Stinging nettle (Urtica dioica, 600 mg per day for one week) -- Stinging nettle has been used traditionally for treating a variety of conditions, including allergic rhinitis. But studies so far are lacking. Only one small study suggested that stinging nettle might help relieve symptoms of allergic rhinitis. Pregnant women and young children should not take stinging nettle. Talk to your doctor before taking stinging nettle if you take blood pressure medication, anticoagulants (blood thinners), diuretics (water pills),or have diabetes.

Acupuncture

Some evidence suggests that acupuncture may be a useful complementary or alternative treatment option for people with allergic rhinitis, although not all studies have found any benefit. In one study that included 45 people with hay fever, acupuncture was as effective as antihistamines in improving symptoms, and the beneficial effects appeared to last longer. However, a controlled trial that compared acupuncture to placebo (sham acupuncture) found no real benefit. One study suggested that combining acupuncture with traditional Chinese herbs did help relieve symptoms.

Homeopathy

Although few studies have examined the effectiveness of specific homeopathic therapies, professional homeopaths may consider the following remedies for the treatment of allergic rhinitis symptoms based on their knowledge and experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type -- your physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.

Nux vomica -- for stuffiness with nasal discharge, dry, ticklish, and scraping nasal sensations with watery nasal discharge and a lot of sneezing; an appropriate person for this remedy is irritable and impatient.
Arsenicum album -- for stuffiness with copious, burning nasal discharge and violent sneezing; an appropriate candidate for Arsenicum feels restless, anxious, and exhausted.
Allium cepa -- for frequent sneezing, a lot of irritating nasal discharge and tearing eyes; this person tends to feel thirsty.
Euphrasia -- for bland nasal discharge, with stinging, irritating tears; a suitable person for this remedy has worse nasal symptoms when lying down.

Traditional Chinese Medicine

Biminne

Biminne is a Chinese herbal formula used to treat allergic rhinitis. In a study of 58 people with year-round allergic rhinitis, biminne relieved at least some symptoms in most of the participants. Participants took the formula five times a day for 12 weeks, and they still showed the benefit of biminne even after one year. It is not known how biminne works, or if it is safe to use for extended periods. Biminne includes these herbs:

Chinese skullcap (Scutellaria baicalensis)
Ginkgo biloba
Horny goat weed (Epimedium sagittatum)
Schizandra chinensis
Japanese apricot (Prunus mume)
Ledebouriella divaricata
Astragalus (Astragalus membranaceus)

Other Considerations

Using some nasal sprays for long periods of time can make your allergic rhinitis worse. Call your health care provider if you develop severe symptoms, if previously successful treatment no longer works, or if symptoms do not respond to treatment.

Pregnancy

If you are pregnant or breastfeeding, avoid the following:

Decongestants without discussing with your physician
Stinging nettle
Chinese skullcap
Butterbur (Petasites) extracts
Goldenseal
High doses of vitamin C

Warnings and Precautions

Do not take stinging nettle if you take blood pressure medication, anticoagulants (blood thinners), diuretics (water pills), or have diabetes without talking to your doctor first.

You should not use goldenseal over a long period of time, and you should avoid it if you have high blood pressure.

Skullcap has sedative properties, and should be used with caution or not at all with antihistamines that also make you drowsy.

Prognosis and Complications

Chances are your symptoms of allergic rhinitis will be readily treated, but they will continue to appear each time you are exposed to an allergen.

Although perennial allergic rhinitis is not a serious condition, it can interfere with many important aspects of life. Depending on how severe your symptoms are, allergic rhinitis can lead to missed days from school or work. Medication may cause drowsiness and other side effects. Your allergies could also trigger other conditions, such as eczema, asthma, sinusitis, and ear infection (called otitis media). Seasonal allergies may improve as you get older.

Desensitization (allergy shots) may cause uncomfortable side effects (such as hives and rash) and may have dangerous side effects such as anaphylaxis. It often requires years of treatment and is effective in about two-thirds of cases.

Supporting Research

Anonymous. Monograph. Petasites hybridus. Altern Med Rev. 2001;6(2):207-209.

Blanc PD, Trupin L, Earnest G, Katz PP, Yelin EH, Eisner MD. Alternative therapies among adults with a reported diagnosis of asthma or rhinosinusitis : data from a population-based survey. Chest. 2001;120(5):1461-1467.

Blumenthal M, Goldberg A, Brinckmann J. Herbal Medicine: Expanded Commission E Monographs. Newton, MA: Integrative Medicine Communications; 2000.

Calder PC, Miles EA. Fatty acids and atopic disease. Pediatr Allergy Immunol. 2000;11 Suppl 13:29-36.

Chari P, Biwas S, Mann SBS, Sehgal S, Mehra YN. Acupuncture therapy in allergic rhinitis. Am J Acupunct. 1988;16(2):143-147.

Chatzi L, Apostolaki G, Bibakis I, Skypala I, Bibaki-Liakou V, Tzanakis N,et al. Protective effect of fruits, vegetables and the Mediterranean diet on asthma and allergies among children in Crete. Thorax. 2007 Aug;62(:677-83.

Cummings S, Ullman D. Everybody's Guide to Homeopathic Medicines. 3rd ed. New York, NY: Penguin Putnam; 1997:68-70, 233-234.

Foster S, Tyler VE. Tyler's Honest Herbal. 4th ed. New York: The Haworth Herbal Press; 1999:195-197.

Hu G, Walls RS, Bass D, et al. The Chinese herbal formulation biminne in management of perennial allergic rhinitis: a randomized, double-blind, placebo-controlled, 12-week clinical trial. Ann Allergy Asthma Immunol. 2002 May;88(5):478-487.

JAMA Patient Page. How much vitamin C do you need? JAMA. 1999;281(15):1460.

Johnston CS. Recommendations for vitamin C intake. JAMA. 1999;282(22):2118-2119.

Johnston CS, Martin LJ, Cai X. Antihistamine effect of supplemental ascorbic acid and neutrophil chemotaxis. J Am Coll Nutr. 1992;11:172-176.

Jonas WB, Jacobs J. Healing with Homeopathy: The Doctor's Guide. New York, NY: Warner Books;1996:201-204.

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Review Date:
9/25/2007
Reviewed By:
Steven D. Ehrlich, N.M.D., private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.

A.D.A.M. Copyright

adam.com

Asthma in adults

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

In This Report

Highlights
Introduction
Symptoms
Causes
Prognosis
Risk Factors
Diagnosis
Treatment
Quick-Relief Medications...
Long-Term Relief Medication...
Other Treatments
Managing Asthma
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Drug Warning

In 2007, the FDA requested the manufacturers of omalizumab (Xolair) to include a “boxed warning” emphasizing that this drug may cause a severe and life-threatening allergic reaction (anaphylaxis). Omalizumab is approved for patients who have moderate-to-severe asthma related to allergies and whose symptoms are not controlled by inhaled corticosteroids. It is given by injection in a doctor’s office every 2 - 4 weeks. The warning indicates that patients may develop anaphylaxis after any dose of omalizumab, even if they had no reaction to the initial shot. Health care providers need to observe patients carefully for 2 hours after they receive an omalizumab injection. However, because an allergic reaction can occur up to 24 hours after the injection, patients need to know the signs and symptoms of anaphylaxis and how to self-administer emergency treatment.

Anaphylaxis symptoms include:

Difficulty breathing
Chest tightness
Dizziness
Fainting
Itching and hives
Swelling of the mouth and throat

Drug Approval

In 2006, the FDA approved budesonide/formoterol (Symbicort). Symbicort combines a corticosteroid and a long-acting beta2-agonist into a single inhaler.

Long-Acting Beta2-Agonists

Long-acting beta2-agonist drugs, such as salmeterol (Serevent Diskus) and formoterol (Foradil Aerolizer), may worsen asthma symptom severity and increase the risk for asthma-related death, indicates a 2006 review in the Annals of Internal Medicine.
Products that contain salmeterol and formoterol now have strengthened warning labels detailing these risks.

Asthma and Heartburn

Studies have suggested an association between heartburn, also known as gastroesophageal reflux disease (GERD), and asthma that gets worse at night (nocturnal asthma). A 2006 study tested whether a proton pump inhibitor drug might help improve morning breathing in patients who suffer from these two conditions. The results suggested that the drug provided only a moderate benefit.

Introduction

Air passes into the lungs and flows through progressively smaller airways called bronchioles. The lungs contain millions of these airways.
All bronchioles lead to alveoli, which are microscopic sacs where oxygen and carbon dioxide are exchanged.

The major features of the lungs include the bronchi, the bronchioles, and the alveoli. The alveoli are the microscopic blood vessel-lined sacks in which oxygen and carbon dioxide gas are exchanged.

Asthma is a chronic condition in which these airways undergo changes when stimulated by allergens or other environmental triggers. Such changes appear to be two specific responses:

The hyperreactive response (also called hyperresponsiveness)
The inflammatory response

These actions in the airway cause patients to cough, wheeze, and experience shortness of breath (dyspnea), the classic symptoms of asthma.

