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 Vitamin E is a group of fat-soluble essential vitamin chemical substances that are biologically and structurally similar to alpha-tocopherol. Vitamin E’s precise biochemical role is not yet known.
Vitamin E is suggested to provide protection against cancers and heart disease because of its antioxidant activities. Because of its immune-enhancing effects, it may provide limited benefits for those with rheumatoid arthritis and asthma. Vitamin E may provide protection against toxins such as air pollutions, premenstrual syndrome, eye disorders such as cataracts, neurological diseases such as Alzheimer’s disease, ultraviolet radiation, and diabetes. There is no proof to show that vitamin E enhances male fertility, sexual prowess, exercise performance, or in the reversal of skin aging. It may provide relief for muscle cramping.
Vitamin E helps the body process glucose. Some trials show that vitamin E might be helpful in treating and preventing diabetes.
Vitamin E has been used in those with the following health problems:
- Anemia (if deficient)
- Burns (in combination with vitamin C for prevention of sunburn only)
- Epilepsy (for children)
- Immune function (for elderly people)
- Intermittent claudication
- Rheumatoid arthritis
- Tardive dyskinesia
Suggested Dosage and Administration
The National Research Council has recently issued a report limiting vitamin E activity to only alpha-tocopherol, one of the homologues of the tocopherol family. Alpha-tocopherol only contains the naturally occurring form, RRR-alpha-tocopherol, frequently called d-tocopherol, and four out of the eight forms of synthetic alpha-tocopherol called all rac-alpha-tocopherol, frequently referred to as d1-alpha-tocopherol. The four forms included are RRR-, RSR-, RRS- and RSS-alpha-tocopherol, the 2R structures. RRR-alpha-tocopherol, natural alpha-tocopherol (referred to as natural-source alpha-tocopherol commercially), has roughly twice the availability of the all-synthetic d1-alpha-tocopherol and is most likely the superior form of supplementation.
The RDA dosage for alpha-tocopherol is 15 milligrams daily for men and women. This includes natural-source or natural alpha-tocopherol. 30 milligrams daily of all rac-alpha-tocopherol are necessary to provide the RDA for the vitamin because only 4 of the 8 stereoisomers of the all rac-alpha-tocopherol have vitamin E activity.
Two conversion factors are used to determine the amount of alpha-tocopherols present in a supplement labeled in international units. Multiply IU times 0.67 if the forms are d-alpha-tocopherol, d-alpha-tocopheryl acetate or d-alpha-tocopheryl succinate. Multiply IU times 0.45 if the forms are d1-alpha-tocopherol, dl-alpha tocopheryl acetate or dl-tocopheryl succinate.
Those with vitamin E deficiency should consult a physician for the proper dose.
Recommended doses of vitamin E can vary from 100 to 400 milligrams each day. A maximum of 1000 milligrams each day is suggested for d-alpha-tocopherol in the form of d-alpha-tocopheryl acetate. 200 to 800 milligrams each day of succinate is recommended with a maximum allowed of 1000 milligrams each day for d1-alpha-tocopherol in the form of dl-alpha-tocopheryl acetate or succinate.
The average intake of alpha-tocopherol according to different dietary surveys varies from around 7.5 to 10.3 milligrams daily for men and 5.4 to 7.3 milligrams daily for women. These estimates could be low due to people underreporting their caloric and fat intake and because of questions about which fats or oils are consumed. An average daily intake of about 15 milligrams is believed to be closer to the truth. Gamma-tocopherol is the primary vitamin E form found in the American diet.
Stampfer MJ, Hennekens CH, Manson JE, et al. Vitamin E consumption and the risk of coronary heart disease in women. N Engl J Med 1993;328:1444–1449.
Zoler ML. Supplemental vitamin E linked to heart failure. Fam Pract News 2003 (October 1):28.
Knekt P, Heliovaara M, Aho K, et al. Serum selenium, serum alpha-tocopherol, and the risk of rheumatoid arthritis. Epidemiology 2000;11:402–405.
Hashim S, Sajjad A. Vitamin E in the treatment of tardive dyskinesia: a preliminary study over 7 months at different doses. Int Clin Psychopharmacol 1988;13:147–153.
Panel on Dietary Antioxidants and Related Compounds, Food and Nutrition Board, Institute of Medicine, National Academy of Sciences. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, D.C.: National Academy Press, 2000, 249–258.
Balz F. Antioxidant vitamins and heart disease. Presented at the 60th Annual Biology Colloquium, Oregon State University, Corvallis, Oregon, February 25, 1999.
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