Data From: Dietary restriction extends lifespan across different temperatures in the fly

Dietary restriction (DR) has been consistently shown to extend lifespan across a range of taxa. However, recent findings question the universality of the DR longevity response, suggesting DR may not extend lifespan at lower temperatures in flies, and that the DR longevity response is an artifact of benign laboratory conditions. 

We re-test this hypothesis, measuring the lifespan of Drosophila melanogaster at the lab-standard 25°C, and at colder temperatures (18°C and 21°C) across a range of 5 diets. 

We found the DR longevity response to be robust, extending lifespan irrespective of temperature. Fecundity was measured as a positive control for the DR phenotype, and it was found that DR reduced egg laying.

We suggest results that question DR as a phenotype should not be overinterpreted readily, as variations in the experimental setup, genetic lines used, and diet-lifespan reaction norm may be responsible for discrepancies. Additionally, starting conditions that show a lifespan extension by DR and then changing the environment and/or genotype promises a more robust test of DR modulating factors.