Vitamin E and human health: rationale for determining recommended intake levels.
The recent literature provides strong evidence that vitamin E intakes much higher than the current recommendations can contribute to and/or improve human health. In fact, the available data indicate that at higher-than-current recommended intake levels, vitamin E affects several functions related to human health. For example, Vitamin E is required to protect polyunsaturated fatty acids (PUFAs) against auto-oxidation. The amount of vitamin E needed to protect PUFAs against oxidative damage is at least 0.4-0.8 mg vitamin E per gram PUFAs and may be in excess of 1.5 mg/g when diets contain higher-than-average levels of long-chain PUFAs. Based upon studies of vitamin E kinetics and metabolism, a daily vitamin E intake of 135-150 IU is suggested. Important functions such as protection against oxidative damage, immune response, and the propensity of platelets to adhere to the vessel wall are related to vitamin E intakes. Vitamin E intake of 40 IU/d was the least amount demonstrated to inhibit low-density lipoprotein oxidation; a dose-dependent effect was seen up to 800 IU/d. Vitamin E intakes of at least 60 IU/d enhanced immune responses and intakes of 200 IU-400 IU/d decreased platelet adhesion to the vessel wall. Based upon the effects of modulating these functions, it is hypothesized that vitamin E plays a pivotal role in the prevention of cardiovascular diseases. Indeed, many observational studies have reported vitamin E to reduce the risk of cardiovascular disease. Recent intervention studies corroborate these findings. Of equal importance, there is a solid body of literature that demonstrates that these and much higher vitamin E intakes are safe.
Weber
P
P
Human Nutrition Research Division, Hoffmann-La Roche, Paramus, New Jersey, USA.
Bendich
A
A
Machlin
L J
LJ
D002318:Cardiovascular Diseases / Q000209:etiology / Q000517:prevention & control; D004032:Diet; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007107:Immune System / Q000187:drug effects; D008297:Male; D009369:Neoplasms / Q000209:etiology / Q000517:prevention & control; D009751:Nutritional Requirements; D012449:Safety; D014810:Vitamin E / Q000008:administration & dosage* / Q000097:blood / Q000378:metabolism; D014811:Vitamin E Deficiency / Q000188:drug therapy / Q000209:etiology
D004042:Dietary Fats, Unsaturated; D005231:Fatty Acids, Unsaturated; D014810:Vitamin E