Vitamins May Shorten Lifespan, Animal Study
Regularly taking vitamins could actually shorten your lifespan, a new animal study suggests.
Scientists found that high doses of vitamins C and E shrunk the lifespan of voles by up to a quarter, according to a new study published in the journal Biology Letters.
In the study, researchers fed field voles a diet supplemented with high levels of vitamin E or vitamin C from the age of two months in either warm or cold conditions. Afterwards, investigators compared the longevity of voles given vitamins to those fed a regular diet without vitamins.
Researchers explained that high doses of dietary antioxidants like vitamins are often suggested to stall the process of cellular aging by reducing the damage caused by free radicals on proteins, lipids and DNA.
Past studies found that administering particular vitamin supplements, despite the supplements' limited effectiveness in reducing free radical damage, could lengthen the longevity of mice.
However, the latest study on voles found the opposite. The study revealed that voles in cold conditions fed supplements of vitamin E or vitamin C lived much shorter on average than those fed a regular diet. Supplemented voles living in warm conditions also had shorter lives than those fed a regular diet.
The findings revealed that compared to animals on a regular diet, lifespan was reduced by 11 percent and 26 percent for vitamin E and C voles in the cold and by 17 percent and 18 percent for vitamin E and C voles in the warm. However, researchers found that vitamin supplements did have some effect in decreasing free radical damage.
"When we began our research, we expected that voles' lifespans would be boosted by the vitamin supplements in a similar way to the mice we had tested previously, so we were surprised to see that was not the case. Our findings suggest that major differences exist in the effects of high doses of antioxidants on oxidative damage and lifespan across species," first author Professor Colin Selman of the University of Glasgow's Institute of Biodiversity, Animal Health and Comparative Medicine, said in a news release.
"It's unlikely that randomized controlled trials examining the effects of antioxidant supplementation on human lifespan would be possible, so we are dependent on the results of animal studies. It's impossible at this stage to extrapolate the results from this small amount of data we have on voles and mice but it does suggest that caution is warranted in the use of high doses of antioxidant vitamins," added lead researcher Professor John Speakman, of the University of Aberdeen.