Does Intermittent Fasting Mimic the Anti-Aging and Health Benefits of Calorie Restriction in Humans?

Longer Life Foundation Longevity Research Program:
John Holloszy M.D., Director
Luigi Fontana M.D., Ph.D., Associate Director

Project Overview:
Our research interest is in preventive gerontology, i.e. finding ways to maintain health and functional capacity and of protecting against the metabolic and degenerative diseases of middle and old age. Severe calorie restriction (CR) slows aging, has a protective effect against cancer and increases maximal longevity in rats and mice. We have been obtaining data on members of the Calorie Restriction Society, who practice severe, long-term CR, to determine whether CR also has major health and anti-aging effect in humans. We have found that CR powerfully protects against atherosclerosis, type 2 diabetes and hypertension, and not only slows, but also reverses the increases in stiffness of the arteries and heart, and the decrease in heart rate variability, that usually occur with aging. Very few people are willing or able to practice severe long-term CR.

We are, therefore, searching for other interventions that have similar benefits. One possibility we have been investigating is protein restriction. We find that protein restriction is almost as difficult to implement as CR, and it does not induce the same health benefits. During the next year, we plan to a) examine the effect of severe CR on gene expression in mucosal biopsies of the distal colon of CR Society members, and compare them to those of age-matched controls, to evaluate whether CR reduces cancer risk, and b) initiate a study on the effects of intermittent fasting (IF) to determine whether IF a) mimics the beneficial effects of CR, and b) is less difficult than CR.