A look at current research on the definite health and potential longevity benefits of calorie restriction in humans: "Animals who consume fewer calories live longer and healthier lives. Now, a seminal study at the University of California, San Francisco (UCSF) is testing whether the same is true for extreme dieters. The calorie restriction study centers on two primary questions: What allows people to live in a manner many consider food deprived? And does it slow down aging? Called CRONA (Caloric Restriction with Optimal Nutrition and Aging Study), the investigation is probing the biological processes affected by extremely low caloric intake, including the impact on telomeres - tiny pieces of DNA that protect cell chromosomes. Short telomeres have been linked to a host of health problems including diabetes, heart disease and premature death. The UCSF study is the first to broadly examine the psychological profile of successful extreme dieters, gauging how their cognitive sharpness, impulse control, stress and personality differ from normal eaters and overeaters. ... Testing and data collection will continue through summer. The scientists are still recruiting control subjects who are either obese or 'free eaters' - not restricting food intake but not overweight. Interested parties can email cronastudy@gmail.com. ... We need information about what it takes to change your eating pattern for a long time. There are so many diets out there - people lose weight for six months, then regain it. We need to study what it is about the calorie restrictors that makes them able to do this for years and years." The new information on the biological response to calorie restriction is, I think, much more valuable than yet another study on willpower in humans.

Link: http://www.ucsf.edu/news/2011/04/9740/extreme-dieting-does-it-lead-longer-lives