Vitamin E
Vitamin E is a fat-soluble vitamin and an antioxidant vitamin involved in the metabolism of all cells. It protects vitamin A and essential fatty acids from oxidation in the body cells and prevents breakdown of body tissues.
Vitamin E is the term used for eight naturally occurring, fat-soluble nutrients called tocopherols - alpha, beta, gamma, delta, epsilon, zeta, eta and theta. Alpha-Tocopherol is essential, has the highest biological activity, and predominates in many species. The RDA for adults is 10 IU. (Designated according to its biological activity in International Units (IU). With this vitamin 1 IU = 1 mg Alpha Tocopherol Equivalents). In human beings, vitamin E is the most important fat-soluble antioxidant. It prevents the potentially harmful oxidation of fat compounds and enhances the functioning of vitamin A. It is an antipollutant for the lungs. It helps the healing of scar tissue when taken internally and also when applied externally.
The best natural sources are wheat germ, whole grains, vegetable oils, soya beans, nuts, apples, apricots and green vegetables.
Vitamin E deficiency may cause anemia, as a result of red blood cell destruction and neurological dysfunction, myopathies, and diminished erythrocyte life span. New clinical evidence from heavy drinkers suggests that alcohol may increase oxidation of Alpha-Tocopherol. Increased demand has also been observed in premature infants and patients with malabsorption. It is generally non toxic but some evidence suggests that large intakes may cause increased levels of blood cholesterol and lipids. It can oxidize within a few months of being manufactured, so supplements should not be stored for more than a few months. It is destroyed by heat, freezing, food processing, chlorine and iron.
Vitamin E supplements are usually sold as alpha-tocopheryl acetate, a form that protects its ability to function as an antioxidant. The synthetic form is labeled "D, L" while the natural form is labeled "D". The synthetic form is only half as active as the natural form. (U.S. Department of Agriculture, Agricultural Research Service. 2004. USDA National Nutrient Database for Standard Reference, Release 16-1. Nutrient Data Laboratory)
Antioxidants such as Vitamin E act to protect your cells against the effects of free radicals, which are potentially damaging by-products of energy metabolism. Free radicals can damage cells and may contribute to the development of cardiovascular disease and cancer. Studies are underway to determine whether vitamin E, through its ability to limit production of free radicals, might help prevent or delay the development of those chronic diseases. Vitamin E has also been shown to play a role in immune function, in DNA repair, and other metabolic processes.
(Source: Traber MG. Vitamin E. In: Shils ME, Olson JA, Shike M, Ross AC, ed. Modern Nutrition in Health and Disease. 10th ed. Baltimore: Williams & Wilkins, 1999:347-62. )
| Good Food Sources of Vitamin E |
| Food |
Serving Size |
Milligrams |
% RDA |
| Egg, whole, fresh |
1 large |
0.88 |
5.8 |
| Almond oil |
1 tablespoon |
5.3 |
35.3 |
| Corn oil |
1 tablespoon |
1.9 |
12.6 |
| Corn oil (Mazola) |
1 tablespoon |
3 |
5 |
| Cottonseed oil |
1 tablespoon |
4.8 |
32 |
| Olive oil |
1 tablespoon |
1.6 |
10.6 |
| Palm oil |
1 tablespoon |
2.6 |
17.3 |
| Peanut oil |
1 tablespoon |
1.6 |
10.6 |
| Safflower oil |
1 tablespoon |
4.6 |
30.6 |
| Soybean oil |
1 tablespoon |
1.5 |
10 |
| Sunflower oil |
1 tablespoon |
6.1 |
40.6 |
| Vegetable-oil spray |
2.5 second spray |
0.51 |
3.4 |
| Wheat-germ oil |
1 tablespoon |
20.3 |
135.3 |
| Tomato juice |
6 fluid ounces |
0.4 |
2.6 |
| Apple with skin |
1 medium |
0.81 |
5.4 |
| Mango, raw |
1 medium |
2.32 |
15.4 |
| Macaroni pasta, enriched |
1 cup |
1.03 |
6.8 |
| Spaghetti pasta, enriched |
1 cup |
1.03 |
6.8 |
| Almonds, dried |
1 ounce |
6.72 |
44.8 |
| Hazelnuts, dried |
1 ounce |
6.7 |
44.6 |
| Peanut butter (Skippy) |
1 tablespoon |
3 |
5 |
| Peanuts, dried |
1 ounce |
2.56 |
17 |
| Pistachio nuts, dried |
1 ounce |
1.46 |
9.7 |
| Walnuts, English |
1 ounce |
0.73 |
4.8 |
| Margarine (Mazola) |
1 tablespoon |
8 |
53.3 |
| Margarine (Parkay, diet) |
1 tablespoon |
0.4 |
2.6 |
| Mayonnaise (Hellmann’s) |
1 tablespoon |
11 |
73.3 |
| Miracle Whip (Kraft) |
1 tablespoon |
0.5 |
3.3 |
| Avocado, raw |
1 medium |
2.32 |
15.4 |
| Asparagus, frozen |
4 spears |
1.15 |
7.6 |
| Spinach, raw |
1/2 cup |
0.53 |
3.5 |
| Sweet potato |
1 medium |
5.93 |
39.5 |
| Tomato, red, raw |
1 tomato |
0.42 |
2.8 |
| Turnip greens, raw |
1/2 cup chopped |
0.63 |
4.2 |
An Institute of Medicine (IOM) report on vitamin E published in 2000 cautions that low fat diets can result in a significant decrease in vitamin E intake. (Source: Institute of Medicine, Food and Nutrition board. Dietary Reference Intakes: Vitamin C, Vitamin E, Selenium, and Carotenoids. National Academy Press, Washington, DC, 2000. )
Individuals who cannot absorb fat require a vitamin E supplement because some dietary fat is needed for the absorption of vitamin E from the gastrointestinal tract.
People who cannot absorb fat often pass greasy stools or have chronic diarrhea. People with an inability to secrete bile, a substance that helps fat digestion, may need a special water-soluble form of vitamin E. (Source: Farrell P and Roberts R. Vitamin E. In: Shils M, Olson JA, and Shike M, ed. Modern Nutrition in Health and Disease. 8th ed. Philadelphia, PA: Lea and Febiger, 1994:326-41.)
Vitamin E in the diet may help reduce the risk of some of the most common diseases, such as heart disease and Alzheimer’s disease. Normal cell function results in byproducts known as free radicals. Free radicals can "attack" other cell substances, causing damage to the cell wall, metabolic machinery, and genetic material (DNA). Cells have natural defenses against this damage, including the antioxidants vitamins C and E, but with age some of these defenses decline. Brain cell damage caused by free radicals may play a role in Alzheimer’s disease.
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