Researchers at UW-Madison have found that limiting calorie intake later in life can stall some of the muscle deterioration that normally accompanies aging.
Reported in the June 1997 FASEB (Federation of American Societies for Experimental Biology) Journal, the research involved age-related fiber loss and enzyme and gene abnormalities in rat muscle.
"We were surprised to find that initiating calorie restriction so late in an animal's life could reduce the muscle changes that occur regularly with aging," said UW Medical School professor of medicine Richard Weindruch. "Age-associated muscle degeneration is seen in most mammals, including humans."
The new findings add to a growing body of evidence supporting significant age-retarding effects of a restricted yet nutritious diet. In addition to extending life span in many animals, calorie restriction (CR) slows down age-related deficits in behavior and learning, immune response, gene expression, enzyme activity, hormonal action, DNA repair capacity, glucose tolerance and rates of protein synthesis.
Weindruch, who co-authored the first text on dietary restriction, an in-depth review article in Scientific American and several reports in other prestigious journals, was the first to show that even starting rodents on a controlled diet in midlife produced longer-lived, healthier animals.
A researcher at the Geriatric Research, Education and Clinical Center at the William S. Middleton Veterans Hospital and UW-Madison, Weindruch and colleague Judd Aiken, associate professor of animal health and biomedical sciences, focused on skeletal muscle in their current study to determine how CR affects age-linked muscle mass loss. Known as sarcopenia, the condition is thought to contribute to physical frailty in older people.
"Laboratory studies by our team and others have shown that CR can
reduce the rate of skeletal muscle loss with age, but the exact mechanisms
have been unclear,"
Contact: Dian Land
University of Wisconsin-Madison