Effects of Vitamin E on Food Intake and Body Weight in Rats Exposed to Restraint Stress

Many investigators have shown that stress suppresses food intake and reduces body weight in rats. The effect of vitamin E on body weight and food intake in rats exposed to stress were studied. Male Sprague Dawley rats (n = 80) were fed with either normal chow, vitamin E deficient diet or vitamin E with or without oral supplementation of either tocopherol, tocotrienol or Tocomin at 60mg/kg body weight. The rats were treated with these different diet regimes for 28 days prior to exposure to stress. Repetitive stress was applied, whereby the rats were restrained 2 hours daily for 4 consecutive days. The body weight and food intake was measured, weekly and after exposure to stress. The findings showed that vitamin E deficiency induced by feeding rats with vitamin E deficient diet for 28 days resulted in significantly lower body weight and food intake compared to the control animals given (normal chow). Supplementation with vitamin E in different forms, tocopherol, tocotrienol or Tocomin to the deficient diet was unable to increase the body weight or food intake, where both parameters were comparable with rats fed with deficient diet alone. It is possible that the dose of the vitamin E given was inadequate to maintain the food consumption and prevent the drop in body weight. Exposure to stress caused a further reduction in both the food intake and body weight in all groups and this suggests that the normal level of vitamin E in normal chow nor the supplementation with tocopherol and tocotrienol at the dose 60mg/kg was able to protect against changes in the body weight and food intake due to stress. We therefore conclude that vitamin E deficiency and stress can reduce food intake and cause a reduction in body weight. Stress can worsen the status of the two parameters and in vitamin E supplementation at 60 mg/kg body weight is not sufficient to prevent the changes in the body weight or food intake due to vitamin E deficiency or stress.