Skip navigation

Current DateTime: 04:02:15 25 Nov 2009
LinksList Documentid: 24355697
  • Runway Angels

      The superbowl of fashion shows, models walk down the runway at the 2009 Victoria's Secret Show.

  • Smartphone Guide

      Here's a need-to-know guide to nine devices, based on features, price, network and platform.

  • Wines for the Holidays

      Not quite sure what wine to pair with Turkey or Creme Brulee? Our experts do.

Low-cal diet slows aging in monkeys
By: The Associated Press | 09 Jul 2009 | 12:23 PM ET
Text Size
Next step is finding out how calorie restriction impacts human lifespan

WASHINGTON - A 20-year study found cutting calories by almost a third slowed the aging of monkeys and fended off death.

This is not about a quick diet to shed a few pounds. Scientists have long known they could increase the lifespan of mice and more primitive creatures — worms, flies — with deep, long-term cuts in what should be normal consumption.

Now comes the first evidence that it delays the diseases of aging in primates, too — rhesus monkeys living at the Wisconsin National Primate Center. Researchers reported their study Friday in the journal Science.

What about those other primates, humans? Nobody knows yet if people in a world better known for overeating could stand the deprivation long enough to make a difference, much less how it would affect our more complex bodies. Still, small attempts to tell are under way.

"What we would really like is not so much that people should live longer but that people should live healthier," said Dr. David Finkelstein of the National Institute on Aging. The Wisconsin monkeys seemed to do both.

"The fact that there's less disease in these animals is striking," Finkelstein said.

The tantalizing possibilities of caloric restriction date back to rodent studies in the 1930s. But it is a hot topic today among researchers trying to understand the different processes that make our bodies break down with age, so maybe some of them could be delayed or reversed.

Captive rhesus monkeys have an average lifespan of 27 years, so spotting an effect takes a lot longer than in short-lived mice. The newest study involves 76 monkeys — 30 tracked since 1989 and 46 since 1994. They were normal-sized adults eating a normal diet for a captive monkey, a special vitamin-enriched chow plus some fruit treats.

Then researchers at the University of Wisconsin, Madison, assigned half the monkeys to the reduced-calorie diet, cutting their daily calories by 30 percent but ensuring what they did eat was properly nourishing.

Less disease and death
So far, 37 percent of the monkeys who kept their regular diet have died of age-related diseases — compared with just 13 percent of the calorie-cut monkeys, a nearly three-fold difference, the researchers reported. A handful of other monkeys died of unrelated conditions, such as injury, not deemed affected by nutrition.

Death was not the only change. The calorie-cut monkeys had less than half the incidence of cancerous tumors or heart disease as the monkeys who ate normally. Brain scans showed less age-related shrinkage in the dieting monkeys. They also retained more muscle, something else that tends to waste with age.

Compare two cage-by-cage photos of the monkeys and the difference is obvious: A 29-year-old monkey happens to be the oldest non-dieting monkey still alive, and a 27-year-old the oldest still-living dieter. Yet the dieting monkey looks many more years younger than his fatter, frumpier neighbor, not just a mere two.

"All these pieces put together provide rather convincing evidence in our view that caloric restriction can slow the aging process in a primate species," said lead researcher Dr. Richard Weindruch, a University of Wisconsin professor heading the NIA-funded study.

Metabolic shift?
He contends that somehow the diet change is reprogramming metabolism in a way that slows aging.

The federal government is funding a small study to see if some healthy normal-weight people could sustain a 25 percent calorie cut for two years and if doing so signals some changes that might, over a long enough time, reduce some age-related disease.

But NIA's Finkelstein cautions that people should not just try this on their own; cutting out the wrong nutrients could cause more harm than good. Just follow commonsense healthy lifestyle advice, he said.

"Everyone's obviously looking for the magic pill," and there's not one, Finkelstein said. "Watch what you eat, keep your mind active, exercise and don't get run over by a car."

Copyright 2009 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
Tools:
Print EmailAdd This share icon
  • digg share

CNBC HIGHLIGHTS

  • Remember when auto shows were major events where new models could generate buzz?
  • Swine Flu Needle
  • CNBC’s Mike Huckman visits a cutting-edge plant to see how the flu vaccine of the future is being made.
  • People who bottle up their anger at work are up to five times more likely to suffer a heart attack, a study found.
  • Playboy Logo
  • Playboy will outsource its publishing operations in a bid to become profitable again.
  • A new McDonald's in Manhattan is the nation's first to sport a sleek, chic interior imported from stores in London and Paris.
  • For nearly three decades, these on-call experts have been dishing advice on how to – and not to – cook turkey.
ADD COMMENTS
Remaining characters


Current DateTime: 01:26:08 25 Nov 2009
LinksList Documentid: 29778428

Current DateTime: 01:02:04 25 Nov 2009
LinksList Documentid: 29779196

Current DateTime: 02:05:46 25 Nov 2009
LinksList Documentid: 29779199

Current DateTime: 01:02:04 25 Nov 2009
LinksList Documentid: 29779198
  Data is a real-time snapshot  *Data is delayed at least 15 minutes
Global Business and Financial News, Stock Quotes, and Market Data and Analysis

© 2009 CNBC, Inc.  All Rights Reserved.
A Division of NBC Universal
Thomson ReutersThomson Reuters