High protein vs high carbohydrate hypoenergetic diet for the treatment of obese hyperinsulinemic subjects

OBJECTIVE: To test the hypothesis that hyperinsulinemic obese subjects woul d respond differently to changes in the composition of hypoenergetic diets. DESIGN: A 4-week randomized dietary intervention trial. SUBJECTS: Thirteen male obese hyperinsulinemic normoglycemic subjects were divided into two groups and fed hypoenergetic diets providing 80% of their resting energy expenditure (REE). One group received a high-protein diet (H P; 45% protein, 25% carbohydrates, and 30% fat as percent of dietary energy ) and the other a high-carbohydrate diet (HC; 12% protein, 58 carbohydrates and 30% fat), MEASUREMENTS: Anthropometry, body composition, fasting serum insulin and li pids, and REE were performed before and after the feeding period. RESULTS: Weight loss was higher in the HP than HC group (8.3 +/- 0.7 vs 8.0 +/- 0.6 kg, P < 0.05). There was a decrease in body fat in both groups, wh ereas body water decreased significantly more in the HP group. REE decrease d more in the HC than the HP group (- 384.3 +/- 84.6 vs - 132.3 +/- 51.0 kc al, P < 0.05). Serum total cholesterol, Priglycerides and LDL cholesterol d ecreased significantly to a similar extent in both diet groups, while HDL c holesterol was decreased significantly only in the HP group. Mean fasting i nsulin decreased significantly in both diet groups and reached the normal r ange only in the HP group. CONCLUSION: A low-carbohydrate (LC), HP hypoenergetic diet could be the die t composition of choice for a weight-reducing regimen in obese hyperinsulin emic subjects.