WASHINGTON -- Most of the nation's estimated 25 million overweight citizens can and do lose weight -- but too many don't make the permanent lifestyle changes to keep it off, a panel of experts has concluded.
"These people are using a variety of strategies including diet, exercise and behavior modification. Unfortunately, most people who [lose weight these ways] regain their weight in one to three years," said Dr. Suzanne Fletcher, who headed a National Institutes of Health panel examining weight loss and control.
"The most important finding is how difficult it is to maintain weight loss," said Dr. Fletcher.
Many factors cause excess weight, including genetics, culture and psychological conditions, Dr. Fletcher said. No one really knows why some individuals successfully lose weight on their own, the panel concluded, or how effective commercial weight-loss programs may be for dieters.
"We just don't know what separates successful people who do it on their own -- those who clip diets from a magazine or from a brochure and succeeded. They obviously don't appear at our clinics. It may be that they get to it earlier so they don't have to make very many changes to make a difference in their weight," said Helen A. Guthrie, nutrition professor emeritus at Penn State University.
The panel developed its report after a three-day conference here of scientists specializing in nutrition, obesity, metabolism, exercise and other disciplines. The panel, all independent experts, reviewed the conferees' studies before giving their statement yesterday at a news conference.
The panel concluded a combination of dieting, exercise and behavior modification was the best way to lose weight and maintain the loss over a lifetime.
"Any program of which the primary goal is short term rapid or unsupervised weight loss or which relies on diet aids such as drinks, prepackaged foods or pharmacologic agents without an education in and eventual transition to a lasting pattern of healthful eating and activity has never been shown to be successful over the long term," the panel said.