The Effect of Restricted Food Intake on the Life Span of Genetically Obese Mice

Abstract

Three groups of animals were used to determine the effect of restricted food intake on the longevity of hereditary obese mice. Obese mice in group I were fed ad libitum for life. Obese mice in group II were on limited food intake from 6 weeks of age for life and the thin sibling controls of group III, were allowed unlimited food. The maximum mean weight for animals in group I was 83 gm, for animals in group II, 36 gm and for group III, 30 gm. The body weight associated with longer life span in genetically obese mice was in a range greater than that normally attained by non-obese controls but considerably less than that reached by obese mice allowed to eat ad libitum. The mean life span for obese mice fed ad libitum was 457 days, for restricted obese mice, 795 days and for the controls, 747 days. One hundred percent of the full-fed obese mice were dead by 667 days while 81% of the obese mice on limited food intake and 60% of the non-obese controls were still alive at 730 days. These results show that severe obesity resulting from overeating in animals whose genetic constitution favors overfeeding greatly shortens the life span of these animals.