Dietary restriction in rats and mice: a meta-analysis and review of the evidence for genotype-dependent effects on lifespan.
Level 5 - mechanism / opinion, no new human data
Meta-analysis of animal laboratory experiments with no human data
PubMed 22210149 · doi:10.1016/j.arr.2011.12.006
What was done
Meta-analysis and review evaluating laboratory experiments published from 1934 to 2012 that measured the effects of dietary restriction (DR) on median and maximum lifespan across various strains of rats and mice.
What was found
In half of all rat experiments, dietary restriction increased median lifespan by 14-45%, whereas effects in mice were weaker at 4-27%. Inbred mouse strains showed the least favorable responses; male DBA/2 mice and several strains from the ILSXISS recombinant inbred panel did not live longer, and ILSXISS strain 114 showed confirmed lifespan shortening. Furthermore, a cited study demonstrated that dietary restriction did not increase median lifespan in wild-derived mice.
Why it matters
Lifespan extension via dietary restriction is heavily dependent on genetic background rather than being a universal biological effect across mammals. These genetic divergences must be accounted for before attempting translation to genetically heterogeneous species like humans.
Limits
The abstract does not state the total number of studies or individual animals included in the meta-analysis. Findings are restricted to laboratory rodents, and the selective breeding of laboratory strains limits direct extrapolation to outbred wild populations and humans.
Cited by
- supports Caloric restriction extends lifespan in animals compared to ad libitum feeding.