title: Postprandial plasma ghrelin is suppressed proportional to meal calorie content in normal-weight but not obese subjects.
abstract: Circulating levels of the gastric hormone ghrelin rise before and decrease after a meal. In normal-weight subjects, postprandial suppression of ghrelin is proportional to calories consumed. Obese individuals have lower fasting ghrelin levels; however, it is unclear whether the obese show normal postprandial suppression. This study aimed to compare postprandial ghrelin responses in normal-weight and obese subjects, using mixed macronutrient meals with varied fat and calorie content. Postprandial ghrelin response was measured in normal-weight insulin-sensitive subjects and obese insulin-resistant subjects, after six test meals with different fat and calorie content (250-3000 kcal). Increasing the calorie content of meals in normal-weight subjects progressively lowered nadir levels of ghrelin. The obese had lower fasting ghrelin levels, and the reduction after the consumption of all test meals was less than the normal-weight subjects. The lowest postprandial levels in the obese were no different to the nadir in normal-weight volunteers after 1000-, 2000-, and 3000-kcal meals. Thus, circulating ghrelin levels decreased in normal-weight subjects after mixed meals. Obese subjects demonstrated a much reduced ghrelin postprandial suppression. This reduced suppression may influence satiety, thus reinforcing obesity.
authors.affiliation: Department of Metabolic Medicine, Imperial College London, Hammersmith Hospital, London W12 0NN, UK.
authors.forename: C W
authors.initials: CW
authors.lastname: le Roux
authors.forename: M
authors.initials: M
authors.lastname: Patterson
authors.forename: R P
authors.initials: RP
authors.lastname: Vincent
authors.forename: C
authors.initials: C
authors.lastname: Hunt
authors.forename: M A
authors.initials: MA
authors.lastname: Ghatei
authors.forename: S R
authors.initials: SR
authors.lastname: Bloom
mesh_terms: D002149:Energy Intake; D005215:Fasting; D054439:Ghrelin; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D007700:Kinetics; D009765:Obesity / Q000097:blood*; D036361:Peptide Hormones / Q000097:blood*; D019518:Postprandial Period / Q000502:physiology*; D012016:Reference Values
chemical_list: D054439:Ghrelin; D036361:Peptide Hormones