You Are What You Eat: Hormone Receptors Improve Life Expectancy

You are what you eat, and that's truer now than ever before. A reduced caloric intake can increase life expectancy among many species. Yet researchers have often wondered why this is. Now, scientists have discovered that a hormone receptor may be one of the links between nutrition and life expectancy.

In order to examine how diet affects life expectancy, the researchers looked at the roundworm Caenorhabditis elegans. With a lifespan that only lasts about 20 days, this species is a perfect subject to examine the impacts of diet. After examining the worm, the scientists found that the receptor protein NHR-62 is involved in increasing the lifespan of the animals by up to 20 percent. There is, however, a catch.

In order for NHR-62 to increase the lifespan of the animals, their calorie intake needs to be reduced. By that same token, the receptor needs to be active for the reduced dietary intake to fully prolong the life of the worms. If NHR-62 is inactive, in fact, it seems as if this reduced intake has no real effect.

"It seems that there is an as yet unknown hormone which regulates lifespan using NHR-62," said Adam Antebi, one of the researchers, in a news release. "If we can identify this hormone and administer it to the worm, we may prolong its life without having to change its calorie intake."

That wasn't the only thing that the researchers found, though. They also discovered that a restricted diet affects the expression of genes dramatically. Out of the approximate 20,000 worm genes, 3,000 change their activity and 600 of these show a dependence on NHR-62. This seems to indicate that there are many other candidates for improving life expectancy.

So how did the round worms match up to humans? We have receptors similar to NHR-62, which means that the hormone receptors may not just control the maximum lifespan of worms; humans, too, could also be affected.

The findings could have major implications for human health. If scientists can identify the hormones that are involved in life expectancy, they could potentially use them to help improve health. That particular feat, though, is still a long ways away. Until then, just be careful what you eat.

The findings are published in the journal PLOS Genetics.