title: Appetite, food intake, and plasma concentrations of cholecystokinin, ghrelin, and other gastrointestinal hormones in undernourished older women and well-nourished young and older women.
abstract: Aging is associated with a reduction in appetite and food intake, predisposing to protein-energy malnutrition. The causes of this "anorexia of aging" are largely unknown. To investigate possible contributions of enhanced satiating effects of cholecystokinin (CCK) and reduced stimulation of food intake by ghrelin, eight undernourished older women [age, 80.4 +/- 2.6 yr; body mass index (BMI), 16.9 +/- 0.57 kg/m(2)], eight well-nourished older women (age, 77 +/- 0.9 yr; BMI, 23.7 +/- 0.8 kg/m(2)), and eight well-nourished young women (age, 22 +/- 1.3 yr; BMI, 20.5 +/- 0.4 kg/m(2)), in randomized order, ate on 1 d a 280-kCal preload and on the other no preload, 90 min before an ad libitum meal. At baseline the undernourished, but not the well-nourished, older subjects were less hungry (P < 0.05) than young subjects. Before and after the preload, plasma CCK levels were higher (P < 0.05) in the older than young subjects, with no difference between the older groups. Plasma ghrelin concentrations were higher in the undernourished than both well-nourished groups and decreased similarly after the preload in all groups. The preload suppressed food intake in the well-nourished older and young subjects (P < 0.05), but was without effect in the undernourished old. These observations suggest that reduced basal hunger, rather than increased meal-induced satiety, contributes to the anorexia of aging and that changes in CCK and ghrelin are unlikely to be responsible.
authors.affiliation: Department of Medicine, University of Adelaide, Royal Adelaide Hospital, North Terrace, Adelaide, South Australia 5000, Australia.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Sturm
authors.forename: Caroline G
authors.initials: CG
authors.lastname: MacIntosh
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Parker
authors.forename: Judith
authors.initials: J
authors.lastname: Wishart
authors.forename: Michael
authors.initials: M
authors.lastname: Horowitz
authors.forename: Ian M
authors.initials: IM
authors.lastname: Chapman
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism*; D001066:Appetite / Q000502:physiology*; D001786:Blood Glucose / Q000378:metabolism; D002766:Cholecystokinin / Q000097:blood*; D004040:Dietary Carbohydrates / Q000378:metabolism; D004041:Dietary Fats / Q000378:metabolism; D004435:Eating / Q000502:physiology*; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D005768:Gastrointestinal Hormones / Q000097:blood*; D054439:Ghrelin; D006801:Humans; D009748:Nutrition Disorders / Q000097:blood*; D036361:Peptide Hormones / Q000097:blood*; D012528:Satiety Response / Q000502:physiology
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D005768:Gastrointestinal Hormones; D054439:Ghrelin; D036361:Peptide Hormones; D002766:Cholecystokinin