Research on aging suggests that dietary restrictions will help to slow aging to extend health and lifespan.
Eating such a diet has been shown to extend lifespan and delay age related disease in many species, but a recent genome wide analysis of 160 genetically distinct strains of D.melanogaster fruit flies published in Current Biology shows that health and lifespan are not linked under dietary restrictions.
According to the researchers from Kapahi Lab at Buck Institute average life and healthspan were increased, but the details are complicated.
Nutrient dependent changes in lifespan were measured and age related changes in physical activity were tracked to measure healthspan; 97% of the strains showed some health and lifespan extensions in response to dietary restriction, but only 50% showed significant positive responses to dietary restriction for both.
13% of the strains were more vigorous but died earlier with dietary restriction, 5% lived longer but had more time in poor health, and 32% showed no benefits or detriments or negative responses to both.
“Dietary restriction works, but may not be the panacea for those wanting to extend healthspan, delay age-related diseases, and extend lifespan,” said Pankaj Kapahi, Ph.D., Buck professor and senior author on the paper.
“Our study is surprising and gives a glimpse into what’s likely going to happen in humans, because we’re all different and will likely respond differently to the effects of dietary restriction. Furthermore, our results question the idea that lifespan extension will always be accompanied by improvement of healthspan.”
Genes were found to influence health and lifespan in a diet dependent manner using genome wide analysis.
The decima gene was identified which regulates lifespan in the fruit flies; inhibiting this gene extended lifespan by reducing the production of insulin like peptides but this did not improve age related decline in physical activities.
The daedalus gene was also identified, when inhibited this delayed the age related decline in physical activity upon dietary restriction but this only minimally influenced lifespan.
The lifespan and physical abilities were tracked for over 50,000 fruit flies during this study.
“It’s hard to ask and get relevant results in individuals,” said postdoc Kenneth Wilson, Ph.D. “With this method, we can ask questions in a much more robust manner and get answers at the population level.”
