Calorie Restriction, Longevity, and Eating Disorders
Posted Jul 24 2009 10:47pm
Perhaps you have heard the buzz this week. The results are in from a 20-year longitudinal study which show that decreasing calorie intake by 30% results in life-extending metabolic changes that appear to slow the aging process. Hooray! For the monkeys that is...
The highly regarded experiment looked at 75 rheses monkeys, the latest in a long string of studies into Calorie Restriction (CR) and its effect on longevity. Studies like this aren't new. Researchers since the 1930's having been looking into how CR might be capable of extending the maximum lifespan of a species. Some results showed an increase in longevity of up to forty-percent. Results have boasted that CR delays the onset of almost all disease and even creates a new maximum lifespan. At the same time, CR was found to reduce the incidence and severity of most age-associated diseases, including cancer and cardiovascular disease.
Here's the problem (well, there is more than one...), while various studies have shown that CR extends the life span of rats, worms, dogs, and now monkeys, there is no evidence which suggests that CR leads to a longer lifespan in humans.
True, some studies suggest that reduced calorie consumption in humans is associated with benefits such as lower blood pressure and lower cholesterol, however, these same benefits can also be obtained through a more balanced approach to food and exercise ( click here for a related article form the Journal of Nutrition).
Something else: what the recent primate research does not allude to is that studies have shown that humans who adhere to a CR diet display many of the same symptoms associated with anorexia nervosa, including food obsession, increased hunger, and decreased sexual drive.
and, a very low Body Mass Index is associated with a higher risk of death.
So, if a client or patient says to you that he or she is thinking about adopting a CR lifestyle, I suggest you help them take another look. Given the evidence demonstrating the many potential health risks involved with a CR approach to diet in humans, it's best to think again.