The Longevity Diet

Photography by: Mark Viker
The Longevity Diet
The science behind CR
Does the CR diet work? It does for rats and monkeys. In his numerous animal studies on rodents and other small mammals, Fontana has found that restricting calories while also providing sufficient nutrition can lead to a 50 percent increase in lifespan. However, there's not much human research on restricting calories. "It's hard to find people willing to stay on a strict diet for the decades needed to prove whether or not they live longer than people who don't follow the diet," says David Katz, M.D., M.P.H., director of the Yale-Griffin Prevention Research Center in Derby, Conn.

But the results of human studies performed on middle-aged CR followers evaluating biomarkers, or conditions that lead to chronic disease, have been promising. A 2006 study published in the Journal of Clinical Endocrinology & Metabolism found that people on CR diets had reduced levels of a thyroid hormone that increases free-radical production, which can lead to cancer and other chronic diseases. And a report published in the January 2006 issue of the Journal of the American College of Cardiology found that the same group of people had above-average diastolic blood pressure, an indicator of future heart health.

The good, the bad, and the hungry
In a country where two-thirds of adults are overweight, few health professionals can argue with a plan that encourages followers to reduce total calorie intake by eliminating highly processed foods and replacing them with more wholesome foods. "For anyone who is overweight, reducing calories by eating more nutrient-dense foods will help reduce the risk of developing many chronic diseases like cancer, cardiovascular disease, osteoporosis, and arthritis," says Jeffrey Blumberg, Ph.D., professor at the Freidman School of Nutrition Science and Policy at Tufts University. "This diet may or may not increase your life span, but it can certainly help increase your health span."

But severe calorie restriction is a concern among many health professionals, and some mental health experts feel that counting every single calorie may not be so good for the psyche. "It depends on the motivation for the diet, whether it's strictly for health purposes or if it's a distraction used to fill a void in your life," says Glenn Berger, a psychotherapist in private practice in New York City. "Like any obsessive behavior, spending time thinking about each and every calorie consumed could be a way to avoid developing an authentic relationship, with yourself and with others."