SIMILAR WEIGHT-LOSS WITH LOW-CARBOHYDRATE OR HIGH-CARBOHYDRATE DIETS

The goal of this study was to evaluate the effect of diets that were e qually low in energy but widely different in relative amounts of fat a nd carbohydrate on body weight during a 6-wk period of hospitalization . Consequently, 43 adult, obese persons were randomly assigned to rece ive diets containing 4.2 MJ/d (1000 kcal/d) composed of either 32% pro tein, 15% carbohydrate, and 53% fat, or 29% protein, 45% carbohydrate, and 26% fat. There was no significant difference in the amount of wei ght loss in response to diets containing either 15% (8.9 +/- 0.6 kg) o r 45% (7.5 +/- 0.5 kg) carbohydrate. Furthermore, significant decrease s in total body far and waist-to-hip circumference were seen in both g roups, and the magnitude of the changes did not vary as a function of diet composition. Fasting plasma glucose, insulin, cholesterol, and tr iacylglycerol concentrations decreased significantly in patients eatin g low-energy diets that contained 15% carbohydrate, but neither plasma insulin nor triacylglycerol concentrations fell significantly in resp onse to the higher-carbohydrate diet. The results of this study showed that it was energy intake, not nutrient composition, that determined weight loss in response to low-energy diets over a short time period.