Alternative Names tocopherol, alpha-tocopherol, tocotrienol
Definition Vitamin E is a fat-soluble vitamin. This means that it is dissolved in fat. Vitamin E attaches to fat. This is how it is carried through the body. This is one reason why moderate amounts of fat are needed in the diet. The body can store fat-soluble vitamins. Vitamin E has strong antioxidant properties. The vitamin may protect against heart disease and cancer. Its protective role has been widely studied. Vitamin E is part of a group of substances called tocopherols. Each group has different potencies.
What food source is the nutrient found in? Vitamin E is found in the fatty parts of foods. The best sources of vitamin E are unsaturated fats, such as vegetable oils. These include sunflower, safflower, olive, and wheat germ oils. It is also found in avocados, nuts, seeds, wheat germ, and whole grain, or unrefined, products. Fruit and vegetables have smaller amounts. Soybean oil has a form of vitamin E that has little influence on health. This oil is not a good source of vitamin E. Soybean oil is the most common oil used in products like salad dressing and mayonnaise. Heating oils to high temperatures, such as in frying, can destroy vitamin E. Storage and freezing foods for a long time can also destroy vitamin E.
Vitamin E is found in the germ of a seed or grain. Most of the nutrients are concentrated there. Whole-meal flour contains much of the original germ, so it has vitamin E. Refined flour, or white flour, has been stripped of many of its nutrients, including vitamin E.
How does the nutrient affect the body? Vitamin E is an important antioxidant. Antioxidants protect cells from oxidation. Oxidation can lead to cell damage. Cell damage can lead to chronic health problems, such as heart disease and cancer. Vitamin E works closely with other antioxidants, like vitamin C and selenium, to help protect the body. Vitamin E improves the way the body uses vitamin A. It may help protect against the toxic effects of some metals, such as lead.
Information The recommended dietary intake (RDI), for vitamin E is 10 milligrams (mg) daily for adult men and 7 mg for women. Pregnancy increases the recommendations slightly. Children's needs range from 8-11mg Vitamin E daily.
An upper level, based only on intake from vitamin supplements has been set at 200 - 1,000 mg of alpha-tocopherol. This is the most potent form of vitamin E. The upper level is not the recommended amount to take. The upper level is the maximum intake of a vitamin or mineral that is likely to cause no health risks. People should not routinely go above the set upper levels for vitamins and minerals. Taking too much vitamin E puts people at risk for prolonged bleeding time. This is because large doses can interfere with vitamin K. Vitamin K helps the blood to clot when a person is bleeding. Too much may also suppress the immune system. Not enough is known about vitamin E to make positive claims on mega doses, or extremely high doses of the vitamin. The question is if mega doses of antioxidants, such as vitamin E, can decrease the risk for chronic diseases. More research is needed.
Severe vitamin E deficiency is rare. Conditions where it may occur include people who don't absorb fat normally, premature infants, people with red blood cell disorders, and people on kidney dialysis. Symptoms of vitamin E deficiency include nerve damage and anaemia and blood disorders in infants.
To maximize vitamin E intake, healthy vegetable oils, nuts, seeds, and unrefined whole meal and whole-grain products should be a regular part of the diet.
Author: Kimberly Tessmer, RD, LD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
