title: Energy expenditure of adult male rhesus monkeys during the first 30 mo of dietary restriction.
abstract: Energy expenditure, activity, and body composition were measured in 30 adult male rhesus monkeys used in a study having the long-term goal of determining the effects of moderate dietary restriction (DR) on aging. All animals were fed a defined diet, with the restricted animals maintained at approximately 70% of the caloric intakes of the controls. After 12 mo of DR, body fat mass of restricted monkeys was 33% less than that of controls (P = 0.004), whereas lean body mass differences were not present until after 24 mo. At the 24- and 30-mo assessments, nighttime energy expenditure was significantly reduced (P < 0.01) in the restricted compared with control monkeys after adjustment for lean body mass differences, whereas morning, afternoon, and total energy expenditure were not significantly different (P > 0.05). No significant differences (P > 0.05) in activity were noticed between treatment groups at any time point. DR resulted in a prolonged decrease in resting energy expenditure, which could contribute to the possible life-extending action of this treatment.
authors.affiliation: Wisconsin Regional Primate Research Center, University of Wisconsin-Madison 53715-1299, USA.
authors.forename: J J
authors.initials: JJ
authors.lastname: Ramsey
authors.forename: E B
authors.initials: EB
authors.lastname: Roecker
authors.forename: R
authors.initials: R
authors.lastname: Weindruch
authors.forename: J W
authors.initials: JW
authors.lastname: Kemnitz
mesh_terms: D000818:Animals; D001823:Body Composition; D001824:Body Constitution; D004032:Diet; D004734:Energy Metabolism; D008253:Macaca mulatta; D008297:Male; D013997:Time Factors