Comparative and meta-analytic insights into life extension via dietary restriction.
Level 1 - systematic review of randomized trials
Level 1 by design analogy (meta-analysis of experimental non-human studies), not clinical CEBM.
PubMed 22268691 · doi:10.1111/j.1474-9726.2012.00798.x
What was done
Conducted a comparative meta-analysis across published studies and species (including yeast, nematode worms, fruit flies, rodents, and non-model organisms) to quantitatively evaluate the effects of dietary restriction on lifespan and age-dependent versus age-independent mortality rates.
What was found
Dietary restriction significantly increased lifespan overall, though the effect was smaller in males and in non-model organisms. The proportion of protein intake was more important for life extension than the degree of caloric restriction. Reductions in both age-dependent and age-independent mortality rates contributed to life extension in standard laboratory model species. No specific numerical values, sample sizes, or effect estimates were provided in the abstract.
Why it matters
It provides broad comparative evidence that dietary restriction benefits are modulated by sex, species adaptation, and specifically protein intake rather than simple caloric reduction.
Limits
The abstract reports no exact numbers, effect sizes, sample sizes, or counts of included studies. The analysis relies on animal and cellular laboratory models, and the findings suggest laboratory adaptation may limit generalizability to wild populations or humans.
Cited by
- supports Caloric restriction extends lifespan in animals compared to ad libitum feeding.