Vitamin E

Other Name(s):

alpha tocopherol, alpha-tocopherol, tocotrienol, 5,7,8 trimethyl-tocotrienol

General Description:

Vitamin E is a series of fat-soluble compounds called tocopherols. Alpha-tocopherol is the most potent and widely used form of vitamin E. Tocopherols are found in the oily residue of plants. Tocotrienols are also found in plants and have vitamin E-like activity.

Vitamin E, vitamin C, and vitamin A are the antioxidant vitamins, and protect the body from oxidative damage.

Vitamin E is a major antioxidant in the body and works together with selenium to help prevent oxidation of certain enzymes important to the body's metabolic processes. Vitamin E is found in all cell membranes of the body and protects them from oxidative damage.

Vitamin E has been used when treating respiratory distress syndrome in premature infants. Its purpose is to protect their eyes from excess oxygen.

Medically Valid Uses:

Vitamin E prevents retrolental fibroplasia (disease of the retina) in premature infants on oxygen therapy. Vitamin E is a potent antioxidant in the human body.

Unsubstantiated Claims:

Please note that this section reports on claims that have NOT yet been substantiated through scientific studies.

Vitamin E is claimed to protect the body from environmental hazards and serve as an anti-cancer agent. It aids in the treatment of cystic fibrosis and breast disease, and helps with leg muscle pains and wound healing. Vitamin E is also claimed to be able to improve heart disease, help in sexual function, aid in athletic performance, facilitate scar healing and help to prevent Alzheimer's disease.

Recommended Intake:

Vitamin E is measured in both International Units (IU) and milligrams (mg), as indicated below. The DRI is the Dietary Reference Intake.

Vitamin E is sold primarily as a soft capsule for oral use. The strengths available range from 100 to 1,000 IU. It is also available as a chewable tablet and an oral solution. The strength of the oral solution is 50 mg/ml. Vitamin E oil is also available.

Vitamin E capsules should be swallowed whole. They should not be chewed.

Vitamin E is stable at room temperature and therefore does not need to be refrigerated. It is not destroyed by cooking. It remains active in foods that have been frozen.

Vitamin E is also stable in light and in the presence of acid and alkali. It occurs as a thick, yellowish oil.

An increased need for vitamin E may result from various malabsorption syndromes in which steatorrhea (excess fat in the stool) occurs. These syndromes include lactose intolerance, tropical and non-tropical sprue, celiac disease, cystic fibrosis, ulcerative colitis, pancreatitis and a pancreatectomy (removal of all or part of the pancreas).

Individuals need additional vitamin E if they are over 55, consume moderate to heavy amounts of alcohol, have chronic alcoholism or have liver diseases such as cirrhosis.

Women who are pregnant or breast-feeding may need to take vitamin supplements, but must consult a physician before doing so.

Symptoms of vitamin E deficiency in newborns include hemolytic anemia, retinopathy (disease of the retina) and edema. Low vitamin E status in adults has been associated with increased risk for atherosclerosis (hardening of the arteries), cancer, cataract formation and other aging processes in general.

Side Effects, Toxicity and Interactions:

Vitamin E is a relatively safe vitamin. Although vitamin E is fat soluble and can build up in the tissues of the body, hypervitaminosis is rare. Symptoms of too much vitamin E are fatigue, weakness, nausea, blurred vision, flatulence and diarrhea.

There are no known contraindications to vitamin E.

Vitamin E can increase the effects of oral anticoagulants (blood-thinning medications) and result in increased clotting time and bleeding.

Large doses of vitamin E can decrease the body's vitamin A reserves.

Additional Information:

Click here for a list of reputable Web sites with general information on nutrition.

References:

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