Posted Aug 11, 2009
People who believed calorie restriction wouldn’t extend life in primates might now have to declare themselves monkey’s uncles.
A 20-year study finds that rhesus monkeys fed a nutritious but low-calorie diet have fewer age-related diseases than counterparts on a normal diet, researchers report July 10 in Science. Also, MRIs reveal less shrinkage with age in areas important for decision-making and controlling movement in the brains of calorie-restricted animals, report Ricki Colman and Richard Weindruch of the Wisconsin National Primate Research Center at the University of WisconsinMadison and colleagues.
The findings may have ramifications for fighting aging and disease in humans, says Luigi Fontana of Washington University in St. Louis and the Italian National Health Service in Rome. “I’m confident that everything that happens in [nonhuman] primates will happen in humans,” he says.
Calorie restriction has already been shown to extend lifespan in fruit flies, yeast, worms, mice and dogs.
The primate study began in 1989 with 30 adult male monkeys. In 1994, 30 female and 16 more male monkeys were added. Over the course of the study, monkeys on the full-calorie diet were three times more likely to die from an age-related disease than monkeys that ate 30 percent fewer calories, the researchers found.
Since the study began, 21 of 38 control monkeys and 14 of 38 calorie-restricted monkeys have died. Of the control monkeys, 14 died of age-related causes, such as cancer, heart disease or diabetes. In the calorie-restricted group, only five died from aging-associated diseases, and none have developed symptoms of diabetes.
“We were frankly blown away by these findings,” Weindruch says.
The maximal lifespan of rhesus monkeys is about 40 years, so researchers won’t know for another decade or two if- or for how long – calorie restriction can prolong life in primates.
Date: Aug 9, 2009
