REPLACEMENT OF DIETARY-FAT BY SUCROSE OR STARCH - EFFECTS ON 14D AD-LIBITUM ENERGY-INTAKE, ENERGY-EXPENDITURE AND BODY-WEIGHT IN FORMERLY OBESE AND NEVER-OBESE SUBJECTS

OBJECTIVE: To investigate the impact of a high-sucrose diet vs a high- starch and a high-fat diet on 14d ad libitum energy intake, body weigh t, energy expenditure and sympathoadrenal activity. MEASURMENTS: Food intake; body weight and composition (bioelectrical impedance); 24h ene rgy expenditure, substrate oxidation rates, spontaneous physical activ ity, heart rate and appetite sensations in a respiration chamber (VAS scores); plasma catecholamine concentration and blood pressure. SUBJEC TS: Twenty normal-weight, heathy women, 9 post-obese (body mass index (BMI): 22.9 +/- 0.7 kg/m(2)) and la closely matched controls (BMI: 22. 6 +/- 0.4 kg/m(2)). RESULTS: Average a 14d ab libitum energy intake wa s 13% and 12% lower on the starch diet compared with the sucrose and f at diets, respectively (P < 0.05). In both post-obese and normal-weigh t subjects, body weight and fat mass decreased significantly on the st arch diet (by 0.7 +/- 0.2 kg and 0.4 +/- 0.1 kg, respectively, P < 0.0 5). No changes were observed on the fat or sucrose diets. After 14d on the sucrose diet, 24h energy expenditure as well as postprandial plas ma adrenaline and noradrenaline concentrations, were significantly inc reased compared with the other two diets. Overall satiety and palatabi lity ratings were also highest apr the sucrose diet. CONCLUSION: Intak e of a 14-d ad libitum high-starch diet decreased energy intake anti b ody weight compared with a high-fat or high-sucrose diet. The increase d energy expenditure observed on the sucrose-rich diet can probably be explained both by the increased intake od energy and fructose (mainly from sucrose) on this diet.