In the hyperreactive response, smooth muscles in the airways of the lungs constrict and narrow excessively in response to inhaled allergens or other irritants. Everyone's airways respond by constricting when exposed to allergens or irritants, but a special hyperreactive response occurs in people with asthma:

When people without asthma breathe in and out deeply, the airways relax and open to rid the lungs of the irritant.
When people with asthma try to take those same deep breaths, their airways do not relax and narrow, causing patients to pant for breath. Smooth muscles in the airways of people with asthma may have a defect, perhaps a deficiency in a critical chemical that prevents the muscles from relaxing.

The hyperreactive stage is followed by the inflammatory response, which generally contributes to asthma in the following way:

In response to allergens or other environmental triggers, the immune system delivers white blood cells and other immune factors to the airways.
These so-called inflammatory factors cause the airways to swell, to fill with fluid, and to produce a thick sticky mucus.
This combination of events results in wheezing, breathlessness, inability to exhale properly, and a phlegm-producing cough.

Click the icon to see an image of a normal bronchiole versus an asthmatic bronchiole.

Inflammation appears to be present in the lungs of all patients with asthma, even those with mild cases, and plays a key role in all forms of the disease.

Symptoms

Asthma symptoms vary in severity from occasional mild bouts of breathlessness to daily wheezing that persists despite taking large doses of medication. After exposure to asthma triggers, symptoms rarely develop abruptly but progress over a period of hours or days. Occasionally, the airways have become seriously obstructed by the time the patient calls the doctor.

The classic symptoms of an asthma attack include:

Wheezing when breathing out is nearly always present during an attack. Usually the attack begins with wheezing and rapid breathing, and, as it becomes more severe, all breathing muscles become visibly active.
Shortness of breath (dyspnea). Shortness of breath is a major source of distress in patients with asthma. However, the severity of this symptom does not always reflect the degree to which lung function is impaired. Some patients are not even aware that they are experiencing shortness of breath. Such patients are at particular risk for very serious and even life-threatening asthma attacks, since they are less conscious of symptoms. Those at highest risk for this effect tend to be older, female, and to have had the disease for a longer period of time.
Coughing. In some people, the first symptom of asthma is a nonproductive cough. Some patients find this cough even more distressing than wheezing or sleep disturbances.
Chest tightness or pain. Initial chest tightness without any other symptoms may be an early indicator of a serious attack.
Neck muscles may tighten, and talking may become difficult or impossible.
Rapid heart rate.
Sweating.
Chest pain occurs in about 75% of patients. It can be very severe, although the pain's intensity is not necessarily related to the severity of the asthma attack itself.

The end of an attack is often marked by a cough that produces thick, stringy mucus. After an initial acute attack, inflammation lasts for days to weeks, often without symptoms. (The inflammation itself must still be treated, however, because it usually causes relapse.)

Causes

Asthma has dramatically risen worldwide over the past decades, particularly in developed countries, and experts are puzzled over the cause of this increase. The mechanisms that cause asthma are complex and vary among population groups and even from individual to individual. Many asthma sufferers have allergies, and some researchers are targeting common factors in both these conditions. Not all people with allergies have asthma, however, and not all cases of asthma can be explained by allergic response.

Asthma is most likely to be caused by a convergence of factors that can include genes and various environmental and biologic triggers (infections, dietary patterns, hormonal changes in women, and allergens).

Nearly half of adults with asthma have an allergy-related condition, which, in most cases developed first in childhood. (In patients who first develop asthma during adulthood, the allergic response usually does not play a strong causal role.) Important irritants or allergens include:

Dust mites, specifically mite feces, which are coated with enzymes that contain a powerful allergen. These are the primary allergens in the home.
Animal dander.
Pollen. An asthma attack from an allergic response to pollen is more likely to occur during extreme air changes, such as thunderstorms. Major weather changes, such as El Nino, can affect the timing of allergy seasons. For example, in 1998, when the effects of El Nino were very strong, allergy and asthma attacks occurred earlier and were markedly increased.
Molds. A 2002 study suggested that molds might produce a worse asthma attack in adults than other allergens.
Fungi.
Cockroaches. Cockroaches are major asthma triggers and may reduce lung function even in people without a history of asthma.
Fossil Fuels. Certain chemicals may trigger allergic rhinitis. Some experts believe that refined fossil fuels, such as diesel fuel and particularly kerosene, may be important triggers for allergic rhinitis. And, in people who already have allergies or asthma, exposure to such fossil fuels may worsen symptoms.

The Allergic Process. The allergic process, called atopy, and its connection to asthma is not completely understood. It involves various airborne allergens or other triggers that set off a cascade of events in the immune system leading to inflammation and hyperreactivity in the airways. One description is as follows:

The conductor in an orchestra of immune factors that contribute to allergies and asthma appears to be a category of white blood cells known as helper T cells, in particular a subgroup called Th2 cells.
Th2 cells overproduce interleukins (ILs), immune factors that are molecular members of a family called cytokines, which are involved in the inflammatory process.
Interleukins 4, 9, and 13 may be responsible for a first-phase asthma attack. These interleukins stimulate the production and release of antibody groups known as immunoglobulin E (IgE). (People with both asthma and allergies appear to have a genetic predisposition for overproducing IgE.)
During an allergic attack, these IgE antibodies can bind to special cells in the immune system called mast cells, which are generally concentrated in the lungs, skin, and mucous membranes. This bond triggers the release of several active chemicals, importantly potent molecules known as leukotrienes. These chemicals cause airway spasms, overproduce mucus, and activate nerve endings in the airway lining.
Another cytokine, interleukin 5, appears to contribute to a late-phase inflammatory response. This interleukin attracts white blood cells known as eosinophils. These cells accumulate and remain in the airways after the first attack. They persist for weeks and mediate the release of other damaging particles that remain in the airways.

The Immune Response. Researchers are investigating the role that T cells play in asthma. T cells are white blood cells that are involved in the immune response. Researchers had focused on the T cell called type 2 helper (Th2) cells. However, a 2006 breakthrough study in the New England Journal of Medicine suggested that a different type of T cell may play a stronger role in asthma than previously thought.

Growth Factors. Compounds known as vascular endothelial growth factor (VEGF) have been observed in the airways of patients with asthma. VEGF is a powerful promoter of cell growth in blood vessel linings, and some researchers believe it may be major factor in remodeling.

About one-third of all persons with asthma share this condition with another member of their immediate family. Asthma may be more likely to pass to children from their mother than from their father. Both allergies and asthma are strongly associated with hereditary factors, sharing certain genetic markers, but they are not always inherited together.

Hormones or changes in hormone levels appear to play a role in the severity of asthma in women.

Menstrual-Related Asthma. Between 30 - 40% of women with asthma experience fluctuations in severity that are associated with their menstrual cycle. One study indicated that women with menstrually associated asthma tend to have the following characteristics:

Older age
Had asthma for a long time
Had severe asthma attacks that were likely to occur 3 days before and 4 days into the menstrual period

Oral contraceptives (OCs) theoretically should help asthma sufferers by leveling out hormonal changes, but they do not appear to have much effect. (There have been a few reports of asthma exacerbation with OCs, but these are uncommon events.)

Asthma during Pregnancy. During pregnancy, one-third of women with asthma suffer more from the condition, one-third suffer less, and one-third experience no difference in severity. Some studies suggest that expectant mothers carrying a female baby tend to have more severe asthma symptoms than do those who are bearing a male.

Menopause and Asthma. Around the time of menopause (called perimenopause) when estrogen declines, the risk for hospitalization in women with asthma increases fourfold compared to previous years. Studies have not demonstrated that hormone replacement therapy (HRT), which contains estrogen, has much benefit.

About 10% of adults and some fewer children have aspirin-induced asthma (AIA). With this condition, asthma gets worse when patients take aspirin. Aspirin is one of the drugs known as nonsteroidal anti-inflammatory drugs (NSAIDs). Although aspirin is used to reduce inflammation in other disorders, it appears to have the opposite effect in many asthma cases. It is not wholly known why this occurs. AIA often develops after a viral infection. It is a particularly severe asthmatic condition, associated with up to 25% of asthma-related hospitalizations. In about 5% of cases, aspirin is responsible for a syndrome that involves multiple attacks of asthma, sinusitis, and nasal congestion. Such patients also often have polyps (small benign growths) in the nasal passages.

Patients with aspirin-induced asthma (AIA) should avoid aspirin and most likely other NSAIDs, including ibuprofen (Advil) and naproxen (Aleve).

Exercise-induced asthma (EIA) is a limited form of asthma in which exercise triggers coughing, wheezing, or shortness of breath.

Asthma occurs primarily at night (nocturnal asthma) in as many as 75% of patients with asthma. Attacks often occur between 2 and 4 a.m. Factors that might play role in nocturnal asthma may include one or more of the following:

Chemical and temperature changes in the body during the night that increase inflammation and narrowing of the airways
Delayed allergic responses from exposure to allergens during the day
The wearing off of inhaled medications toward the early morning
An increase in acid reflux (back up of stomach acid) that causes airways to narrow
Postnasal drip that occurs during sleep
Conditions relating to sleep, such as sleep apnea or sleeping on one's back, which may worsen any asthma attack that occurs at night

Some experts believe that nocturnal asthma may actually be a unique form, with its own specific biologic mechanisms that occur only at night and which reduce natural steroid hormones (which block inflammation).

