Permanent diet may equal longer life

The practice of caloric restriction -- essentially, going on a permanent diet -- greatly reduces the risk of age-related diseases and even postpones death. It has been shown to significantly extend the lives of yeast, worms, flies, spiders, fish, mice and rats.

Now, in a much-anticipated study funded by the National Institutes of Health, many of the same benefits have been demonstrated in primates, the best evidence yet that caloric restriction would help people.

The findings, published in the journal Science, tracked rhesus monkeys that were on a reduced-calorie regimen for as long as 20 years. The animals' risk of dying from cancer, heart disease and diabetes fell by more than two-thirds.

Is caloric restriction the solution?

"Mild caloric restriction is beneficial to everybody," said Dr. Luigi Fontana, a medical professor at Washington University in St. Louis.

Caloric restriction has consistently produced health benefits for animals.

In the new study, scientists tracked 76 adult rhesus monkeys from the Wisconsin National Primate Research Center starting in 1989. Half the animals were fed a typical diet of lab chow, and the rest got a version with a higher concentration of vitamins and minerals to make up for the 30% reduction in chow quantity.