Effect of dietary macronutrients on postprandial incretin hormone release and satiety in obese and normal-weight women

The aim of the present study was to assess the effect of dietary macronutrients on postprandial incretin responses and satiety and hunger sensation in obese and normal-weight women. A total of eleven obese and nine normal-weight women were recruited for the assessment of plasma concentrations of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and insulin and the sensation of satiety and hunger using a visual analogue scale before and during a 6h period after administration of three different macronutrient test meals. The AUC(total) (GLP-1) and AUC(total) (GIP) values were decreased in obese women after the consumption of a fatty meal and all the test meals, respectively. However, the AUC(totalinsulin) value after a carbohydrate meal was greater in the obese group. The AUC(totalsatiety) value was decreased only after the intake of the protein meal in obese women when compared with normal-weight women. After the consumption of the fatty meal, a significant positive correlation between maximum satiety sensation and the AUC(totalGLP-1) value in the obese group and that between minimum hunger sensation and the AUC(totalGLP-1) value in the normal-weight group were observed. In conclusion, the findings of the present study suggest that: (1) satiety sensation after consumption of carbohydrate and protein meals in the obese group is related to the postprandial insulin response, while after consumption of a fatty meal, it is related to the postprandial GLP-1 release; (2) the postprandial GIP response does not influence the sensation of satiety and hunger; (3) the reduced GLP-1 release after the intake of a fatty meal in obese individuals may explain impaired satiety sensation; (4) the impaired postprandial GIP response is not related to the consumption of macronutrients and may be the early indicator of incretin axis dysfunction in obese women.