Innate function of Vitamin E
For almost a century, the biological role of vitamin E has been a scientific puzzle. Diets deficient in vitamin E lead to disease, specifically involving muscle, but the mechanism involved remained unsolved. Recent studies, reviewed here, show that vitamin E improves skeletal muscle cell survival after membrane injuries typically induced by exercise, namely by robustly promoting the rapid repair response a cell mounts to patch membrane tears. This capacity for repair promotion can explain why vitamin E is essential for muscle health. Understanding the biological function of vitamin E might provide the needed direction in the application of vitamin E as a beneficial supplement.
Animal cells are unable to synthesize vitamin E (1) and must therefore obtain it from exogenous sources. Healthy diets are generally rich in vitamin E-containing foods and, correspondingly, vitamin E deficiency in humans is a rare condition. The documented cases of vitamin E deficiencies in humans, although uncommon, typically are caused by diet-unrelated problems such a malabsorption diseases and liver cirrhosis (2). Nevertheless, vitamin E is a popular health and beauty product supplement, for example in body building formulas, skin creams and lotions, hair conditioners, power bars, weight loss formulas, multivitamins and even cold remedies. Whether this vitamin is an effective supplement, in most if not all such cases, has not been scientifically documented, to our knowledge.
DIETARY REQUIREMENT OF VITAMIN E
Vitamin E deficiencies lead to infertility and skeletal muscular disease
The discovery of vitamin E began in 1922 when rats failed to reproduce when fed a diet composed of the then known essential vitamins (3). When cotton seed oil was added to this diet, fertility was ...