Vitamin E Health Article

Preparations

The U.S. recommended dietary allowance (RDA) of the alpha-tocopherol formulation of vitamin E is as follows:

• men: 10 mg or 15 IU
• women: 8 mg or 12 IU
• pregnant women: 10 mg or 15 IU
• lactating women: 12 mg or 18 IU

In April 2000, the National Academy of Sciences recommended changing the RDA for vitamin E to 22 international units (IUs), with an upper limit (UL), or maximum daily dose, of 1500 IUs. Daily values for the vitamin as recommended by the U.S. Food and Drug Administration, the values listed on food and beverage labeling, remain at 30 IUs for both men and women age four and older.

Many nuts, vegetable-based oils, fruits, and vegetables contain vitamin E. Foods rich in vitamin E include wheat germ oil (26.2 mg/tbsp), wheat germ cereal (19.5 mg/cup), peanuts (6.32 mg/half cup), soybeans (3.19 mg/cup), corn oil (2.87/tbsp), avocado (2.69 mg), and olive oil (1.68 mg/tbsp.). Grapes, peaches, broccoli, Brussels sprouts, eggs, tomatoes, and blackberries are also good sources of vitamin E. Fresh, raw foods contain the highest levels of the vitamin. Both heat and light can reduce vitamin and mineral potency in fresh foods, so overcooking and improper storage should be avoided. Sliced and chopped foods have more of their surface exposed to light, therefore keeping vegetables and fruits whole may also help to maintain full vitamin potency.

For individuals considered at risk for vitamin E deficiency, or those with an inadequate dietary intake, vitamin E supplements are available in a variety of different forms, including pills, capsules, powders, and liquids for oral ingestion. For topical use, vitamin E is available in ointments, creams, lotions, and oils. Vitamin E is also available commercially as one ingredient of a multivitamin formula.

The recommended daily dosage of vitamin E varies by individual need and by the amount of polyunsaturated fats an individual consumes. The more polyunsaturated fats in the diet, the higher the recommended dose of vitamin E, because vitamin E helps to prevent the oxidizing effects of these fats. Because vitamin E is fat soluble, supplements should always be taken with food.

Supplements are also available in either natural or synthetic formulations. Natural forms are extracted from wheat germ oil and other vitamin E food sources, and synthetic forms are extracted from petroleum oils. Natural formulas can be identified by a d prefix on the name of the vitamin (i.e., d-alpha-tocopherol).

Precautions

Overdoses of vitamin E (over 536 mg) can cause nausea, diarrhea, headache, abdominal pain, bleeding, high blood pressure, fatigue, and weakened immune system function.

Patients with rheumatic heart disease, iron deficiency anemia, hypertension, or thyroid dysfunction should consult their healthcare provider before starting vitamin E supplementation, as vitamin E may have a negative impact on these conditions.

Side effects

Vitamin E is well-tolerated, and side effects are rare. However, in some individuals who are vitamin K deficient, vitamin E may increase the risk for hemorrhage or bleeding. In some cases, side effects may be decreased or eliminated by adjusting the dosage of vitamin E and vitamin K.

Although the reasons are not yet clear, high intake of vitamin E has been associated with a statistically significant increased risk of breast cancer in men.

Vitamin E ointments, oils, or creams may trigger an allergic reaction known as contact dermatitis. Individuals who are considering using topical vitamin E preparations for the first time, or who are switching the type of vitamin E product they use, should perform a skin patch test to check for skin sensitivity to the substance. A small, dime sized drop of the product should be applied to a small patch of skin inside the elbow or wrist. The skin patch should be monitored for 24 hours to ensure no excessive redness, irritation, or rash occurs. If a reaction does occur, it may be in response to other ingredients in the topical preparation, and the test can be repeated with a different vitamin E formulation. Individuals who experience a severe reaction to a skin patch test of vitamin E are advised not to use the product topically. A dermatologist or other healthcare professional may be able to recommend a suitable alternative.