Obesity (Overweight)

Being overweight is the most prevalent nutrition-related health problem in the United States, affecting about half of all adults. Of these, 30 percent are obese, defined as being 20 percent or more above desirable weight. In addition to creating psychological and self-image problems, obesity increases the risk of some of our most lethal disorders, including diabetes and heart disease, and has been linked to an increased risk of cancers of the breast, uterus, ovaries, colon, prostate gland, and gallbladder. Excess weight also contributes to arthritis, back and foot pain, and respiratory disorders. In women, obesity can lead to menstrual irregularity and fertility problems.

The more you weigh, the greater the danger. One long-term study of several thousand men found that every pound over their ideal weight increased their mortality rate by 1 percent between ages 30 and 49, and 2 percent per pound among those 50 to 62.

Until recently, being overweight was thought to be a simple matter of consuming more calories than the body burned during daily activities. We now know that weight problems are more complex, involving heredity, hormones, psychological makeup, and ethnic and cultural background, among other factors. Heredity is especially important; for example, a study of identical twins who were raised by different families revealed that they tended to develop about the same weight by adulthood, regardless of their eating habits and other environmental factors.

Recognizing that the problem of obesity goes beyond will power, it is not surprising that about 90 percent of dieters regain within five years all or most of any weight lost. However, this does not mean that attempts at weight loss are hopeless. Long-term weight-control programs that take a slow but steady approach are most likely to bring lasting success. Even if people do not achieve their ideal weight, modest reductions may still lower their risks of some disorders, such as diabetes.

Diagnostic Tests and Procedures

A certain body weight alone does not necessarily indicate a problem; what's important is whether or not you have too much body fat. An objective look in the mirror can be more telling than a scale -- if you look fat and flabby, you probably are overweight. In contrast, if you are big boned and muscular, your weight may exceed what is considered ideal, but you will still look trim and fit, because muscle and bone weigh more than fat.

To determine if you have too much body fat, a doctor may use calipers, instruments that measure the thickness of a skin fold -- the amount of skin and underlying fatty tissue that you can pinch together. About 50 percent of body fat lies just below the skin; thus skin folds more than an inch thick on your underarm or the area just above your hip bone indicate excess body fat.

An even more accurate measurement of body fat is obtained by underwater weighing. You are weighed on land, and again while submerged in water. A formula based on these two weights gives the percentage of body fat.

Additional tests that may pinpoint the cause of excess weight include blood, urine, and hormone studies. A doctor will also want to review your eating habits and activity levels, which are important not only in finding the cause of weight gain, but also for devising a regimen to lose the excess pounds and then keep them off.

Medical Treatments

Many weight specialists now consider obesity a chronic disease that calls for lifelong treatment with a combination of lifestyle changes, alternative therapies, and perhaps drugs. Indeed, some doctors say that treating obesity without drugs will some day be viewed as archaic, like telling a person to control hypertension simply by cutting down on salt and staying in bed.

Mild obesity -- when weight is 20 to 40 percent above what is considered ideal -- usually can be self-treated, perhaps with the assistance of nutrition and exercise professionals.

Moderate obesity, defined as weight 40 to 100 percent above normal, is likely to require treatment with a medication to suppress appetite, a diet planned by a dietitian or nutritionist, and possibly behavior modification, assisted by a psychiatrist or psychologist.

Severe obesity of more than 100 percent above normal may require surgical intervention in addition to drugs, diet, and behavior modification.

Drug Therapy. Historically, most doctors viewed diet pills, or anorectics, as unnecessary and potentially addictive crutches. This attitude changed with the introduction of safer drugs that can be used long-term. But even proponents of these drugs stress that relying on pills alone does not break bad eating habits or teach new ones. Thus, most physicians prescribe diet pills as a temporary aid to promote weight loss while the person adopts new eating and exercise habits.

The major function of diet pills is to suppress appetite and, in some cases, to reduce cravings for certain high-calorie foods. For example, some people turn to sweets when they feel depressed or tense. Simple carbohydrates raise levels of tryptophan (a natural amino acid) in the bloodstream; the tryptophan, in turn, increases the production of serotonin, a brain chemical that improves mood. Thus, people who habitually turn to carbohydrates io improve their moods may have trouble shedding pounds without the aid of diet pills. Most diet pills have similar side effects, which may include nervousness, high blood pressure, palpitations, headaches, dizziness, insomnia, mood swings, tremor, dry mouth, diarrhea, constipation, itching, and rashes.

It is necessary to abstain from alcohol while taking any type of diet pill, and restrict caffeine, which can add to the nervousness. Also, these drugs cannot be prescribed for more than 12 consecutive weeks because they are classified as potentially addictive.

Diet pills include the following:

• Stimulants, such as dextroamphetamines, which are the oldest types of diet pills and the most addictive; their use is now discouraged.
• Amphetamines, commonly called uppers, work by suppressing the appetite. They may also speed up metabolism, but this is unclear. After a few weeks, however, a tolerance for the drugs develops, thus decreasing their benefit and raising the risk of addiction should the dosage be increased.
• Fenfluramine (flondimin), a drug that is chemically similar to amphetamines but with fewer stimulant and dependency problems. It suppresses appetite by raising the level of serotonin in the brain. It also increases the body's utilization of glucose.
• Pientcrmine (Faslin and Adipex-P), also chemically similar to amphetamines. It carries somewhat less risk of dependency, however.
• Fluoxetine (Prozac), one of the newest diet drugs; it is better known as an antidepressant. Prozac effectively increases levels of serotonin in the brain, where it helps curb appetite and elevate mood.
• Phenylpropanolamine (Dexairim and Control), an over-the-counter drug that shares many of the stimulatory effects of amphetamines. It is also used in medications designed to relieve allergies and bronchial asthma.

