Jul 10, 2008

In the quest for the Fountain of Youth, researchers say that there is one antiaging trick that has been found to work — eating less. The formula for extending human lifespan by up to five years has now been accepted by leading researchers. 

Eating less could add years to your life, several experts now say. And done in moderation, it could at least help you live a more healthy life, reports LiveScience. 

While little short of a nip-and-tuck will make you look younger, calorie restriction, as it is called, is as close to a real Fountain of Youth as any known technique comes. Even scientists who are cautious about anti-aging hype say it works, both by cutting risks for some diseases and by allowing all body cells, somehow, to hang in there longer. 

“There is plenty of evidence that calorie restriction can reduce your risks for many common diseases including cancer, diabetes and heart disease,” says Saint Louis University researcher Edward Weiss, who last week announced a new study that brings fresh understanding to how it works. “And you may live to be substantially older.” 

Here’s a rough rule of thumb that many experts generally agree on now: Eat 15% less starting at age 25 and you might add 4.5 years to your life, says Eric Ravussin, who studies human health and performance at the Pennington Biomedical Research Center in Louisiana. 

One important caveat: Ravussin’s estimate is based mostly on studies of other animals and only preliminary research in humans. But the work by Weiss and others is unlocking the mysteries of aging and suggesting the animal studies apply to humans. “There is absolutely no reason to think it won’t work,” Live-Science quoted Ravussin as saying. 

Perhaps even more promising, though in early stages of research, are drugs designed on the basis of what’s been learned from calorie-restriction studies. Those drugs would target human cells to deliver the same benefits, turning off bad things and turning on good things to extend cell life in general, or offer new therapies and cures to vexing diseases like Alzheimer’s and cancer. 

If you can hang in there until these promising new drug therapies are developed, you may live in a world where lifespan increases by 10 to 15 years, researchers say. Don’t plan on living to be 200, Ravussin said, “but I think we’re going to gain quite a few years.” 

Scientists aren’t sure exactly why calorie restriction slows aging. But they’re on the verge of a firm understanding. In a nutshell, it is thought to lower metabolic rate and cause the body to generate fewer damaging “free radicals”. One hypothesis is that it decreases a thyroid hormone, triiodothyronine (T3), which then slows metabolism and tissue aging. 

Evidence that calorie restriction boosts lifespans in rodents is solid. Christiaan Leeuwenburgh of the University of Florida’s Institute on Aging showed in 2006 that eating just 8% less and exercising a little more over a lifespan can reduce or even reverse aging-related cell and organ damage in rats. 

Various studies have shown that cutting calories by 20 to 40% significantly both extends life and, with a little exercise, leaves old animals in better shape. 

Eating fewer calories also reduces agerelated chronic diseases such as cancers, heart disease, and stroke in rodents. That’s important because it suggests ways to not just make us live longer, but to allow us to age more gracefully, healthwise.