What is Vitamin E?
Vitamin E is a fat soluble vitamin, essential for health. It refers to a group of related compounds which includes tocopherols and tocotrienols. Good source of Vitamin E are vegetable oils, nuts and nut oil seeds, egg yolk, margarine, cheese, soya beans, wheat germ, oatmeal, avocados, olives, green leafy vegetables etc. Tocopherols are predominantly found in olive, sunflower, corn, soya beans oils, and tocotrienols are the major Vitamin E components of palm oil, barley and rice bran. In humans, only alpha-tocopherol is specifically selected and enriched by the liver and is therefore the most abundant in the human body.
Why is Vitamin E important?
Vitamin E is a well-known anti-oxidant and it has multiple biological roles in our body. It helps protecting cells from the damage caused by free radicals. Free radicals are compounds formed when our bodies convert the food we eat into energy. People are also exposed to free radicals in the environment from cigarette smoke, air pollution, and ultraviolet light from the sun. Body also needs Vitamin E to boost its immune system so that it can fight off invading bacteria and viruses. The daily recommended dietary allowance of Vitamin E for adults is 15 mg (22.4 International Units).
Symptoms of Vitamin E deficiency
Vitamin E needs some fat for the digestive system to absorb it. Hence, Vitamin E deficiency is mostly associated with certain diseases where fat is not properly digested or absorbed. Examples include Crohn's disease, cystic fibrosis, and certain rare genetic diseases such as abetalipoproteinemia and ataxia with Vitamin E deficiency (AVED).
Vitamin E deficiency can cause dry hair, hair loss, muscular weakness, slow tissue healing, leg cramps, peripheral neuropathy (weakness, numbness and pain, usually in hands and feet), ataxia (loss of full control of bodily movements), skeletal myopathy (muscle disease resulting into muscle weakness), retinopathy (impairment or loss of vision), and weakened immune response.
Role of Vitamin E
Vitamin E plays an important role in protecting cells against free radicals. It also plays a role in preventing oxidation of Vitamin A and C. Regeneration of the reduced form of vitamin C is a beneficial physiological effect of Vitamin E. Most common form of Vitamin E used for medicinal purpose is Tocopheryl Acetate. Vitamin E functions physiologically as a chain-breaking antioxidant that prevents the propagation of lipid peroxidation. Dietary intake of Vitamin E offers protection for DNA and proteins from oxidative damage.
Vitamin E is an integral part of the skin's antioxidant defenses, primarily providing protection against UV radiation and other free radicals that may come in contact with the epidermis(skin). Topical (external) Vitamin E offers multiple benefits:
- Helps in keeping skin soft and moisturized
- Protects against damage of Ultra Violet rays
- Decrease wrinkles of the skin
- UV protection helps protect against sunburn
How much Vitamin E is required?
Eating Vitamin E in foods is not risky or harmful. In supplement form, however, high doses of Vitamin E might increase the risk of bleeding (by reducing the blood's ability to form clots after a cut or injury) and of serious bleeding in the brain (known as haemorrhagic stroke). Because of this risk, the upper limit for adults is 1,500 IU/day for supplements made from the natural form of Vitamin E and 1,100 IU/day for supplements made from synthetic Vitamin E. The upper limits for children are lower than those for adults.
Side effects such as diarrhoea, intestinal cramps, angular stomatitis, lethargy and muscle weakness can occur after ingestion of large doses. These effects are known to be reversed after stopping Vitamin E administration.
Further Reading/ References
1. https://ods.od.nih.gov/factsheets/VitaminE-HealthProfessional/ accessed on 13-10-2016
2. Maria Laura Colombo. An Update on Vitamin E, Tocopherol and Tocotrienol - Perspectives. Molecules 2010, 15, 2103-2113.