Calories do not explain extension of life span by dietary restriction in Drosophila

PLoS Biol. 2005 Jul;3(7):e223. doi: 10.1371/journal.pbio.0030223. Epub 2005 May 31.


Dietary restriction (DR) extends life span in diverse organisms, including mammals, and common mechanisms may be at work. DR is often known as calorie restriction, because it has been suggested that reduction of calories, rather than of particular nutrients in the diet, mediates extension of life span in rodents. We here demonstrate that extension of life span by DR in Drosophila is not attributable to the reduction in calorie intake. Reduction of either dietary yeast or sugar can reduce mortality and extend life span, but by an amount that is unrelated to the calorie content of the food, and with yeast having a much greater effect per calorie than does sugar. Calorie intake is therefore not the key factor in the reduction of mortality rate by DR in this species.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Caloric Restriction*
  • Diet
  • Dietary Carbohydrates / administration & dosage
  • Drosophila melanogaster / physiology*
  • Energy Intake
  • Feeding Behavior
  • Female
  • Longevity / drug effects
  • Longevity / physiology*
  • Tetracycline / pharmacology
  • Yeasts


  • Dietary Carbohydrates
  • Tetracycline