Vitamin E is the collective family name for eight fat soluble compounds that together have many health benefits. The complete Vitamin E family is composed of- 4 forms of Tocopherols (alpha, beta, gamma and delta) and 4 forms of Tocotrienols (alpha, beta, gamma & delta). Each of the 8 forms of vitamin E has its own biological activity and function in the body. Because each form provides slightly different benefits it is therefore important to ideally consume all 8 types of vitamin E. The vast majority of Vitamin E supplement only contain one form of Vitamin E, mostly synthetic dl-alpha tocopherol, or the more preferred natural version d-alpha tocopherol. In order to get the full benefits of vitamin E; especially the benefits to the heart, it is important to get the best full spectrum Vitamin E supplement you can find.

The most important function of vitamin E is to maintain the integrity of the body's intracellular membrane by protecting its physical stability and providing a defense line against tissue damage caused by oxidation. Vitamin E is protective because it helps reduce oxidation of lipid membranes and the unsaturated fatty acids and prevents the breakdown of other nutrients by oxygen. Vitamin E is an antioxidant that prevents free radical damage in biological membranes. Free radicals can cause cell damage that may contribute to the development of cardiovascular disease and cancer. Vitamin E has an effect on several enzyme activities and membrane properties. It is involved in the regulation of vascular smooth muscle cell proliferation and protein kinase C activity. Vitamin E as an antioxidant helps to stabilize cell membranes and protect the tissues of the skin, eyes, liver, breast, and testes, which are more sensitive to oxidation. When applied to the skin, vitamin E-containing creams or oils are believed to promote healing, protecting cells from free-radical damage and reducing itchiness. Many people use such products to ensure optimal skin health. The protective, nutritional antioxidant function of vitamin E is also performed and enhanced by other antioxidants, such as vitamin C, beta-carotene, glutathione (L-cysteine), and the mineral selenium.

What is Vitamin E?

Vitamin E is a generic term for tocopherols and tocotrienols. Vitamin E is a family of α-, β-, γ-, and δ- (respectively: alpha, beta, gamma, and delta) tocopherols and corresponding four tocotrienols. Vitamin E is a fat-soluble antioxidant that stops the production of reactive oxygen species formed when fat undergoes oxidation. Of these, α-tocopherol (also written as alpha-tocopherol) has been most studied as it has the highest bioavailability.

Where is it Found?
Numerous foods provide vitamin E. