Cutting calories may slow the aging process, reduce the risk of disease, and result in a longer life span, a long-term study of monkeys suggests. The study confirms in primates what has long been known to be true in mice, worms, flies, and other species. Over 20 years, rhesus monkeys(アカゲザル)whose diets were not restricted were nearly three times more likely to have died than those whose calorie intake was reduced by 30%. The rate of cancers and cardiovascular disease in the dieting monkeys was also less than half of those permitted to eat as they pleased. It is unclear whether other primates, like humans, would experience the same benefit from a calorie-restricted diet.