The Principles of Diets

Many people find the quick, easy weight loss promised by diets tempting. However, most popular diets do not provide lasting results, even if people temporarily lose weight while they are following the diet. Don't be misled by advertising claims; there are no tricks or shortcuts to losing weight. Instead, lasting weight loss requires you to change your eating habits permanently.

Dieting Basics

• To lose weight, you must expend more calories than you take in. You can achieve this by eating fewer calories than you expend, by increasing your caloric expenditure through exercise or by combining the two. Some diets claim to help you lose weight by including "calorie-burning" foods or by instructing you to eat certain food groups at certain times, but these gimmicks are not scientifically sound.

Diet Myths

• Advertisements for diets often give incorrect information about weight loss. For example, some diets claim that certain foods, such as celery or cabbage soup, help you burn calories. No type of food burns fat or calories. Other diets suggest that carbohydrates and starches cause weight gain -- but high-protein diets may raise your risk for heart disease, gout and constipation. Some people also incorrectly believe that eating late at night causes weight gain or that skipping meals is an effective weight-loss strategy.

Pitfalls of Popular Diets

• Many popular diets don't provide enough nutrients. For example, women may not get enough protein while eating a dairy-free diet. Some diets also restrict liquids, which can create the illusion of weight loss through dehydration. Many diets provide little variety, which causes people to become bored more quickly. Diets that require special products, such as liquid shake diets, can be very expensive. Finally, dieting may affect your attitude toward food in negative ways; for example, you may categorize certain foods as "bad" or try to ignore physiological signals of hunger and fullness.

Weight-Loss Tips

• If you want to lose weight, plan to do so gradually and steadily, and prepare to make lifelong changes in your diet and exercise habits. Most people can reduce their caloric intake by 500 to 1,000 calories per day to lose 1 to 2 lb. per week, according to the Centers for Disease Control and Prevention. Eat breakfast; eat small snacks regularly; and stop eating at meals once you feel full. In addition, try to exercise most days of the week.

Warning

• Talk to your doctor before taking supplements intended to help you lose weight, even if they are labeled "natural" or "herbal." These products have not been tested for safety or efficacy. For example, the herbal weight-loss supplement ephedra caused several deaths before it was banned by the Food and Drug Administration. Diet supplements may also cause unpleasant side effects, such as irritability and insomnia.