Infections. The role of infections in asthma is complicated. Respiratory infections may play a role in some cases of adult-onset asthma, but may be protective against asthma in small children. (In both children and adults with existing allergic asthma, however, an upper respiratory tract infection often worsens an attack.)

Researchers are particularly interested in the organisms Chlamydiapneumoniae and Mycoplasmapneumoniae adenovirus. They are major causes of both mild and serious respiratory infections and are becoming important suspects in many cases of severe adult asthma. (If such respiratory infections occur in young children, they are unlikely to affect adult-onset asthma.)

In one study, patients whose asthma occurred after infections had more severe conditions than those whose asthma was due to other causes. The infection-initiated asthma, however, lasted only 5.6 years compared to 13.3 years in the non-infection group.

In any age group, respiratory infections worsen existing asthma in people who have it already. Rhinovirus (the common cold virus) has been reported to be the most common infection associated with asthma attacks. In one study, it was associated with 61% of asthma exacerbations in children and 44% in adults. Some research suggests that colds promote allergic inflammation and increase the intensity of airway responsiveness for weeks.

GERD. At least half of patients with asthma have gastroesophageal reflux disease (GERD), the cause of heartburn. It is not entirely clear which condition causes the other or whether they are both due to common factors.

Heartburn is a condition where the acidic stomach contents back up into the esophagus causing pain in the chest area. This reflux usually occurs because the sphincter muscle between the esophagus and stomach is weakened. Standing or sitting after a meal can help reduce the reflux that causes heartburn. Continuous irritation of the esophagus lining as in gastroesophageal reflux disease is a risk factor for the development of adenocarcinoma.

Some theories for the causal connection between GERD and asthma are:

Acid leaking from the lower esophagus in GERD stimulates the vagus nerve, which runs through the gastrointestinal tract. This stimulated nerve triggers the nearby airways in the lung to constrict, causing asthma symptoms.
Acid backup that reaches the mouth may be inhaled into the airways (aspirated). Here, the acid triggers a reaction in the airways that cause asthma symptoms.

GERD is sometimes hard to detect and might be a contributor in the following patients:

Those who do not respond to asthma treatments
Those whose asthma attacks follow episodes of heartburn
Those whose attacks worsen after eating or exercise
Those whose coughs follow episodes of acid reflux. (One study found that GERD was associated with about half of the episodes of coughs and wheezes in patients with asthma.)

Treating GERD symptoms with anti-acid drugs may resolve asthma in some (but not all) patients who share both conditions. A small 2005 study found that while GERD was common in patients with asthma, treatment of GERD had no effect on asthma symptoms. A 2006 study indicated that the proton pump inhibitor esomeprazole (Nexium) slightly helped patients who had both GERD and asthma symptoms that occurred at night. [See In-Depth Report #85: Heartburn and gastroesophageal reflux disease.]

Click the icon to see an image of sinusitis.

EIA is triggered only by exercise and is distinct from ordinary allergic asthma in that it does not produce a long duration of airway activity, as allergic asthma does. (It should be noted that some people have both forms of asthma.) People who have only EIA do not appear to require long-term maintenance therapy. A study of military recruits with EIA also reported that the condition does not hinder a person's overall physical performance.

Medications

Cromolyn, a mild anti-inflammatory drug, or short-acting beta2-agonists have been the treatments of choice for preventing EIA. Newer approaches for people who work out regularly include pretreatment with long-acting beta2-agonists, such as salmeterol (Serevent), or the regular use of inhaled corticosteroids.

Hints for Reducing EIA

EIA occurs only after exercise and is more likely to occur with regularly paced activities in cold, dry air. The following are some suggestions for reducing its impact:

Warm-up and cool-down periods are important.
Patients with EIA might do better with activities that involve short bursts of exercise (tennis, football) than with exercises involving long-duration regular pacing (cycling, soccer, and distance running).
Breathing through a scarf or through the nose helps warm up the airways.
Some evidence suggests that restricting dietary salt might help reduce EIA.

Click the icon to see an image of exercise-induced asthma.

Prognosis

About 450,000 American adults are admitted to an emergency room with asthma each year. The number of deaths from asthma increased from about 2,900 in 1908 to a high of 5,667 in 1996. The numbers appear to be declining slightly, and in 2002 about 4,260 people died because of asthma. Death from asthma is still a very uncommon event, considering that an estimated 20 million people in the U.S. have this condition. Most deaths from asthma, even when they occur in elderly adults, are preventable. It is very rare for a person who is receiving proper treatment to die of asthma. And, studies suggest that the use of inhaled corticosteroids can reduce the risk for death by 90%. In spite of this and similar research, these important drugs are greatly underused.

About 55% of U.S. deaths from asthma occur among the elderly (over age 65), and an estimated 25% occur in adults aged 45 - 64. Women have a higher risk for fatal asthma than men. Being poor is also a significant risk factor for severe asthma. Hispanics and African Americans are at higher risk for death from asthma than Caucasians. Other specific risk factors for fatal asthma include:

Previous history of respiratory failure
Frequent visits to the emergency room
Lack of continuous care and poor compliance with medications
Having stopped treatment, particularly withdrawal from corticosteroids
Having an emotional or psychiatric disorder. (Some evidence suggests that depression, anxiety, and stressful life situations can worsen asthma.)
Being a drug abuser
Being in a lower socioeconomic and educational group

The following signs and symptoms may indicate a life-threatening situation:

As the chest labors to bring enough air into the lungs, breathing often becomes shallow.
Lacking sufficient oxygen, the skin becomes bluish.
The flesh around the ribs of the chest appears to be sucked in.
The patient may begin to lose consciousness.

It should strongly be noted that early symptoms or lack thereof do not always reflect the ultimate severity of an attack. In fact, some studies suggest that people at high risk for fatal or near-fatal asthma attacks are those with poor awareness of their own reduced ability to breathe and who are therefore slow in seeking help. Those at highest risk for this effect tend to be older, female, and have had the disease for a longer period of time. Monitoring peak flow rates is an important management component since it provides a more accurate assessment of lung function than symptoms alone.

The severity of asthma is graded using the following categories: mild intermittent and mild, moderate, and severe persistent. A patient in any of these categories, even mild intermittent, can still experience a severe and even life-threatening attack. In fact, according to one report, 30% of asthma deaths occur in patients with mild asthma.

Asthma is usually chronic, although it occasionally goes into long periods of remission. Long-term outlook generally depends on severity:

In mild-to-moderate cases, asthma can improve over time, and many adults even become symptom free.
Even in some severe cases, adults may experience improvement depending on the degree of obstruction in the lungs and the timeliness and effectiveness of treatment.
In about 10% of severe persistent cases, changes in the structure of the walls of the airways lead to progressive and irreversible problems in lung function, even in aggressively treated patients.

Lung function declines faster than average in people with asthma, particularly in those who smoke and in those with excessive mucus production (an indicator of poor treatment control). Overall, one study reported that 72% of men and 86% of women with asthma had symptoms 15 years after an initial diagnosis. Only 19% of these people, however, were still seeing a doctor, and only 32% used any maintenance medication.

Patients who develop occupational asthma often experience asthmatic symptoms for years, even after avoiding the harmful triggers. Improvement does occur over time in most people who leave such jobs.

Emotional Problems. Even when it is not life-threatening, asthma is debilitating and frightening. It significantly lowers the quality of life.

Sleep Disorders. Sleeplessness and daytime sleepiness are common problems. Studies indicate that between 80 - 93% of people with asthma have sleeping problems about three times a week. In one poll, 40% missed work an average of 11 days a year because of sleep disturbance. Asthma has been associated with snoring and obstructive sleep apnea, a condition in which blockage of the upper airway causes the sleeper to temporarily stop breathing, then resume with a gasp, often many times during each hour of sleep.

Asthma and Pregnancy. Uncontrolled asthma in pregnant women puts them at higher risk for complications that can include early labor, hypertension, gestational diabetes, and hemorrhage. Asthma also places the babies at risk for lower birth weight and breathing disorders. Teenage mothers with asthma face higher risks than older women. Fortunately, studies indicate that most asthma drugs are safe to take during pregnancy, and good control of asthma reduces these risks to normal levels.

New guidelines released in 2005 by the National Asthma Education and Prevention Program (NAEPP) emphasize that most asthma medications are safe for pregnant women. The guidelines recommend that pregnant women with asthma have albuterol available at all times. Inhaled corticosteroids should be used for persistent asthma. Patients whose persistent asthma does not respond to standard dosages of inhaled corticosteroids may require a higher dosage or the addition of a long-acting beta agonist to their drug regimen. For severe asthma, oral corticosteroids may be required. The NAEPP notes that while it is not clear if oral corticosteroids are safe for pregnant women, uncontrolled asthma poses an even greater risk for a woman and her fetus.

Heart Disease. There have been some reports of an association between asthma and a heightened risk for heart disease. Some experts believe that the inflammatory process may be the common factor linking the two conditions, although there is no evidence to date confirming any causal association.

