Glycemic and insulinemic responses as determinants of appetite in humans

Background: The importance of the postprandial glycemic and insulinemic responses for appetite and energy intake (EI) is controversial. Objective: The aim of the study was to test the hypothesis that postprandial appetite sensations and subsequent El are determined by postprandial glycemic and insulinemic responses after the intake of a range of breakfast meals. Design: The study was a randomized, crossover meal test including 28 healthy young men, each of whom tested 10 of 14 breakfast meals. Each meal contained 50 g carbohydrate with various glycemic index and energy and macronutrient contents. Blood samples were taken, and appetite sensations were measured 3 h after the meals. Subsequently, El at lunch (EIlunch) was recorded. Results: The glycemic response was unrelated to appetite sensations, whereas the insulinemic response was positively associated with postprandial fullness (R-2 = 0.33, P < 0.05). In contrast, the insulinemic response was unrelated to the subsequent EIlunch whereas the glycemic response was positively associated with EIlunch (R-2 = 0.33, P < 0.05). Although no significant difference in Ellunch was observed between different breakfast conditions, a low breakfast EI was associated with a high EIlunch (R-2 = 0.60, P < 0.001). Conclusions: The current study does not support the contention that the postprandial glycemic response has an important effect on short-term appetite sensations, but a low-glycemic index meal may reduce subsequent EI. In contrast, postprandial insulin seems to affect short-term appetite sensations.