Calorie restriction may prolong life

Reported by Susan Aldridge, PhD, medical journalist

New tests show that reducing calories decreases insulin levels and body temperature, both markers of longevity.
Previous work has suggested that rodents and other short-lived species live longer when they follow a calorie-restricted diet. Now researchers at Louisiana State University reveal that there are signs this may be applicable to humans too.

A group of 48 healthy and sedentary men and women was assigned to one of four sub-groups - weight maintenance, calorie restriction (25 per cent less than usual), calorie restriction (12.5 per cent) and exercise (12.5 per cent increase in energy expenditure), and very low calorie diet. After six months, those on the calorie restricted diets had lost about ten per cent of their body weight. Those on the low cal diet lost about 14 per cent.

Those in the three intervention groups all had decreased insulin levels and those in the two calorie restriction groups (but not the very low cal group) had lowered body temperatures. Both these measures are known biomarkers for longevity. Further research is now needed to see if such changes actually have an impact on human aging - in other words, do you really live longer if you eat less?

Source
Journal of the American Medical Association 5th April 2006 Volume 295 pages 1539-1548