Risk Factors

According to a major national 2001 survey, American adults have a 10% lifetime risk for developing asthma. As of 2002, an estimated 20 million adults had the disorder. Between 1980 - 1996 the prevalence of asthma increased by nearly 74%, but it may be stabilizing. Other respiratory diseases, sinusitis, and ear infections are also on the rise, suggesting that airborne or environmental factors may be at work that affects all of these conditions, including asthma.

Before puberty, asthma occurs more often in males, but after adolescence, it appears to be more common in females. In adults with similar cases of actual airway obstruction, women are likely to report more severe symptoms than men are. In addition, women may be at much greater risk of death from asthma than men.

In both adults and children, the incidence of obesity and asthma has been increasing in parallel over recent years. Studies report a strong association between the two conditions. Some experts suggest that excess weight pressing on the lungs may trigger the hyperreactive response in the airways typical of asthma. Others believe that asthma leads to obesity by inhibiting physical activity, although several studies have found no difference in activity levels between people with or without asthma. Some studies suggest that many obese people may be misdiagnosed as having asthma when in fact they are simply short of breath, possibly because of the increased effort required for breathing.

In one study of elderly people with severe adult-onset asthma, smoking was the most significant risk factor for developing this condition. Smoking, in any case, contributes to decline in lung function in everyone.

Urban Life and Poverty. African Americans have higher rates of asthma than Caucasians or other ethnic groups. They are also more likely to die of the disease. Ethnicity and genetics, however, are less likely to play a role in these differences than socioeconomic differences, such as having less access to optimal health care. Poverty is a consistent risk factor in most studies. Both the elderly and the urban poor have the highest risk for severe asthma and death. Urban life, in fact, has been associated with a higher risk for asthma in all income groups and among both children and adults. Twin studies also suggest that people who have lower educational levels (as well as those who exercise less) are at higher risk for adult-onset asthma, further suggesting a link to lower economic status.

Geographical Differences. Asthma rates vary widely among different populations regardless of socioeconomic or other factors. For example, asthma and hospitalization rates are dramatically higher in New York Puerto Ricans than in Hispanic Americans who live in Los Angeles or the Southwest. Among the U.S. states, rates are lowest in Louisiana and highest in Maine.

There are significant differences among nations. In a 2001 study of 22 nations, the countries with the highest asthma rates were Britain, Ireland, Australia, New Zealand, and the U.S. (According to another study, asthma rates are also significantly higher in Canadian adults than they are in comparable European groups.) Low rates were reported in Iceland, Norway, Spain, Germany, Italy, Algeria, India, and Eastern European nations. The reasons for these variations are still unknown.

Diagnosis

When asthma is suspected, the patient should describe for the doctor any pattern related to the symptoms and possible precipitating factors, including:

Whether symptoms are more frequent during the spring or fall (allergy seasons).
Whether exercise, a respiratory infection, or exposure to cold air has ever triggered an attack.
Any family history of asthma or allergic disorders, such as eczema, hives, or hay fever.
Any occupational or long-term exposure to chemicals. Early detection of occupational asthma is very important. If symptoms improve on weekends and vacation and are worse at work, the job is likely to be the source of the asthma, although this is not always the case. Asthma is common, and exacerbation at work may be coincidental.

A number of disorders may cause some or all of the symptoms of asthma:

Asthma and chronic obstructive lung diseases (chronic bronchitis and emphysema) affect the lungs in similar ways and, in fact, may all be present in the same person. Unlike other chronic lung conditions, asthma usually first appears in patients younger than age 30 and with chest x-rays that are normal. Still, it may be difficult to distinguish these disorders in some adults with late onset asthma.
Panic disorder can coincide with asthma or be confused with it.
Gastroesophageal reflux disorder (GERD) is a common companion in asthma and may affect treatment.
Other diseases that must be considered during diagnosis are pneumonia, bronchitis, severe allergic reactions, pulmonary embolism, cancer, heart failure, tumors, psychosomatic illnesses, and certain rare disorders (such as tapeworm and trichomoniasis).

If symptoms and a patient's history suggest asthma, the doctor will usually perform tests known as pulmonary function tests to confirm the diagnosis and determine the severity of the disease.

Using a spirometer, an instrument that measures the air taken into and exhaled from the lungs, the doctor will determine several values:

1. Vital capacity (VC), which is the maximum volume of air that can be inhaled or exhaled.

2. Peak expiratory flow rate (PEFR), commonly called the peak flow rate, which is the maximum flow rate that can be generated during a forced exhalation.

3. Forced expiratory volume (FEV1), which is the maximum volume of air expired in one second.

Spirometry is a painless study of air volume and flow rate within the lungs. Spirometry is frequently used to evaluate lung function in people with obstructive or restrictive lung diseases such as asthma or cystic fibrosis.

If the airways are obstructed, these measurements will fall. Depending on the results, the doctor will take the following steps:

If measurements fall, the doctor typically asks the patient to inhale a bronchodilator. This drug is used in asthma to open the air passages. The measurements are taken again. If the measurements are more normal, the drug likely has cleared the airways and a diagnosis of asthma is strongly suspected.
If measurement results fail to show airway obstruction, but asthma is still suspected, the doctor may perform a challenge test. This involves administering a specific drug (histamine or methacholine) that usually increases airway resistance only when asthma is present. The challenge test may be quite useful in ruling out occupational asthma. It is not always accurate, particularly in patients whose only symptom is persistent coughing.
Administering cold air is another method for inducing airway resistance. This test is very accurate for ruling out asthma, but it is not sensitive enough to accurately identify adults who actually have asthma.

The patient may be given skin or blood allergy tests, particularly if a specific allergen is suspected and available for testing. Allergy skin tests may be the best predictive tests for allergic asthma, although they are not recommended for people with year-round asthma.

Click the icon to see an image of allergy testing.

Tests that either rule out other diseases or obtain more information about the causes of asthma include:

A complete blood count.
Chest and sinus x-rays.
Computed tomography (CT) scans. CT scans may be helpful in certain cases, such as for determining wall thickness in airways in patients who are difficult to treat, which could signify a higher risk for lung damage.
Examination of the patient's sputum for eosinophils (white blood cells that in high levels are associated with severe allergic asthma). One 2002 study suggested that treatment goals based on achieving a normal eosinophil count might effectively manage asthma.
Researchers are investigating measurements of certain chemicals in sputum or exhaled air that indicate airway inflammation. Such chemical markers include nitric oxide and hydrogen peroxide. For example, high levels of nitric oxide in exhaled air is proving to be a simple and noninvasive way of diagnosing asthma.
If aspirin-induced asthma (AIA) is suspected, a non-invasive test called acoustic rhinometry may be useful. A solution of lysine acetylsalicylic acid (L-ASA) is instilled into the patient's nostril. Patients who experience symptoms such as sneezing, itching, congestion, and secretion are likely to have AIA.

Treatment

Beta2-agonists are the standard therapy. They may be administered with a nebulizer (a device that administers the drug in a fine spray) or given hourly with an inhaler. Studies are suggesting the use of an inhaler is equally or possibly more effective than a nebulizer. Intravenous delivery is not recommended in most cases.
A corticosteroid (commonly called a steroid) given within the first hour helps reduce the need for hospitalization. Steroids are typically administered intravenously or as an injection in adults. Lower doses work as well as higher ones in these situations.
Intravenous magnesium opens airways and is an important emergency treatment for patients with very severe asthma.
Oxygen is usually administered, and can be life-saving in severe cases.
In life-threatening situations, the patient may require mechanical ventilation.
Antibiotics are not useful for asthma attacks if there is no strong evidence of the presence of a bacterial infection. (Viral infections, most often colds and the flu, are more likely to trigger an asthma attack. In such cases, antibiotics do not appear to be beneficial and may have adverse effects.)

Discharge and Relapse After Hospitalization. It typically takes 3 - 4 hours to determine if a patient can be safely sent home or if they need to stay in the hospital. Patients are generally discharged under the following circumstances:

When symptoms are gone or are minimal, and
The peak expiratory flow rate is 70% or more of the predicted rate

Discharged patients generally take oral corticosteroids for 5 - 7 days. Despite reasonable precautions, about 20% of patients relapse within 2 weeks, although the risk is very low if they keep taking their medication after they leave.

Avoiding allergens, following appropriate drug treatments, and home monitoring are key elements in preventing dangerous asthma attacks and hospitalization. A combination of medications is important for both treating and preventing asthma attacks. In addition, good communication between the doctor and patient is a key factor in a successful management program. Written action plans, which instruct individual patients how to properly respond to changes in their unique symptoms, are a very important element in successful self-management of asthma.

Medications for asthma fall into two categories:

Rescue Medication. Medications that open the airways (bronchodilators, or inhalers) are used to quickly relieve any moderate or severe asthma attack. These drugs are usually short-acting beta-adrenergic agonists (beta2-agonists). Other drugs used in special cases include corticosteroids taken by mouth and anticholinergic drugs. None of these drugs have any effect on the disease process itself. They are only useful for treating symptoms.
Maintenance Medication. Simply coping with asthma symptoms without also controlling the damaging inflammatory response is a common and serious error. For adults and children over age 5 with moderate-to-severe persistent asthma, experts now recommend inhaled corticosteroids and long-acting beta2-agonists.

