title: Counting calories in Drosophila diet restriction.
abstract: The extension of life span by diet restriction in Drosophila has been argued to occur without limiting calories. Here we directly measure the calories assimilated by flies when maintained on full- and restricted-diets. We find that caloric intake is reduced on all diets that extend life span. Flies on low-yeast diet are long-lived and consume about half the calories of flies on high-yeast diets, regardless of the energetic content of the diet itself. Since caloric intake correlates with yeast concentration and thus with the intake of every metabolite in this dietary component, it is premature to conclude for Drosophila that calories do not explain extension of life span.
authors.affiliation: Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, USA.
authors.forename: Kyung-Jin
authors.initials: KJ
authors.lastname: Min
authors.forename: Thomas
authors.initials: T
authors.lastname: Flatt
authors.forename: Indrek
authors.initials: I
authors.lastname: Kulaots
authors.forename: Marc
authors.initials: M
authors.lastname: Tatar
mesh_terms: D000375:Aging / Q000502:physiology*; D000824:Animal Nutritional Physiological Phenomena / Q000502:physiology; D000818:Animals; D031204:Caloric Restriction / Q000379:methods; D004331:Drosophila melanogaster / Q000502:physiology*; D002149:Energy Intake / Q000502:physiology*; D005260:Female; D007814:Larva / Q000502:physiology; D008136:Longevity / Q000502:physiology; D008297:Male; D015003:Yeasts