Functions of Vitamin E
Example of vitamin E blocking the damage from free radicals
Vitamin E is not one vitamin, but a group of forms of the vitamin: α-, β-, γ-, and δ-tocopherol, α-, β-, γ-, and δ-tocotrienol. The body preferentially uses α-tocopherol, called alpha tocopherol. The main role of Vitamin E in the body is as an antioxidant. An antioxidant defends the body against oxidative damage. Oxidative damage is caused by free radicals. A free radical is a molecule which is produced by normal metabolism. It is very unstable and wants to combine with something, anything, to make itself stable. This could be proteins, DNA or lipids. When free radicals combine with these, damage occurs, called “oxidation” or “free radical damage”. In short, that damage can lead to a series of events (domino effect) that can cause chronic diseases, such as cancer. This is why we don’t want free radicals roaming our body inflicting damage!
Antioxidants combine with free radicals, and in a sense, neutralize them so that they cannot cause damage. This is called quenching. The fewer antioxidants that you have available to quench free radicals, the more your cells are susceptible to oxidative damage. In the diagram above, the free radical is starting a domino effect of damage, but vitamin E (the orange rectangle) blocks this domino effect, preventing further damage.
Antioxidants combine with free radicals, and in a sense, neutralize them so that they cannot cause damage. This is called quenching. The fewer antioxidants that you have available to quench free radicals, the more your cells are susceptible to oxidative damage. In the diagram above, the free radical is starting a domino effect of damage, but vitamin E (the orange rectangle) blocks this domino effect, preventing further damage.
Recommended Intake for Vitamin E
Age and Gender |
Amount of Vitamin per Day |
Infants 0-6 mo |
4 mg |
Infants 6-12 mo |
5 mg |
Children 1-3 yr |
6 mg |
Children 4-8 yr |
7 mg |
Children 9-13 yr |
11 mg |
Teenagers 14-18 yr |
15 mg |
Adults 19 and up |
15 mg |
Food Sources of Vitamin E
Vitamin E is widespread in foods, mostly occurring in fruits and vegetables and whole grains. Vegetable and seed oils are the best source. Most of these oils listed are highly processed oils and although high in vitamin E, they should be minimized in the diet. Olive is a good source of vitamin E and cold pressed EVOO (extra virgin olive oil) is a good source.
Oils |
Whole Food |
Olive oil (EVOO) |
almonds |
Sunflower oil |
hazelnuts |
Safflower oil |
peanuts/peanut butter |
Grapeseed oil |
apricots |
Canola oil |
avocados |
Corn oil |
trout |
Soybean oil |
spinach |
Wheat germ oil |
asparagus |
Vitamin E is readily destroyed by heat and processing, which means most of oil sources listed above are not good sources of vitamin E if you are using them to cook.
Vitamin E Video
|
|
|
References
- Vitamin E. Linus Pauling Institute. Micronutrient Information Center. Last accessed March 19, 2016. http://lpi.oregonstate.edu/mic/vitamins/vitamin-E
- Dietary Reference Intakes (DRIs): Recommended Dietary Allowances and Adequate Intakes, Vitamins. Food and Nutrition Board, Institute of Medicine, National Academies. United States Department of Agricultural. Last accessed April 1st, 2016. https://fnic.nal.usda.gov/sites/fnic.nal.usda.gov/files/uploads/recommended_intakes_individuals.pdf
- Header image by Lynn Hayes on FlickrCC, CC BY 2.0.
- Vitamin E as an antioxidant image created by Christine Dobrowolski
Last updated April 2nd, 2016