Carbohydrate balance predicts weight and fat gain in adults

Background: The prevention and treatment of obesity is a public health challenge. Objective: We investigated the effects of dietary composition, insulin sensitivity (S-1), and energy balance oil predicted changes in body composition. Design: In a randomized crossover design study, 39 normal-weight (n = 23), overweight (it = 8), and obese (n = 8) men and women (aged 25-36 y) each followed a 15-d isocaloric high-fat (HF; 50% fat) and high-carbohydrate [HC; 55% carbohydrate (CHO)] diet with a 4-6-wk washout period during the first year. During each treatment, energy balance was Measured while the subjects were inactive by using indirect calorimetry oil day 15, and S-1 wits measured by using a euglycemic clamp study (40 mU (.) m(-2 .) min(-1)) oil day 16. Weight and body composition were then measured annually for 4 y. The outcomes for fat mass, percentage body fat, and weight were measured by using a linear 2-stage mixed model. Results: CHO balance (day 15) and S-1 (day 16) oil the HC diet were highly and significantly correlated (r = 0.55, P < 0.001). Oil the HC diet, the subjects who had a higher positive CHO balance (day 15) gained less fat mass (P < 0.001), percentage body fat (P = 0.006) and weight (P = 0.024) over time. When adjusted for S-1, CHO balance remained a significant predictor of changes in fat mass (P = 0.021) and percentage body fat (P = 0.025). Conclusions: Oil a HC diet, the Subjects who had a higher positive CHO balance on day 15 while they were inactive gained less fat mass during 4 y, a predictive effect independent of S-1. As suggested in rodents. the capacity to expand the glycogen pool might reduce energy intake and protect against fat and weight gain.