ST. LOUIS, June 1 (UPI) -- Calorie restriction appears better than exercise at slowing primary aging, say researchers at the Washington University School of Medicine in St. Louis.
Dr. Luigi Fontana, assistant professor of medicine at Washington University in St. Louis and an investigator at the Istituto Superiore di Sanita in Rome, found that eating a low-calorie yet nutritionally balanced diet lowers concentrations of a thyroid hormone called triiodothyronine, or T3, which controls the body's energy balance and cellular metabolism.
"These findings suggest that although exercise helps prevent problems that can cut life short -- such as obesity, diabetes and cardiovascular disease -- only CR appears also to have an impact on primary aging."
For the new study, researchers examined 28 members of the Calorie Restriction Society who had been eating a CR diet for an average of six years. They eat an average of about 1,800 per day but consume at least 100 percent of the recommended daily amounts of protein and micronutrients.
Another 28 study subjects ate a standard Western diet and were sedentary. A third group ate a standard Western diet -- approximately 2,700 calories per day -- but did endurance training.
The study, published online in the Journal of Clinical Endocrinology and Metabolism, found reduced T3 levels only in the people on CR diets.
