title: Fasting and postprandial total ghrelin remain unchanged after short-term energy restriction.
abstract: Adaptations that promote positive energy balance appear in response to dietary restriction. The aim of this study was to determine whether fasting and postprandial total ghrelin increase in response to short-term energy restriction. Fifteen adult male subjects were subjected to a 4-d energy restricted diet (-800 kcal/d). Body weight and composition, resting energy expenditure, respiratory quotient, fasting and postprandial appetite scores, and fasting and postprandial serum leptin and total ghrelin were determined before and after dietary intervention. Despite the fact that fat mass remained unchanged after the 4 d, fasting (-36%; P </= 0.01) and postprandial serum leptin (-27%; P = 0.01) were significantly reduced. A significant reduction in total ghrelin was observed after the meal (P </= 0.05); however, fasting and postprandial total ghrelin remained unchanged at the end of the intervention. Although leptin was a significant correlate of appetite before and after the intervention, no such associations were noted for total ghrelin. Finally, a significant relation between total ghrelin and respiratory quotient was noted at the onset of the diet (r = 0.63; P </= 0.01). Fasting and postprandial total ghrelin levels remain unchanged after short-term energy restriction despite a significant fall in leptin.
authors.affiliation: School of Human Kinetics, and Department of Biochemistry, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5. edoucet@uottawa.ca
authors.forename: Eric
authors.initials: E
authors.lastname: Doucet
authors.forename: Marjorie
authors.initials: M
authors.lastname: Pomerleau
authors.forename: Mary-Ellen
authors.initials: ME
authors.lastname: Harper
mesh_terms: D000328:Adult; D001066:Appetite; D031204:Caloric Restriction; D002149:Energy Intake; D004734:Energy Metabolism; D005215:Fasting / Q000097:blood*; D054439:Ghrelin; D006801:Humans; D020738:Leptin / Q000097:blood; D008297:Male; D036361:Peptide Hormones / Q000097:blood*; D019518:Postprandial Period / Q000502:physiology*; D012016:Reference Values; D012119:Respiration; D012146:Rest; D013997:Time Factors
chemical_list: D054439:Ghrelin; D020738:Leptin; D036361:Peptide Hormones