Patients can greatly reduce the frequency and severity of asthma attacks by understanding the difference between coping with asthma attacks and controlling the disease over time. Unfortunately, many patients do not understand the difference between medications that provide rapid short-term relief and those that are used for long-term symptom control. Many patients with moderate or severe asthma overuse their short-term medications and underuse their corticosteroid medications. The overuse of bronchodilators can have serious consequences; not using steroids can lead to permanent lung damage.

Patients need to understand that asthma symptoms can change quickly over time and that treatment strategies may need to change. In 2005, the two leading U.S. allergy associations published joint guidelines on controlling asthma. The guidelines emphasize that asthma treatment decisions need to be made on an individual basis. It is important that patients have a close relationship with their doctor. The doctor needs to evaluate a patient’s asthma symptoms at each and every visit to determine if there should be any changes in medication.

According to the guidelines, asthma management is classified as either “well-controlled” or “not well-controlled.” Your doctor may need to change some of your medications, or increase or decrease the dosage, depending on whether your asthma is well-controlled or not well-controlled.

These are the signs of well-controlled asthma:

Asthma symptoms occur twice a week or less
Rescue bronchodilator medication is used twice a week or less
Symptoms do not cause nighttime or early morning awakening
Symptoms do not limit work, school, or exercise activities
Peak flow meter readings are normal or the patient’s personal best
Both the doctor and the patient consider the asthma to be well controlled

Most asthma drugs are inhaled using various forms of inhalers or nebulizers. Inhaled drugs must be used regularly as prescribed and the patient carefully trained in their use in order for them to be effective and safe. The basic devices are the metered-dose inhaler (MDI), breath-actuated inhalers, dry powder inhalers, and nebulizers.

MDIs have used chlorofluorocarbons (CFCs) as their propellants. CFCs are damaging to the environment. CFCs are now being replaced with other propellants (such as hydrofluoroalkane) that are equally effective to CFCs, are environmentally safe, and do not chill the device as CFCs do. Devices that don't use propellants at all are also now available.

Metered-Dose Inhaler. The standard device for administering any asthma medication has been the metered-dose inhaler (MDI). This device, particularly when used with a holding chamber, allows precise doses to be delivered directly to the lungs.

Click the icon to see an image of a holding chamber.

MDI-delivered drugs must be used regularly as prescribed, and the patient carefully trained in their use, for the drugs to be effective and safe. Some patients hold the MDI too close to their mouths, or even inside them. Others may exhale too forcefully before inhalation. The holding chamber, or spacer, allows the patient additional time to inhale the medication, improving delivery. They vary, however, in their ability to deliver medication. Often MDIs continue to deliver propellant after the drug has been used up. Patients should track their medicine and throw the device away when the last dose has been administered.

Click the icon to see an illustrated series detailing metered dose inhaler use.

Dry Powder Inhalers. Dry powder inhalers (DPIs) deliver a powdered form of beta2 agonists or corticosteroids directly into the lungs. They also do not use CFCs. Such devices include Rotahaler, Spinhaler, Turbohaler, Clickhaler, Easyhaler, Diskhaler, Discus, Twisthaler, Spiros, and others. DPIs are as effective as the older devices, and generally have a better taste and are easier to manage. They may differ among themselves, however, in their ability to deliver drugs into the airways. In one study, for example, the Turbohaler was easier to use than the Diskhaler, achieving better delivery. The Discus is another effective DPI. It has a dose counter and protects against exhalation effects.

Humidity or extreme temperatures can affect these inhalers' performance, so they should not be stored in humid places (bathroom cabinets) or locations subject to high temperatures (glove compartments during summer months).

Dry-powder may cause tooth erosion, and children are advised to rinse their mouths out right after using a DPI and to brush twice a day with a fluoride toothpaste.

Other Hand-Held Inhalers. Respimat delivers a fine-mist spray that is created by forcing the liquid medication through nozzles. It does not use any propellant.

Nebulizers. A nebulizer is a device that administers the drug in a fine spray that the patient breathes in. They are mostly used in hospital settings or when the patient cannot use an inhaler. Nebulizers may be important for delivering newer drugs used in asthma treatment.

Click the icon to see an illustrated series detailing nebulizer use.

People who self-manage their asthma using daily monitoring of peak air flow and adjusting their medications as needed have fewer hospitalizations, fewer unplanned doctors visits, and, generally, a better quality of life than those who rely only on the occasional doctor or emergency room visit to control symptoms. Doctors recommend that patients with even mild asthma monitor their own conditions.

In general, monitoring involves the following steps:

A peak flow meter is the standard monitoring device for measuring peak expiratory flow rate (PEFR).

Click the icon to see an image of a peak flow meter.

Patients with severe asthma should take PEFR readings two or three times a day. The overall goal should be to achieve less than a 20% (and ideally only 10%) variation in readings between evening and morning rates. For mild-to-moderate asthma, a single determination each morning usually suffices, but patients should check with their doctors.
It is important to use the meter at the same times each day and to stand or sit in the same position to keep an accurate record.
Patients should keep an ongoing record of their peak flow readings to help them detect worsening of their condition.
They should also record attacks, exposure to any allergens or triggers, and medications taken.
After about 2 months, patients and doctors can use the recorded data for administering medications effectively and to recognize problems before they become serious.

In general, many people fail to monitor their asthma. Experts believe that, ideally, portable monitors should be available to measure forced expiratory volume (FEV1), a more accurate gauge of lung function, and the results should be electronically transmitted to the doctor.

New monitoring devices are showing promise in accomplishing one or more of these goals, although they are not covered by most insurers. For example, the AirWatch is a handheld digital monitor that measures and displays the rate of airflow and compares it to the rates from previous days. Once a month, or whenever there is a problem, the patient plugs the device into a standard telephone jack, and the daily readings are sent to an automated data center that creates tables and charts for the patient and the doctor.


Medication Purpose	Drug Class	Generic Name	Brand Names	Administration
Quick-Relief Medications (control acute attacks)	Short-Acting Beta2 Agonists	Albuterol	Proventil, Ventolin, AccuNeb	Inhaler, nebulizer
		Levalbuterol	Xopenex	Nebulizer
		Metaproterenol	Alupent	Inhaler
		Pirbuterol	MaxAir	Inhaler
		Ipratropium / Albuterol	Combivent	Inhaler
	Anticholinergics	Ipratropium	Atrovent	Inhaler
		Tiotropium	Spiriva	Inhaler
	Systemic Corticosteroids	Cortisone	Cortone	Pill
		Dexamethasone	Decadron	Pill
		Hydrocortisone	Cortef	Pill
		Methylprednisolone	Medrol	Pill
		Prednisolone	Orapred, Prelone	Syrup
		Prednisone	Various	Pill
		Triamcinolone	Aristocort	Pill
Long-Term Relief Medications (prevent attacks and control chronic symptoms)	Inhaled Corticosteroids	Beclomethasone	QVAR	Inhaler
		Budesonide	Pulmicort	Inhaler, nebulizer
		Budesonide / Formoterol	Symbicort	Inhaler
		Flunisolide	AeroBid	Inhaler
		Fluticasone	Flovent	Inhaler
		Fluticasone / Salmeterol	Advair	Inhaler
		Mometasone	Asmanex	Inhaler
		Triamcinolone	Azmacort	Inhaler
	Long-Acting Beta2-Agonists	Formoterol	Foradil	Inhaler
		Salmeterol	Serevent	Inhaler
	Anti-inflammatories	Cromolyn	Intal	Nebulizer
		Nedocromil	Tilade	Inhaler
	IgE-inhibitor	Omalizumab	Xolair	Injectable
	Leukotriene Modifiers	Montelukast	Singulair	Pill
		Zafirlukast	Accolate	Pill
		Zileuton	Zyflo	Pill
	Methylxanthine	Theophylline	Uniphyl, Quibron, Theo-24	Pill, syrup

Quick-Relief Medications

These medications quickly control acute asthma attacks.

Beta2-agonists do not reduce inflammation or airway responsiveness but serve as bronchodilators, relaxing and opening constricted airways during an acute asthma attack. They are used alone only for patients with mild and intermittent asthma. Patients with more severe cases should use them in combination with other drugs.

Specific short-acting beta2-agonists include:

Albuterol (Proventil, Ventolin), called salbutamol outside the U.S., is the standard short-acting beta2-agonist in America. Other similar beta2-agonists are isoproterenol (Isuprel, Norisodrine, Medihaler-Iso), metaproterenol (Alupent, Metaprel), pirbuterol (Maxair), terbutaline (Brethine, Brethaire, Bricanyl), and bitolterol (Tornalate). Isoetharine (Bronkometer, Bronkosol) is available in nebulizers.
Newer beta2-agonists, including levalbuterol (Xopenex), have more specific actions than the standard drugs. Studies have indicated that levalbuterol is as effective as albuterol with fewer side effects. The original formulation of Xopenex was administered with a nebulizer. A new metered-dose inhaler formulation became available in late 2005.

Short-acting bronchodilators are generally administered through inhalation and are effective for 3 - 6 hours. They relieve the symptoms of acute attacks, but they do not control the underlying inflammation. If asthma continues to worsen with the use of these drugs, patients should discuss corticosteroids or other drugs to treat underlying inflammation.

