March 6, 2018

Want to live longer? Eat less.  

That was the finding of a previous study by researchers at the Wisconsin National Primate Research Center (WiNPRC). And now, those same researchers may have discovered why.

“We knew that restricting calories helps monkeys to live longer, healthier lives, but we did not understand the basis for this extraordinary finding,” said Rozalyn Anderson, a professor and medicine and one of the study’s authors. Anderson worked closely with WiNPRC’s Dr. Ricki Colman, whose colony of rhesus monkeys was studied. “We are now at the beginning of a very exciting journey to discover how calorie restriction works on the molecular level.” Colman is a WiNPRC senior scientist and assistant professor at the University of Wisconsin-Madison.

Two groups of rhesus monkeys were studied for two years – one fed a normal diet while the other ate a diet with 30 percent fewer calories. The research team focused on the liver, because that is where nutrients are processed, and because it plays a key role in metabolic health. Through their research, the team catalogued more than 20,000 molecules in the rhesus liver and analyzed the data.

What the researchers found is that the lower calorie diet changed the way the liver was working, including how it metabolized proteins, carbohydrates, and lipids. Most surprising? The fact that calorie restriction was changing the metabolism on a genetic level using RNA processing.

“Although for some it will not be a surprise that metabolism is important to how calorie restriction works, we are talking about a dietary intervention after all,” said Anderson. “What is more interesting is the recent work showing profound metabolic effects in a whole host of age-associated diseases that are otherwise unrelated. We think that the metabolic response to calorie restriction is at the very heart of its ability to delay aging and the onset of age-related disease.”

While the implications of this discovery are still forthcoming, it’s certainly significant. In the meantime, keep on living, breathing, and eating – just not too much eating.

Photo credit: Kathy West for the California National Primate Research Center