Anti-aging nutritional supplementation and medicine

Much of anti-aging medicine has been concerned with the use of nutritional supplements to extend lifespan. The idea that antioxidant supplements, such as Vitamin C, Vitamin E, lipoic acid and N-acetylcysteine, might extend human life stems from the free radical theory of aging.
Other less popular hormones are oxytocin, insulin, human chorionic gonadotropin (hCG), erythropoietin (EPO), and others. Resveratrol is a sirtuin stimulant proposed to extend life in mammals in a similar manner to that claimed for calorie restriction in simple model organisms such as nematodes.[citation needed]
Some supplements have been shown to be of benefit against some aging-related disease conditions, or have extended average lifespan in animals, though none have been proven to do so in humans. Calorie restriction and supplementation with the minerals selenium, chromium and zinc ,have been shown to extend maximum lifespan in mice. Metformin,may also extend life span in mice, and in the first experiments with fish, resveratrol,looks promising. (Resveratrol is presently (2006) being tested in mice.)