Side Effects of Beta2-Agonists. Side effects of all beta2-agonists include the following:

Anxiety
Tremor
Restlessness
Headache
Fast and irregular heartbeats. A doctor should be notified immediately if this side effect occurs, particularly in people with existing heart conditions. Such patients face an increased risk for sudden death from cardiac related causes. This risk is higher with oral or nebulized drugs, but there have also been reports of heart attacks and angina in some patients using inhaled beta2-agonists.

Beta2-agonists have serious interactions with certain other drugs, such as beta-blockers, and patients should tell the doctor about any other medications they are taking. Individuals with diabetes, existing heart disease, high blood pressure, hyperthyroidism, an enlarged prostate, or a history of seizures should take these drugs with caution.

Loss of Effectiveness and Overdose. There has been some concern that short-acting beta2-agonists become less effective when taken regularly over time, increasing the risk for overuse. Over time some patients may become tolerant to many effects of short-acting beta2-agonists. The degree to which this affects the airways is uncertain. In some studies, the duration of action has declined but the peak effect appears to be preserved, making these drugs still useful for acute attacks. Regular use of long-acting beta 2-agonists may reduce the effect of short-acting forms.

Patients who perceive beta2-agonists as being less effective may overuse them. Overdose can be serious and in rare cases even life-threatening, particularly in patients with heart disease.

Inhaled ipratropium bromide (Atrovent) acts as a bronchodilator over time. Ipratropium bromide alone is only modestly beneficial for acute asthma attacks. Moreover, the drug is not approved specifically for asthma. It may, however, have benefits in certain cases:

It may be useful for certain older patients with asthma who also have emphysema or chronic bronchitis.
A combination with a beta2-agonist might be helpful for patients who do not initially respond to treatment with a beta2-agonist alone.

Common oral corticosteroids include prednisone, prednisolone, methylprednisolone, and hydrocortisone. They very effectively reduce inflammation but are generally used only after hospitalization for an acute attack. In some severe cases, they may be used as maintenance.

Adverse effects of prolonged use of oral steroids include cataracts, glaucoma, osteoporosis, diabetes, fluid retention, susceptibility to infections, weight gain, hypertension, capillary fragility, acne, excess hair growth, wasting of the muscles, menstrual irregularities, irritability, insomnia, and psychosis. Osteoporosis is a common and particularly severe long-term side effect of prolonged steroid use. Medications that can prevent osteoporosis include calcium supplements, parathyroid hormone, bisphosphonates, or hormone replacement therapy in post-menopausal women.

Osteoporosis is a condition characterized by progressive loss of bone density, thinning of bone tissue, and increased vulnerability to fractures. Osteoporosis may result from disease, dietary or hormonal deficiency or advanced age. Regular exercise and vitamin and mineral supplements can reduce and even reverse loss of bone density.

Long-term use of oral steroid medications suppresses secretion of natural steroid hormones by the adrenal glands. After withdrawal from these drugs, this so-called adrenal suppression persists, and it can take the body a while (sometimes up to a year) to regain its ability to produce natural steroids again. There have been a few cases of severe adrenal insufficiency that occurred when switching from oral to inhaled steroids, which, in rare cases, has resulted in death.

No one should stop taking any steroids without consulting a doctor first. If the doctor orders steroids withdrawn, regular follow-up monitoring is necessary. Patients should discuss with their doctor measures for preventing adrenal insufficiency during withdrawal, particularly during stressful times when the risk increases.

Long-Term Relief Medications

These medications are taken on a regular basis to prevent asthma attacks and control chronic symptoms.

Inhalation of corticosteroids makes it possible to provide effective local anti-inflammatory activity in the lungs with minimal systemic effects. (By contrast, steroids taken by mouth have considerable side effects throughout the body.) Inhaled corticosteroids are recommended as the primary therapy under the following circumstances:

For any asthmatic condition more serious than occasional episodes of mild asthma. (Low-doses of inhaled steroids may even be safe and effective for some people with mild asthma, particularly those who find themselves using beta2-agonists daily.)
When treatment with bronchodilators is not effective.

Examples of inhaled corticosteroids:

The most recent generation of inhaled steroids include fluticasone (Flovent), budesonide (Pulmicort), triamcinolone (Azmacort and others), and flunisolide (AeroBid). In general, these newer steroids are more powerful than the older generation of inhaled drugs. These steroids are sometimes combined with a long-acting beta2-agonist in a single inhaler.
The FDA approved a new inhaled corticosteroid, mometasone furoate (Asmanex) in 2005.
The older corticosteroid inhalants are beclomethasone (Beclovent, Vanceril) and dexamethasone (Decadron Phosphate Respihaler and others). They are less powerful than the newer steroids when delivered with standard inhalers. New inhaler systems include QVAR, which uses extra fine formulations of beclomethasone to allow deep delivery into the lungs. Such systems may prove to be as effective as the newer, more potent steroids. Beclomethasone is believed to be safe during pregnancy.
Inhalers that combine both long-acting beta2-agonists and corticosteroids are also available. These include Symbicort (budesonide/formoterol), which in 2006 was approved for patients ages 12 years and older.

Traditionally, patients have been advised to take corticosteroids on a daily basis. However, a 2005 study suggested that intermittent corticosteroid therapy may be appropriate for some patients with mild persistent asthma. In the Improving Asthma Control Trial (IMPACT), researchers found that patients with mild persistent asthma who used an inhaled corticosteroid (budesonide) on an as-needed basis to control acute symptoms had similar lung function and quality of life outcomes as patients who used the drug daily. The researchers emphasize that patients with severe asthma should adhere to a daily dosage schedule, and that all patients with asthma should consult with their doctor to discuss any changes in medication regimen.

Optimal timing of the dose is important and may vary depending on the medication. Most of the newer inhaled steroids and even some older ones are now available as a single daily dose.

Inhaled steroids are generally considered safe and effective and only rarely cause any of the more serious side effects reported with prolonged use of oral steroids. Side effects of inhaled steroids are the following:

The most common side effects are throat irritation, hoarseness, and dry mouth. These effects can be minimized or prevented by using a spacer device and rinsing the mouth after each treatment.
Rashes, wheezing, facial swelling (edema), fungal infections (thrush) in the mouth and throat, and bruising are also possible but not common with inhalators.
A 2001 study reported a higher risk for cataracts in patients over age 40. (No higher risk was observed in younger people.)
Some studies report a higher risk for bone loss in patients who take inhaled steroids regularly, a side effect which is known to occur with oral steroids. A number of bone-preserving medications are now available that might safely offset this effect.
There is some concern that the more potent drugs, particularly fluticasone, suppress the adrenal system (which secretes natural steroids) to a greater degree than other steroid inhalants. (This is a serious side effect of oral steroids.)

Long-acting beta2-agonists are used in combination with inhaled corticosteroids for treating patients with moderate-to-severe asthma. These drugs include salmeterol (Serevent Diskus) and formoterol (Foradil Aerolizer). Combination single inhalers are available. One combines salmeterol and the corticosteroid fluticasone (Advair Diskus), and another combines formoterol and the corticosteroid budesonide (Symbicort).

Long-acting beta2-agonists are used for preventing an asthma attack (not for treating attack symptoms). The effects of one dose of a long-acting beta2-agonist last for about 12 hours, so these medicines are particularly effective during the night. These drugs also may be used for prevention of exercise-induced asthma in people and to protect against aspirin-induced asthma.

However, research indicates that long-acting beta2-agonists can worsen asthma by increasing symptom severity. These drugs may also increase the risk for asthma-related deaths. Experts are still trying to determine when long-acting beta2-agonists should be added to an asthma treatment plan. If your symptoms do not improve or if symptoms worsen with this type of drug, your doctor will recommend discontinuing it. Do not, however, stop taking this drug or other asthma medications without first talking with your doctor.

Side Effects. Side effects of long-acting beta2-agonists are similar to the short-acting drugs.

Specific Warning on Salmeterol and Formoterol. In 2003, a "black box" warning was added to product packaging for drugs that contain salmeterol, including Serevent Diskus, and Advair Diskus. The warning was based on a study that demonstrated more serious and even fatal asthma episodes in patients who used the drug than in patients who used a placebo. The risk for serious asthma episodes with salmeterol appears to be highest in African Americans and elderly patients with severe asthma.

In 2006, the FDA updated the warning to include formoterol (Foradil Aerolizer). Warnings for salmeterol and formoterol products emphasize that these medicines can increase the risk of severe asthma episodes. If these episodes occur, they can be fatal. Long-acting beta2-agonists require up to 20 minutes to achieve effectiveness, and there is a danger of overdose if a patient is not aware of this delay and takes additional doses to achieve faster relief. The FDA recommends that patients:

Use long-acting beta2-agonists only if other medicines (such as steroids) have not helped control asthma.
Use a short-acting bronchodilator, not a long-acting beta2-agonist, to treat sudden wheezing.
Do not use long-acting beta2-agonists to treat wheezing that is getting worse. Call your doctor if this situation occurs.
Do not stop using any asthma medicines without first talking to your doctor.

