Gabe Mirkin, M.D.
Many studies have shown that animals on calorie
restricted diets live longer, have less diabetes, heart attacks and
cancers and appear younger. In the latest work at the Wisconsin
National Primate Research Center, monkeys eating only 30
percent of their normal caloric intake live much longer and
appear much younger than those eating their full diets (American
Journal of Physiology-Endocrinology and Metabolism, August
2006).
Nobody really knows how calorie restriction with
adequate nutrients prolongs life and prevents disease, or
whether the animal studies can be applied to humans. The
leading theory for calorie restriction with adequate nutrition is that
it teaches your mitochondria to burn food to produce much lower
amounts of oxidants. Mitochondria are the furnaces in cells that
turn food into energy. Converting food to energy produces free
electrons that form reactive chemicals called oxidants that can
bind to and damage DNA and shorten life. Exercise also
reduces the amount of oxidants and so should prolong life.
Another theory is that excess calories cause fat cells to fill up
with fat. Full fat cells produce cytokines that turn on your
immunity to cause inflammation that damages all the cells in your
body, which would shorten life and cause disease. Anything that
prevents excess fat storage should reduce inflammation and thus
prolong life. Exercise burns calories, and food restriction lowers
calorie intake in humans as well as animals.
January 15, 2007