According to researchers, low body temperature, low insulin and high levels of a specific hormone seem to be linked to a slowdown of the aging process. It is now well known that calorie restriction increases the lifespan of animals. Now researchers at the National Institute of Aging have some new clues about slowing down the aging process. They compared a group of 500 healthy men, taking part in this study of aging, with a group of rhesus monkeys. They followed the men for 22 years, the monkeys for 12.
The monkeys were in two groups - one following a normal diet, the other on calorie restriction. The latter tended to have a lower body temperature, lower blood insulin levels and higher levels of a hormone called dehydroepiandrosterone sulphate (DHEAS). Researchers feel that these could be the three biological markers of aging. The same profile was found in the men who lived longest - even though they were not practising calorie restriction. This suggests that you don't need to starve yourself to extend your lifespan. But the research is still on in order to find what factors (other than calorie restriction) influence the levels of the aging biomarkers.