A new report in Nature Communications offers the first concrete evidence that a calorie restricted diet – when planned responsibly – can prolong life and help prevent certain diseases. The study, which examined the diets of rhesus monkeys, confirms the connection between food and lifespan in primates and experts strongly believe the findings pertain to humans as well.
The study began in 1989 when researchers at the Wisconsin National Primate Research Center in Madison started tracking the health of 76 captive rhesus monkeys. When the monkeys hit adulthood (ages 7 to 14), half of them were allowed to eat whatever they wanted, while the other half were put on a strict, nutrient-dense diet of 30 percent less calories. The results show that the monkeys with unlimited diets were three times more likely to develop chronic disease and die at any age.
According to study co-author Rozalyn Anderson, the calorie-restricted monkeys had better insulin sensitivity, less fat, and healthier lipid levels than the other group – all factors that contribute to lower disease risk. They were also more physically active, which helps delay aging.
"Because monkeys are so closely related to humans, we absolutely believe these results relate to human health," says Anderson. "However, I don't suggest you go out and cut 30 percent of your calories. That would leave most people without enough energy to keep working and living at maximum capacity."
Instead, she suggests taking smaller steps to improve your diet. They could pay off big time down the road. "Small-scale changes can have large-scale health effects, whether in monkeys or in people," she says.