Cromolyn sodium (Intal) is both an anti-inflammatory drug and has antihistamine properties that block asthma triggers such as allergens, cold, or exercise. Nedocromil (Tilade) is similar to cromolyn. A cromolyn nasal spray called NasalCrom has been approved for over-the-counter purchase, but only to relieve nasal congestion caused by allergies. Patients should not use it for self-medication without the advice of a doctor.

Candidates. Cromolyn is often used in children with allergic asthma, but it has also been an important treatment for exercise-induced asthma (EIA) in all age groups, for pregnant women, and possibly for preventing allergic asthma in adults as well as children. Both cromolyn and nedocromil appear to be useful for patients with aspirin-induced asthma. These drugs do not effectively treat asthma once an attack is underway. They also have very little long-term benefits on lung function compared to inhaled corticosteroids.

Leukotriene-antagonists include zafirlukast (Accolate), montelukast (Singulair), zileuton (Ziflo), and pranlukast (Ultair, Onon). These drugs are proving to be effective for long-term prevention of asthma, including exercise-induced asthma and aspirin (or NSAID)-induced asthma. Most studies to date still report better success with inhaled corticosteroids than with the leukotriene-antagonists. Their anti-inflammatory actions are different from those of steroids, however, and combinations of the two drugs are being tried. A 2002 analysis of 13 studies, however, reported only modest benefits when anti-leukotrienes were added to corticosteroids. The combination did improve asthma control in some of the studies, but they did not reduce corticosteroid use. (In all but one of these studies the subjects were adults.)

Of some concern are reports of Churg-Strauss syndrome in a few people taking zafirlukast or montelukast. Churg-Strauss syndrome is very rare, but it causes blood vessel inflammation in the lungs and can be life threatening. Oral steroids quickly resolve the problem. Usually the syndrome has occurred in patients who were tapering off steroids and changing over to the leukotrienes-antagonists. Some experts believe that, in such cases, the steroids may simply have masked the presence of the disorder, which then developed when the steroid drugs were withdrawn. Symptoms include severe sinusitis, flu-like symptoms, rash, and numbness in the hands and feet.

Theophylline. Theophylline (Theo-Dur, Theolair, Slo-Phyllin, Slo-bid, Constant-T, Respbid) relaxes the muscles around the bronchioles and also stimulates breathing. One study reported that it may also have anti-inflammatory qualities even in low doses. Available in tablet, liquid, and injectable forms, some theophylline sustained-release tablets and capsules have a long duration of action and can, therefore, be taken once or twice a day with good results.

If theophylline is not taken exactly as prescribed, an overdose can easily occur. Toxicity can cause nausea, vomiting, headache, insomnia, and, in rare cases, disturbances in heart rhythm and convulsions. Contact a doctor immediately if any of these side effects occur.

The risks for these adverse effects are small if the drug is taken exactly as prescribed, but the following precautions should be noted:

Chronic smokers metabolize theophylline much more quickly and require higher doses of the drug than nonsmokers; prolonged-release versions are helpful for such people.
Too much caffeine can increase the concentration of this drug and the amount of time it stays in the body.
Theophylline also interacts with many other drugs that are taken for other common medical conditions, including asthma. Exercise caution when using beta2-agonists and theophylline together.
No one with a peptic ulcer should take theophylline. The elderly and anyone with heart disease, liver disease, hypertension, seizure disorders, or heart failure, should take theophylline with caution. Of special note, people with heart conditions who take theophylline orally face an increased risk for sudden death from heart-related causes.

However, about 1 in 1,000 patients who take omalizumab develop anaphylaxis (a life-threatening allergic reaction). In 2007 the FDA requested the manufacturers of omalizumab put a “boxed warning” on the medicine’s label emphasizing the drug’s risk for anaphylaxis. The boxed warning notes that patients can develop anaphylaxis after any dose of omalizumab, even if they had no reaction to a first dose. Anaphylaxis may occur up to 24 hours after the dose is given.

The FDA recommends that health care providers observe patients for at least 2 hours after an injection. Patients should also carry emergency self-treatment for anaphylaxis (such as an Epi-Pen) and know how to administer it. With an Epi-Pen, or similar auto-injector device, patients can quickly give themselves a life-saving dose of epinephrine.

Anaphylaxis symptoms include:

Difficulty breathing
Chest tightness
Dizziness
Fainting
Itching and hives
Swelling of the mouth and throat

Other Treatments

Various drugs are being investigated for asthma treatment. Some of these drugs have anti-inflammatory effects, which may help reduce dependence on corticosteroids. For example, etanercept (Enbrel), which blocks the inflammatory protein called tumor necrosis factor alpha, is being investigated for patients whose asthma has not responded to other drugs. The humanized monoclonal antibody daclizumab has also improved asthma control in patients with treatment-resistant asthma, as well as patients with moderate to severe chronic persistent asthma. Certain antibiotics, such as clarithromycin (Biaxin), may improve lung function in patients with asthma who show evidence of infection with the bacterial organisms Mycoplasma or Chlamydiapneumoniae. Dapsone, a drug known as a sulfone, is also under investigation.

Alternative therapies are being widely used by children, adolescents, and adults with asthma. In one study, nearly half of asthma or allergy sufferers resorted to alternative treatments. To date, however, evidence does not support any value from most alternative therapies, including high-dose vitamins, urine injections, homeopathic remedies, and most herbal remedies.

Relaxation and Stress-Reduction Techniques. Patients report benefits from many stress reduction techniques, such as acupuncture, hypnosis, breathing relaxation techniques, massage therapy, and meditation practices.

Acupuncture, hypnosis and biofeedback are all alternative ways to control pain. Acupuncture involves the insertion of tiny sterile needles, slightly thicker than a human hair, at specific points on the body.

The Buteyko Breathing Method. The Buteyko breathing method is an experimental approach designed to increase levels of carbon dioxide in the body. To do this, patients are trained to reduce their volume of breath and to avoid hyperventilation (over-breathing). Some studies have reported that patients using this method reduce their use of medications and improve their quality of life. The system originated in Australia and is not yet widely available in the U.S.

Probiotics. Probiotics are beneficial bacteria that may help protect against allergies and asthma. Antibiotic over-use and modern hygiene may specifically be reducing these helpful organisms. Probiotics can be obtained in active yogurt cultures and in supplements, which are being studied for protection.

Herbal Remedies. There have been few rigorous studies on herbal remedies for asthma. Butterbur (also known as Petasites hybridus, butter dock, blatterdock, bog rhubarb, and exwort) is one traditional herbal remedy used for treating seasonal allergies and asthma. In a 2002 study, it appeared as effective and less sedating than a commonly prescribed antihistamine for treating seasonal allergies over a 2-week period, but there has been little research on its effect on asthma.

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 a number of 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.

Managing Asthma

Avoidance or control of the triggers that lead to asthma attacks is as much a priority as treatment of the disease.

Controlling Pets. Patients who already have pets and are not allergic to them probably have a low risk for developing allergies. If pets trigger asthma, however, they should be kept outside. If this isn't possible, they should at least be confined to carpet-free areas outside the bedroom. Cats harbor significant allergens, which can even be carried on clothing; dogs usually present fewer problems. Washing animals once a week can reduce allergens. Dry shampoos, such as Allerpet, are now available for both cats and dogs that remove allergens from skin and fur and are easier to administer than wet shampoos.

Controlling for Dust. Spray furniture polish is very effective for reducing both dust and allergens. Air cleaners, filters for air conditioners, and vacuum cleaners with High Efficiency Particle Arresting (HEPA) filters can help remove particles and small allergens found indoors. Neither vacuuming nor the use of anti-mite carpet shampoo, however, is effective in removing mites in house dust. In fact, vacuuming stirs up both mites and cat allergens. If possible, avoid carpets and rugs.

A HEPA (High Efficiency Particle Arresting) filter can remove the majority of harmful particles, including mold spores, dust, dust mites, pet dander and other irritating allergens from the air. Along with other methods to reduce allergens, such as frequent dusting, the use of a HEPA filtration system can be a helpful aid in controlling the amount of allergens circulating in the air. HEPA filters can be found in most air purifiers, which are usually small and portable.

Bedding and Curtains. Many experts recommend reducing exposure to dust mites by enclosing mattresses and pillows in semipermeable coverings. (Vinyl mattress covers limit airflow and may also worsen, or even cause, asthma in children. Synthetic pillows may pose a significantly higher risk for severe asthma attacks in children than feather or no pillows.) However, several 2005 studies suggested that such covers do not prevent asthma or allergies. Replace curtains with shades or blinds, and wash bedding using the highest temperature setting.

Reducing Humidity in the House. Although warm, moist air from vaporizers can greatly ease and moderate asthma attacks, living in a damp house is counterproductive. Dust mites thrive in humidity and damp houses increase the risk for mold, so on-going humidifiers can be unuseful. If they are used, humidity levels should not exceed 40% and they should be cleaned daily with a vinegar solution.

Gas Stoves, Kerosene, and Cooking. People with asthma should choose electric ovens rather than gas, which release nitrogen dioxide, a substance that can aggravate asthma symptoms. Even smoky cooking can worsen asthma. Kerosene (used in space heaters and lamps) may also produce allergic reactions.

