Should scientists subject humans to research studies on CR to see whether it produces the same results in humans as in lab animals? What effect will CR have on psychosocial health and quality of life? Should CR replace other human weight-control strategies? Is CR even possible given the fact that humans have unrestricted access to food?
To answer these and other questions, the National Institute on Aging in collaboration with the National Institute of Diabetes, Digestive, and Kidney Diseases convened the Caloric Restriction Clinical Implications (CRCI) Advisory Group to consider opportunities of such research. The group, which included gerontologists, nutritionists, pharmacologists, physicians, and psychologists, published their findings and recommendations in a special issue of the Journals of Gerontology Series A: Biological Sciences and Medical Sciences (Special Issue I, March 2001, http://www.geron.org/journals/spcontents.html).
Caloric restriction is accomplished by restricting caloric intake far below what an animal would consume on its own. In animal studies, CR was found to extend life expectancy by 30 to 40 percent if initiated in early adulthood.
A panel of experts led by I-Min Lee of Harvard Medical School looked at whether there are physiological effects that occur with CR in humans that could plausibly explain the observed longevity of lab animals associated with CR. They also wrestled with the appropriate CR model in humans. Is it being thin over most of adult life or not gaining weight over time or expending more calories than eaten
Contact: Melanie Radkiewicz
The Gerontological Society of America