what is vitamin E good for

Vitamin E is actually a collective term for a group of vitamins that play antioxidant roles in the body, meaning they neutralize free radicals that can cause damage. What is vitamin E good for, and what does it do?

What is vitamin E?

There are eight forms of vitamin E: alpha, beta, gamma, and delta tocotrienol, as well as alpha, beta, gamma, and delta tocopherol.  However, alpha tocopherol is the only form that humans need to ingest to meet their dietary needs.

This vitamin is an essential vitamin, which means that it is not made in the body and it must be obtained through the diet.  It is also a fat-soluble vitamin, which means that it can be stored in the body for extended periods of time and it is not excreted out of the body as quickly as a water-soluble vitamin. 

Where is it found?

Many foods contain vitamin E; some foods high in this vitamin include nuts, seeds, vegetable oils, green leafy vegetables, and fortified cereals.  In particular, these foods are high in alpha tocopherol.  Gamma tocopherol, which is converted to alpha tocopherol in the body, can be found in vegetable oils including corn, soybean, and canola oil.

Vitamin E can also be found in supplements; alpha tocopherol supplements are available, and it can sometimes be found in multivitamin supplements. This vitamin is transferred through breast milk when the mother has adequate intake, and commercial infant formulas are generally fortified with this vitamin.

Why is it important?

Vitamin E functions as an antioxidant, which means that it neutralizes the production of free radicals.  Free radicals are potentially harmful compounds that come from the molecules with reactive oxygen species produced by day-to-day life.  Reducing the effects of these free radical compounds could potentially help prevent damage to the cells and tissues from everyday activities.

It also helps protect the cell membranes, which is the lining that surrounds the cells and acts as a barrier.  It does this by preventing the oxidation of membrane phospholipids, which make up the majority of the cell membrane.

What is the RDA for vitamin E?

The RDA is 15mg daily for adults and teenagers over the age of 14, and 19mg daily for lactating women.  The RDA for is 11mg for children between nine and thirteen years of age, 7mg for children between four and eight years of age, 6mg for toddlers between one and three years of age, 5mg for infants between seven and twelve months, and 4mg for infants under seven months of age.

These values are given by the National Institutes of Health, and the RDA represents the daily intake sufficient to meet the dietary needs of 97-98% of healthy individuals.  There are many ways to meet this RDA through food or supplementation; one tablespoon of wheat germ oil has 135 percent of the RDA, and one ounce of dry-roasted sunflower seeds has 49 percent of the RDA.

How much is too much?

Since vitamin E is a fat-soluble vitamin, toxicity is possible as it is not easily excreted from the body like a water-soluble vitamin. The Upper Limit (UL) given by the National Institutes of Health represents the maximum daily intake unlikely to cause adverse health effects.

The UL is 1,000 mg daily for adults and 800 mg for teenagers between 14 and 18 years of age.  The UL is 600 mg for children between nine and thirteen years of age, 300 mg for children between four and eight years of age, and 200 mg for children between one and three years of age.  The UL for infants has not yet been established.

Although there is no current evidence that suggests that consuming large amounts of vitamin E from food can result in adverse health effects, there is a possibility that consuming excess through supplements could increase the risk of some side effects.  Two different studies show that taking these supplements was associated with an increased risk of hemorrhagic stroke in males.  Moreover, some scientists believe that taking large doses of supplemental vitamin E could inhibit blood clotting; however, this data is inconclusive as this was found from an in-vitro experiment not tested in the body.  More research is needed to determine whether this is relevant.

In addition, vitamin E supplements can potentially interact with certain medications including anticoagulants, antiplatelet medications, simvastatin, and chemotherapy.  It is important to tell your doctor and pharmacist about any medications and supplements you are taking to prevent these interactions.

What are the benefits?

One study of almost 3000 elderly people found that people who consumed the highest intakes of this vitamin showed less cognitive decline than groups with smaller intakes.  However, these results were not replicated with other studies, so these results are inconclusive.  More research is needed to determine whether vitamin E is associated with a decreased severity of age-related cognitive decline.

A few sporadic studies found that higher intakes below the UL were associated with decreased rates of coronary heart disease, age-related macular degeneration, and cataracts; however, the evidence on this in other studies is inconclusive.  More research is needed to determine if vitamin E is potentially preventative against these conditions.

Vitamin E deficiency

Isolated vitamin E deficiency is rare in developed countries, but some people are at a greater risk of deficiency than others due to different conditions.  Premature babies could potentially be at an increased risk of deficiency due to low birth weight.  This should be monitored by a doctor to determine the best course of treatment.

Since vitamin E is a fat-soluble vitamin and needs dietary fat to be absorbed most efficiently, people with fat-malabsorption disorders are at a greater risk of deficiency.  These conditions include cystic fibrosis and Crohn’s disease, among others.  For these conditions, water-soluble forms of vitamin E supplements are available, such as tocopherol polyethylene glycol-1000 succinate.

Vitamin E deficiency can be characterized by symptoms of ataxia, skeletal myopathy, retinopathy, and impaired immune response.  It can also increase the risk of degradation of red blood cells and nerve cells.

Vitamin E supplementation

Vitamin E deficiency is typically treated by supplements, taken either orally or by injection.  This deficiency can also be prevented by taking supplements or meeting your nutritional needs through your diet.

If you think you have a vitamin E deficiency or are at an increased risk, consider getting your blood levels tested.  As always, consult your doctor before you begin taking any vitamin or mineral supplement, to make sure your medications or health conditions don’t make it a serious risk.

References:

Morris, M.C., Evans, D.A., Bienias, J.L. (2002). Vitamin E and cognitive decline in older persons. Arch Neurol, 59(7), 1125-1132. Doi: 10.1001/archneur.59.7.1125

Office of Dietary Supplements – Vitamin E. (2020, July 31). Retrieved November 12, 2020, from https://ods.od.nih.gov/factsheets/VitaminE-HealthProfessional/

Rizvi, S., Raza, S.T., Ahmed, F., et al. (2014). The Role of Vitamin E in Human Health and Some Diseases. Sultan Qaboos University Medical Journal, 14(2), 157-165.

Vitamin E Deficiency By Larry E. Johnson, By, Johnson, L., & Last full review/revision Aug 2019| Content last modified Aug 2019. (n.d.). Vitamin E Deficiency – Nutritional Disorders. Retrieved November 12, 2020, from https://www.msdmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/vitamin-e-deficiency

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