Vitamin E
Vitamin E is a fat-soluble vitamin. Fat-soluble vitamins are stored in the liver and fatty tissues. There are eight different forms of vitamin E, and each has its own biologic activity. Alpha-tocopherol is the most active form of vitamin E in humans. It is an antioxidant—a substance that acts to protect the body's cells against the effects of free radicals. Free radicals are normal by-products of metabolism, but they can cause cell damage.
Functions
Vitamin E's functions include:
- Acting as an antioxidant in the body
- Maintaining the integrity of cell membranes
- Helping with immune system function
Recommended Intake:
Age Group | Recommended Dietary Allowance | |
---|---|---|
Females | Males | |
1-3 | 6 milligrams (mg) | 6 mg |
4-8 | 7 mg | 7 mg |
9-13 | 11 mg | 11 mg |
14-18 | 15 mg | 15 mg |
14-18 lactation | 19 mg | n/a |
19+ | 15 mg | 15 mg |
19+ lactation | 19 mg | n/a |
Vitamin E Deficiency
Symptoms of vitamin E deficiency include:
- Neurologic symptoms, such as impaired balance and coordination
- Muscle weakness
- Anemia
- Retinal degeneration (thinning of the lining of the inner eye)
Those occur mostly in areas of the world with very poor diets. In developed countries, vitamin E deficiency is seen only in certain conditions.
Vitamin E Toxicity
As a fat-soluble vitamin, vitamin E is stored in the body and not excreted in the urine like most water-soluble vitamins. Therefore, it is possible for vitamin E to accumulate in the body and reach toxic levels. The tolerable upper intake level (UL) for vitamin E from dietary sources and supplements combined is 1,000 milligrams. Symptoms of toxicity include:
- Muscle weakness
- Fatigue
- Double vision
- Nausea, diarrhea , gas
Major Food Sources
Food | Serving size |
Vitamin E content
milligrams (mg) |
---|---|---|
Wheat germ oil | 1 tablespoon | 27.0 |
Sunflower seeds, dry roasted | 1 ounce | 14.3 |
Sunflower oil | 1 tablespoon | 7.1 |
Hazelnuts, dry roasted | 1 ounce | 6.8 |
Tomato puree, canned | 1 cup | 6.3 |
Safflower oil | 1 tablespoon | 6.0 |
Almond oil | 1 T | 5.5 |
Wheat germ, toasted | 1/4 cup | 5.3 |
Papaya | 1 medium | 3.4 |
Peanut butter, creamy | 2 tablespoon | 3.2 |
Corn oil | 1 tablespoon | 3.0 |
Canola oil | 1 tablespoon | 2.9 |
Avocado | 1 medium | 2.3 |
Mango, raw | 1 medium | 2.3 |
Peanuts, dry roasted | 1 ounce | 2.1 |
Almonds, dry roasted | 1 ounce | 1.6 |
Blueberries | 1 cup | 1.5 |
Broccoli, boiled | 1/2 cup | 1.3 |
Pumpkin, canned | 1/2 cup | 1.3 |
Health Implications
Populations at Risk for Vitamin E Deficiency
The following populations may be at risk for vitamin E deficiency and may require a supplement:
- People with a reduced ability to absorb dietary fat—Because vitamin E is a fat-soluble vitamin, fat is required for its absorption. Some conditions that can cause fat malabsorption include Crohn's disease , cystic fibrosis , celiac disease , pancreatic enzyme deficiency, and liver disease.
- Very low birth weight infants—These infants are usually under the care of a neonatologist, who will evaluate and treat the premature infant's exact nutrition needs.
- People who suffer from abetalipoproteinemia—This is a rare inherited disorder of fat metabolism that results in poor absorption of dietary fat and vitamin E.
- Patients on dialysis
- Patients on chronic parenteral nutrition
- Patients after gastric bypass surgery
Antioxidant Capabilities
Free radicals are normal by-products of metabolism, but they can cause chain reactions that result in significant cell destruction. This cell destruction can, in turn, increase the risk for chronic diseases, including certain forms of cancer. Antioxidants have the ability to stop this chain reaction. Vitamin E functions in the body as an antioxidant. Because of this antioxidant capability, vitamin E is being studied for a possible role in chronic disease prevention.
It appears that vitamin E may protect against coronary artery disease. In addition, it is claimed to be useful in inflammatory diseases, such as arthritis, and in the prevention of some forms of cancer. But, only one study found a decrease in risk for prostate cancer with vitamin E supplementation in a population of male smokers . Definitely, more research is needed in this area.
Tips for Increasing Your Vitamin E Intake:
To help increase your intake of vitamin E:
- Sprinkle wheat germ on your cereal or oatmeal.
- Add sunflower seeds or nuts to a salad or stir-fry.
- Slice mangos or drop blueberries into yogurt for an afternoon snack.
- If you take a vitamin supplement, make sure it contains vitamin E.
RESOURCES:
American Dietetic Association
http://www.eatright.org/
United States Department of Agriculture
http://www.usda.gov/wps/portal/usdahome/
CANADIAN RESOURCES:
Canadian Council on Food and Nutrition
http://www.ccfn.ca/
Dietitians of Canada
http://www.dietitians.ca/
References
Duyff RL. The American Dietetic Association's Complete Food & Nutrition Guide. 3rd ed. Hoboken, NJ: John Wiley & Sons, Inc; 2006.
Facts about dietary supplements. National Institutes of Health website. Available at: http://www.nih.gov .
Food and Nutrition Information Center, US Department of Agriculture website. Available at: http://fnic.nal.usda.gov/nal_display/index.php?tax_level=1&info_center=4 .
Garrison RH, Somer E. The Nutrition Desk Reference. New Canaan, CT: Keats Publishing; 1995.
Heinonen OP, Albanes D, Virtamo J, et al. Prostate cancer and supplementation with alpha-tocopherol and beta-carotene: incidence and mortality in a controlled trial. J Natl Cancer Inst. 1998;90:440.
Mottram P, Shige H, Nestel P. Vitamin E improves arterial compliance in middle-aged men and women. Atherosclerosis. 1999;145:399.
Last reviewed February 2009 by Maria Adams, MS, MPH, RD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
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