Surgical Treatment. Several operations have been developed for treating life-threatening severe obesity. Some involve reducing the size of the stomach so that a person feels full after eating only small amounts of food. Others involve removing parts of the small intestine, thus reducing the absorption of nutrients. People who have such operations usually show a rapid weight loss, which then tapers off after a few years. These major surgical techniques are recommended only for people with severe weight problems who have failed to lose weight by all other means. Afterwards, patients must undergo frequent checkups because of an increased risk of metabolic disorders and other serious health problems that can result from the operation.

Alternative Therapies

Many of the alternative therapies promoted for weight loss either do not work or are potentially dangerous. Liquid protein diets, for example, have been linked to fatal cardiac arrythmias that develop when the body metabolizes lean tissue, including heart muscle. Ephedra, or mahuang, a popular herbal remedy, raises blood pressure and can cause stroke and nerve damage.

Exercise Therapy. All successful weight-loss programs include exercise to help regulate appetite and stabilize the metabolic rate. Walking one mile at any pace burns up about 100 calories. It's best to start by walking a half-mile in 15 minutes every day, and with time, build up the pace and increase the distance to 3 miles in 45 minutes. Taking a brisk walk before a meal has the added benefit of curbing appetite.

A markedly overweight person should consult a doctor before under-taking an exercise program. If there is no heart disease or other problem that precludes vigorous exercise, a trained exercise physiologist can help plan a progressive conditioning regimen to burn calories and build muscle and strength. Initially, exercising in water may be recommended because it is easier on weight-bearing joints than other activities. As weight is lost, walking and other low-impact aerobic exercises can be added to the plan.

Nutrition Therapy. This remains the mainstay of all weight-loss programs. A nutritionist or registered dietitian can help plan a healthy diet that allows a gradual weight loss while adopting new eating habits. Any weight-loss diet should include a variety of foods and provide at least 1,000 calories a day. Even then, a multiple vitamin may be needed to ensure adequate nutrition.

Crash diets should be avoided. Any eating plan that restricts calories will result in weight loss, but a rapid shedding of pounds is self-defeating. When calories are overly restricted, your body lowers its metabolic rate to conserve energy. Even after you have achieved your weight goal, your body will continue to run at a slower pace, meaning that it needs fewer calories than normal. So just to avoid regaining weight, you must continue to restrict calories.

Self-hypnosis and Visualization. These techniques can help prevent overeating. For example, if a person frequently turns to chocolate or some other high-calorie sweet, a hypnotist can implant a suggestion that makes such foods undesirable and foster a craving for a low-calorie substitute.

Self-Treatment

Before undertaking any significant changes in your eating or exercise habits, consult your doctor if you: Have any chronic health problem, such as diabetes, gallstones, glaucoma, depression, or heart, kidney, liver or thyroid disease. Are taking any sort of medication on a regular basis. Want to lose more than 15 pounds. Are under age 21 or over age 35. Are pregnant.

Your goal should be to lose two or three pounds a week, and then to maintain the loss. This means bringing about a permanent change in your eating and exercise habits. Start by keeping a careful food diary for at least two weeks. Be sure to write down everything you eat and drink immediately; it's difficult to reconstruct a days total intake if you wait until evening. Note what prompts you to eat; this helps identify habits that might need adjusting. If, for instance, you tend to nibble on whatever is handy while studying or watching TV, you should keep on hand low-calorie foods such as fat-free crackers, raw vegetables, or unbuttered popcorn, instead of potato chips and nuts.

Successful weight loss invariably requires some change in eating behavior. You may need to eat more slowly, or you might have to adopt new attitudes toward food. Joining a self-help group such as Weight Watchers or Over eaters Anonymous may provide the motivation you need. The following principles of good nutrition can also help.

Make breakfast and lunch your main meals, and end the day with a light dinner. This type of eating schedule provides the most calories when you are active, and prevents you from becoming overly hungry, which can lead to overeating and weight gain.

Reduce your intake of high-fat foods, such as cheese, cream, mayonnaise, luncheon meats, butter, ice cream, nuts, pies, and anything that is fried. Use low-fat or non-fat dairy products, lean cuts of meat, such as beef round, and reduced fat salad dressings. Grill, steam, roast, or broil foods, or saute them in a nonstick pan instead of frying. Remove the skin from poultry.

Increase your intake of complex carbohydrates, especially those that are high in fiber, such as vegetables and whole-grain breads and cereals. Avoid artificial sweeteners, which have been shown to stimulate appetite.

Take a fiber pill or guar, available in pill or powder form, with a glass of water about 30 minutes before eating to curb your appetite.

At meals, serve yourself moderate portions and don't take seconds, except of vegetables. If you feel deprived, serve your food on a smaller plate, which will make portions look bigger. For snacking between meals, keep on hand low-fat choices, such as hard pretzels, carrot sticks, rice or soda crackers, fruit, or non-fat yogurt. When eating out, order a low-fat main course that is broiled, steamed, or roasted, and ask that any sauce or butter be served on the side. Similarly, request that salad be served with the dressing in a separate container. Many ethnic foods, especially those that emphasize grains and vegetables, generally are good choices, but ask how they are prepared. Sauteed Chinese dishes -- commonly thought of as being low in calories -- have often been cooked with a large amount of oil. Similarly, even plain popcorn served in movie theaters usually contains oil.

Other Causes of Overweight

Unexplained weight gain may be caused by an underactive thyroid gland (hypothyroidism), depression, and conditions such as congestive heart failure, kidney failure, and cirrhosis of the liver that promote excess fluid retention. Long-term use of steroid drugs also causes weight gain.