Vitamin E Factoids
Vitamin E Factoids
- Vitamin E is one of four fat-soluble vitamins. The other three are vitamins A, D, and K. Because it is fat-soluble, rather than water-soluble, it does not necessarily have to be included in the diet daily since the body can store it for later use. However, vitamin E is not stored as efficiently as the other fat-soluble vitamins. More than 90% of stored vitamin E can be found in adipose tissue.
- Vitamin E was first discovered in 1922 in lab studies with rats. Vitamin E was identified as an essential nutrient since rats could not reproduce in its absence. It was named vitamin E because it was the first vitamin to be discovered after vitamin D.
- Although vitamin E is regarded as a single vitamin, it actually contains eight components: alpha, beta, delta, and gamma tocopherol and alpha, beta, delta, and gamma tocotrienol. Of these, alpha-tocopherol is the component that has the most bioavailability and is the most abundant and active in the human body.
- Vitamin E acts as powerful antioxidant. One of its main functions is to inhibit the oxidation of free radicals that can cause damage to the cells. If left unchecked, oxidized free radicals hasten the aging process and increase the risk for serious health problems, including arthritis, Alzheimer’s disease, cataracts, heart disease, and cancer.
- Despite vitamin E being present in many foods, the typical American diet, which tends to be heavy in processed foods, does not contain enough vitamin E. The best food sources of vitamin E are wheat germ, nuts and seeds, peanut butter, cold pressed vegetable oils, whole grains, dark leafy vegetables, olives, legumes, and fortified cereals.
- Exposure to air and commercial food processing and certain cooking methods can cause significant depletion of a food’s vitamin E content. Commercial processing of wheat, which entails removing the germ layer and bleaching, destroys 50-90% of the original vitamin E content. Commercial processing of vegetable oils results in almost 2/3 of the vitamin E content being lost.
- Since vitamin E is fat-soluble rather than water-soluble, cooking in water is not a problem. However, roasting at high temperatures and deep fat frying will destroy much of the food’s vitamin E content.
- Vitamin E helps prevent atherosclerosis (hardening of the arteries). By acting as a blood thinner, vitamin E inhibits platelet clumping and unwanted blood clot formation. However, individuals who are already taking other types of blood thinners (such as warfarin or aspirin) need to check with their doctor before starting vitamin E supplements because otherwise they could run the risk of uncontrolled bleeding.
- Vitamin E may be useful in helping to prevent two potentially serious age-related diseases of the eye: cataracts and macular degeneration. Both of these disorders, if left untreated, can eventually cause blindness.
- Serious vitamin E deficiency is rare. Those who are at most risks for developing a severe vitamin E deficiency are premature infants with low birth weight, individuals with fat malabsorption disorders or other serious gastrointestinal disorders. Symptoms of vitamin E deficiency vary, but frequently include fatigue, muscle weakness, peripheral neuropathy (pain, tingling, and lack of sensation in the extremities), and poor muscle coordination. In severe cases, liver, kidney, and pituitary and adrenal gland malfunction may occur, along with retinopathy and hemolytic anemia.
- Despite the multiple contributions of vitamin E to normal body functioning and the many proposed medicinal uses for it, much of the published research findings on this vitamin to date fail to show the expected benefits. This is particularly true in studies regarding the purported ability of vitamin E to help prevent heart disease and cancer. Both individual differences and the likelihood of many other factors contributing are probably partly responsible for the inconsistent and frequently lackluster results. In any case, there is no evidence that high-dose supplementation of vitamin E is beneficial for the prevention of any condition in the absence of medical necessity, and it could be harmful.