Calorie Restriction Enhances Longevity Without Reducing Lifetime Fecundity or Glucose Titers in Female Lubber Grasshoppers

Calorie restriction, under eating while avoiding malnutrition, enhances longevity in many organisms, in part by delaying fecundity or lowering blood glucose. Calorie restriction begun at middle-age can also enhance longevity. We tested four diets on longevity of female lubber grasshoppers: ad libitum (free access to food), calorie restriction (60% or 71% of ad libitum), and delayed calorie restriction (60% after day 50). Constant calorie restriction increased longevity in grasshoppers by at least 66%. These diets lowered body mass, but it did not reduce lifetime fecundity or chronically lower blood glucose levels. Calorie restriction reduced the levels of stored protein after egg laying. Delayed calorie restriction also increased longevity (also by 66%), but because the body mass gain of this group did keep pace with ad libitum grasshoppers when they were fed identically, this result needs retesting. These extensions of lifespan likely are due to slowed aging