Overweight is here - but it needn't be here to stay

By now almost everyone acknowledges two facts: The first is that Americans have a weight problem. By standard definitions (see lower box, page 19), one third of adults are overweight and another third are obese. The second fact is that overweight is an enormous burden on our health. It increases the risk of developing type 2 diabetes, high blood pressure, cardiovascular dis-ease, and certain cancers.

Tipping the energy balance Special diets and products have been promoted to help people shed pounds. Experts point out, however, that weight loss comes down to a simple formula: consuming fewer calories than we burn. Recently a group of Mayo Clinic doctors recommended that overweight people aim for a daily deficit of 500 calories, which can be expected to lead to a loss of about a pound a week. In principle, that can be achieved entirely by eating less (fewer calories consumed) or entirely by increasing activity (more calories burned). But in practice, these experts say, a meaningful loss can be sustained only by a combination of the two strategies.

Losing it through diet

Diet remains the cornerstone of weight loss, and many different diets—low-carb, high-protein, very-low-fat, and so on—have been introduced over the years. None, how-ever, appears to have a clear advantage over the others. After one year, people on a variety of diets have all lost about the same amount.

The most solid guideline for dieters is simply to reduce the amount of calories (energy) consumed. The Mayo Clinic doctors suggest that that can best be accom-plished by a combination of dietary changes.

Those changes aim to reduce calorie intake. The doctors recommend that a person

• cut back on total fat intake
• decrease portion size
• opt for foods that are less calorie-dense (more filling than fattening)
• eat more fruits and vegetables.

Getting active

The other side of the energy balance equation, of course, is physical activity. Most studies suggest that exercise contributes relatively little to losing weight, but it’s key to maintaining weight loss. The amount of time spent exercising is more important than the intensity of the exercise. Faithfully doing 30 to 60 minutes of exercise a day, 5 to 7 days per week, is essential to maintain weight loss for the long term. And beyond formal exercise, research has shown that simply being more active in everyday life—e.g., using the stairs rather than an elevator
and getting up to change TV channels rather than clicking a remote—burns considerable calories.

Making changes

Changing one’s habits and lifestyle to achieve a new weight is difficult. Finding the willpower is often a losing proposition. Behavioral psychologists suggest that people learn to avoid tempting foods or, when that's ?impossible, think of the consequences of indulging. Another tactic is to distract oneself with other activities. It’s also important to

• monitor your behavior, keeping track of what you eat and how much you exercise
• set achievable, short-term goals
• focus on successes and not be thrown by setbacks.

Get your family to support your goals. Professionals have a role to play too. For example, a dietitian can show you how to plan nutritious, low-cal meals. A trainer can create an exercise plan and provide ongoing motivation.

Medical and surgical options

Drugs have been shown to have limited effectiveness. Appetite suppressants provide only small, short-term weight loss. Orlistat (Xenical, alii), which prevents fat absorption, does help you to lose some weight, lower “bad” LDL cholesterol, and improves glucose tolerance. But the long-term safety of this and other weight-loss drugs is unknown. And when you stop taking them, weight is regained.

Bariatric surgery is reserved for extremely obese people and obese individuals with significant weight-related health problems. This approach appears to be the only one that consistently produces substantial weight loss in the long term.

From the Mayo Clinic Proceedings