context: Vitamin E is key for strong immunity and healthy skin and eyes. In recent years, vitamin E supplements have become popular as antioxidants. These are substances that protect cells from damage. However, the risks and benefits of taking vitamin E supplements are still unclear. Many people use vitamin E supplements in the hopes that the vitamin's antioxidant properties will prevent or treat disease. But studies of vitamin E for preventing cancer, heart disease, diabetes, Alzheimer's disease, cataracts, and many other conditions have been disappointing. So far, the only established benefits of vitamin E supplements are in people who have an actual deficiency. Vitamin E deficiencies are rare. They're more likely in people who have diseases, such as digestive problems and cystic fibrosis. People on very low-fat diets may also have low levels of vitamin E. The recommended dietary allowance ( RDA) includes the vitamin E you get from both the food you eat and any supplements you take. Category Vitamin E (alpha-tocopherol): Recommended Dietary Allowance ( RDA) in milligrams (mg) and International Units ( IU) CHILDREN 1-3 years 6 mg/day (9 IU) 4-8 years 7 mg/day (10.4 IU) 9-13 years 11 mg/day (16.4 IU) FEMALES 14 years and up 15 mg/day (22.4 IU) Pregnant 15 mg/day (22.4 IU) Breastfeeding 19 mg/day (28.5 IU) MALES 14 years and up 15 mg/day (22.4 IU) The tolerable upper intake levels of a supplement are the highest amount that most people can take safely. Higher doses might be used to treat vitamin E deficiencies. But you should never take more unless a doctor says so. Category ( Children & Adults) Tolerable Upper Intake Levels ( UL) of Vitamin E (alpha-tocopherol) in milligrams (mg) and International Units ( IU) 1-3 years 200 mg/day (300 IU) 4-8 years 300 mg/day (450 IU) 9-13 years 600 mg/day (900 IU) 14-18 years 800 mg/day (1,200 IU) 19 years and up 1,000 mg/day (1,500 IU) Because vitamin E is fat-soluble, supplements are best absorbed with food. Most people get enough vitamin E from food. Good sources of vitamin E include: Vegetable oils Green leafy vegetables, like spinach Fortified cereals and other foods Eggs Nuts The risks and benefits of taking vitamin E are still unclear. Long-term use (over 10 years) of vitamin E has been linked to an increase in stroke. In addition, an analysis of clinical trials found patients who took either synthetic vitamin E or natural vitamin E in doses of 400 IU per day -- or higher -- had an increased risk of dying from all causes, which seems to increase even more at higher doses. Cardiovascular studies also suggest that patients with diabetes or cardiovascular disease who take natural vitamin E at 400 IU per day have an increased risk of heart failure and heart failure-related hospitalization. Vitamin E supplements might be harmful when taken in early pregnancy. One study found that women who took vitamin E supplementation during the first 8 weeks of pregnancy had a 1.7 to nine-fold increase in congenital heart defects. The exact amount of vitamin E supplements used by pregnant women in this study is unknown. A large population study showed that men using a multivitamin more than seven times per week in conjunction with a separate vitamin E supplement actually had a significantly increased risk of developing prostate cancer. The American Heart Association recommends obtaining antioxidants, including vitamin E, by eating a well-balanced diet high in fruits, vegetables, and whole grains rather than from supplements. If you are considering taking a vitamin E supplement, talk to your health care provider first to see if it is right for you. What are the side effects of taking vitamin E? Topical vitamin E can irritate the skin. Overdoses of vitamin E supplements can cause nausea, headache, bleeding, fatigue, and other symptoms. People who take blood thinners or other medicines should not take vitamin E supplements without first talking to their health care provider.