Calories count despite debate on best weight-loss plans.(Clinical Rounds)

NEW ORLEANS -- Calorie restriction, rather than the carbohydrate or fat content or the glycemic index of the diet, is of great importance in losing weight, Ernst J. Schaefer, M.D., said at the annual scientific sessions of the American Heart Association.

"There's a lot of controversy out there about the kind of diet that one should eat for weight loss and whether calories from one food are different than calories from another food. Everybody's always looking for some sort of a magic bullet. But our controlled feeding study clearly indicates that a fat calorie and a carbohydrate calorie and a protein calorie are equivalent when it comes to weight loss--or weight gain," said Dr. Schaefer, professor of nutrition science and policy at Tufts University, Boston.

He presented a National Institutes of Health-sponsored study designed to test the hypothesis that a low-fat and/or low-glycemic-index diet would have more favorable effects on weight loss, cardiovascular risk profile, and glucose metabolism than a moderate-fat and/or high-glycemic-index diet.

For the most part, the hypothesis was not borne out, said Dr. Schaefer, also chief of the lipid metabolism laboratory and senior scientist at the Jean Mayer USDA Human Nutrition Research Center on Aging.

The study involved 80 obese men and women with a mean body mass index of 34 kg/[m.sup.2]. All were placed for 5 weeks on an average American diet at about 35 calories/kg per day. They were then randomized to one of four weight-loss diets. One test diet contained 15% of calories as fat, another had 30% calories as fat, a third had a glycemic index of 85, and another had a glycemic index of 45.

All four diets were heart healthy, with 15% of calories as protein, 5% ...