Tell me about...
Vitamin E
What is
vitamin E?
Also known as tocopherol or alpha-tocopherol, vitamin E is
a fat-soluble vitamin stored in the liver. It is one of three
vitamins which also act as antioxidants.
Why do
we need it?
In its role as an antioxidant, vitamin E helps neutralize
unstable particles called free radicals which damage cell
membranes. It also inhibits the oxidation of LDL cholesterol
("bad" cholesterol), which may reduce the risk of
arterial plaque buildup, stroke and heart attacks. In addition,
vitamin E plays an important function in the formation of
red blood cells and the use of vitamin K. Some studies have
shown that vitamin E may raise one's resistance to infectious
diseases and protect against cataracts.
How much
vitamin E should I take?
According to the National Academy of Sciences, the recommended
daily allowance for vitamin E (alpho-tocopherol) is as follows:
- Adult men: 10 milligrams/day
- Adult women: 8 milligrams/day
- Children aged 7-10: 7 milligrams/day
- Infants: 4 milligrams/day
- Pregnant/lactating women: 12 milligrams/day
In addition to the NAS guidelines, some groups recommend
much higher doses (between 70-130 milligrams/day).
What are
some good sources of vitamin E?
Vitamin E is found in vegetable oils (most notably wheat
germ oil), sweet potatoes, avocados, nuts, sunflower seeds
and soybeans. Smaller amounts are found in egg yolks and green
leafy vegetables.
What can
happen if I don't get enough vitamin E?
Deficiencies of vitamin E have been linked to heart disease.
People with extremely low blood levels of vitamin E may be
also be at higher risk for cancer.
What can
happen if I take too much?
Some people taking massive amounts of vitamin E have reported
experiencing fatigue, nausea and diarrhea. Too much vitamin
E may also cause bleeding problems, particularly in people
taking anti-clotting medications.
Other Resources :
The
More You Know About Vitamins
The
More You Know About Nutrition
References
• Horwitt MK.
Therapeutic uses of vitamin E in medicine. Nutrition Reviews
March 1980;38(3):105–113.
• Horwitt MK. Data supporting supplementation of humans
with vitamin E. Nutrition 1991;121:424–29.
• Rimm EB, Stampfer MJ, Ascherio A, et al. Vitamin E
consumption and the risk of coronary heart disease in men.
N Engl J Med 1993;328:1450–56.
• 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;328:1444–49.
• Stephens NG, Parsons A, Schofield PM, et al. Randomised
controlled trial of vitamin E in patients with coronary disease:
Cambridge Heart Antioxidant Study (CHAOS). Lancet 1996;347:781–86.
• Christen S, Woodall AA, Shigenaga MK, Southwell-Keely,
Duncan MW, Ames BN. Gamma-tocopherol traps mutagenic electrophiles
such as NO+ and complements alpha-tocopherol: physiological
implications. Proc Natl Acad Sci 1997;94:3217–22.
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