A Clue to Living Longer
Growth hormone and insulin may explain why restricting calories boosts longevity

SOURCE: "Targeted Disruption of Growth Hormone Receptor Interferes with the Beneficial Actions of Calorie Restriction" M. S. Bonkowski et al.Proceedings of the National Academy of Sciences 103(20): 7901-7905

RESULTS: Scientists at the Southern Illinois School of Medicine discovered that mice engineered to be resistant to growth hormone have a longer life span than normal mice; the increase is similar to that seen in normal mice fed a diet low in calories, but engineered mice fed a low-calorie diet showed no additional gain in longevity. Both the engineered mice and the calorie-restricted normal mice were much more sensitive to insulin, suggesting a possible mechanism for the increase in longevity.