Exterminating Pests (Cockroaches and Mice). Use a professional exterminator to eliminate cockroaches. (One study reported that ridding a home of cockroaches and cleaning the house using standard housecleaning techniques failed to eliminate the cockroach allergens themselves.) Exterminate mice and attempt to remove all dust, which might contain mouse urine and dander.

Avoiding Smoking and Cigarette Smoke. Cigarette smoke can accelerate the decline in lung function related to asthma. Even exposure to secondhand smoke can double the risk of asthma-related emergency room visits. In one study, it was the most frequently cited trigger of asthma symptoms. Everyone should quit smoking and encourage others around them to quit. [For help in quitting, see In-Depth Report # 41: Smoking.]

Click the icon to see an image of common asthma triggers.

Avoiding Outdoor Allergens. The following are some recommendations for avoiding allergens outside:

Avoid scheduling camping and hiking trips during times of high pollen count (generally, May and June for grass pollen and mid-August to October for ragweed).
Avoid strenuous activity when ozone levels are highest, which usually occur in early afternoon, particularly on hot hazy summer days. Levels are lowest in early morning and at dusk.
Asthma attacks are often higher during thunderstorms. It is not clear why. Some evidence points to a build-up of ozone that accompanies such storms. One study suggested that changing airflow patterns bring a sudden downdraft of air containing concentrations of pollens, small particles and allergens.
Patients who are allergic to mold should avoid barns, hay, raking leaves, and mowing grass. Exposure to automobile fumes may worsen asthma. Fungi in car air conditioners can also be a problem.

Click the icon to see an image of fungus.

Reducing Exposure to Air Pollution. A number of studies have linked air pollution to asthma. An important 2000 study found a strong association between higher mortality rates from heart and lung diseases and high levels of specific pollutants (ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide). Some experts point out that asthma rates in North America have increased over recent years while the prevalence of many common air pollutants have declined. Nevertheless, evidence strongly suggests that air pollution can worsen existing asthma and patients should take precautions if they are exposed to polluted air.

A number of studies have estimated that between 2 - 26% of adult-asthma cases are related to work history. Some experts encourage doctors to suspect occupational factors in all cases of adult-onset asthma. Although workers who have allergies, who smoke, or both are at higher risk than others, any worker exposed to occupational triggers may be at risk for asthma.

Work-related asthma is one of two types:

Work-aggravated asthma, in which existing asthma symptoms are triggered by irritants at the workplace
Occupational asthma, which is new-onset asthma strongly associated with conditions at work

Occupational asthma is further categorized as:

Nonlatent (symptoms occur right after exposure to an irritant, usually high concentrations of gas, fumes, dust, or chemicals)
Latent (symptoms develop after prolonged exposure to substances in the workplace)

Occupational Triggers. Over 250 substances have been identified as potential occupational triggers of asthma, and the list is growing. A few of these chemicals and substances include:

Isocyanates used in the manufacture of polyurethane, paints, steel, and electronics
Trimellitic anhydrides (TMA) used in many plastics and epoxies
Western red cedar, oak, redwood, and mahogany
Metal salts (platinum, nickel, and chrome) and metal working fluids
Vegetable dusts (soybeans, grains, flour, cotton, and gums)
Biologic organisms (Bacillus subtilis, pancreatic enzymes)
Xylanase used in the baking industry
Pharmaceuticals (penicillin, phenylglycine acid chloride)
Glutaraldehyde used to sterilize medical equipment
Red dye made from the cochineal insect
Diacetyl, the main chemical in artificial butter flavoring used in popcorn

Workers in these industries and others, including farmers, hairdressers, and those who work in the garment industries are at risk for asthma.

Preventing Occupational Asthma. In people whose asthma is caused by workplace conditions, improved ventilation or face masks may help.

Sometimes, however, even low levels of chemical substances can trigger an asthma attack. In such cases, leaving the job is the only way to prevent the condition from getting worse. Because such a step can be emotionally and financially threatening, workers should be sure that occupational substances are the cause of the asthma by having a complete check-up by a lung specialist.

If the diagnosis of occupational asthma is certain, patients should obtain advice on available compensation plans for disability. The effects of workplace asthma can be permanent. However, in one study, 70% of people with asthma experienced significant improvement in symptoms after leaving the job.

Immunotherapy ("allergy shots") may help reduce asthma symptoms, and the use of asthma medications, in patients with known allergies. They may also help prevent the development of asthma in children with allergies. Immunotherapy poses some risk for severe allergic reactions, however, especially for children with poorly controlled asthma.

[See In-Depth Report #77: Allergic rhinitis; and Report #5: Asthma in children and adolescents.]

Preventing and Treating Respiratory Infections. Respiratory infections, including the common cold, can act with allergies to worsen asthma. People with asthma should try to minimize their risk for respiratory tract infections. Washing hands is a very simple but effective preventive measure.

Patients with asthma should ask their doctors about the flu vaccine and also whether they should receive the vaccination against pneumococcal pneumonia.

Zanamivir, a new drug used for treating influenza, is considered safe for patients with asthma 12 years of age or older. In one study, patients with asthma who were treated with zanamivir experienced fewer flu symptoms and had improved lung function. [See In-Depth Report #94: Colds and influenza.]

Managing Hormonal-Related Asthma. Women who suspect that menstrual-related changes may influence asthma severity should keep a diary recording their menstrual dates and times of asthma attacks. In some cases, adjusting medications in anticipation of menstruation may help prevent attacks. Some small studies have suggested that hormonal drugs called gonadotropin-releasing hormone (GnRH) analogues may help women with severe premenstrual asthma. Such drugs reduce or suppress estrogen levels, however, and can have severe side effects. More research is needed to determine if the disadvantages outweigh the benefits.

Weight Loss. People who have asthma and who are overweight may help reduce asthma symptoms with weight loss.

Vitamin D. There may be an association between a lack of vitamin D and asthma. Some research suggests that children are less likely to develop asthma at a young age if their mothers consume a high intake of vitamin D during pregnancy. Vitamin D is available from dietary sources or vitamin supplements.

Fish Oil. Omega-3 fatty acids, found in cold water oily fish and in supplements (preferably DHA-EPA, which are the important compounds in fish oil) have anti-inflammatory effects. Some evidence suggests they may be helpful for people with asthma, although it is weak.

Caffeine. Caffeine has properties that are similar to theophylline, a drug used to treat asthma. A major analysis of studies reported that caffeine improved lung function for up to 4 hours after consumption. (People who are going to have their lung function tested should avoid drinking coffee, tea, or other caffeinated beverages for at least 4 hours beforehand.)

Alcohol. In adults, some research suggests that alcohol intake may influence allergy severity. One study found that as little as one drink a day is enough to worsen dust mite allergies.

Role of Food Allergies. Although 67% of people with asthma believe their symptoms are aggravated by food allergies, studies indicate that this belief may be true in only 5% of cases. The primary suspects are monosodium glutamate, or MSG (found in some canned soups, cheese, and certain vegetables), and sulfites (preservatives in wine and foods that include processed frozen potatoes and tuna). Contrary to what many people believe, dairy products do not appear to worsen asthma symptoms in people who are not already allergic to them.

Asthma is no reason to avoid exercise. Historically, about 10% of Olympic athletes have asthma. Some studies indicate that long-term exercise even helps control asthma and reduce hospitalization. Patients should consult their doctors before embarking on any exercise program, however. Uncontrolled asthma can be dangerous and, in rare cases, can be fatal for athletes, even some with mild asthma. Use of the inhaler is extremely important.

People who enjoy running should probably choose an indoor track to avoid pollutants. Swimming is excellent for people with asthma. Yoga practice, which uses both stretching, breathing, and meditation techniques, may have particular benefits. One study reported that two-thirds of patients who practiced yoga regularly were able to reduce or stop taking their asthma medications.

Exercise-induced asthma is a limited condition that has specific recommendations.

People with asthma have no higher rate of anxiety or depression than the general population. However, such emotions interact with the effects of asthma and its treatments in important ways:

Negative emotions can discourage compliance with medication and the ability to cope
Poor control of asthma symptoms, in turn, increases the risk for negative emotions
Stress and depression have been associated with more severe symptoms and even an increased risk of fatal asthma attacks

Some evidence suggests that stress reduction techniques, a positive attitude and relaxation techniques can be very helpful in the long-term management of asthma. [See In-Depth Report #31: Stress.]

Resources

www.lungusa.org -- The American Lung Association
www.acaai.org -- American College of Allergy, Asthma & Immunology
www.aaaai.org -- American Academy of Allergy, Asthma & Immunology
www.nhlbi.nih.gov -- National Heart, Lung, and Blood Institute
http://asthma.nationaljewish.org -- National Jewish Medical and Research Center
www.aafa.org -- Asthma and Allergy Foundation of America
www.aarc.org -- American Association for Respiratory Care

References

Glassroth J. The role of long-acting ß-agonists in the management of asthma: Analysis, meta-analysis, and more analysis. Ann Intern Med 2006 Jun 20; 144:936-7.

Kiljander TO, Harding SM, Field SK, Stein MR, Nelson HS, Ekelund J, et al. Effects of esomeprazole 40 mg twice daily on asthma: a randomized placebo-controlled trial. Am J Respir Crit Care Med. 2006 May 15;173(10):1091-7.

Review Date:
3/27/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

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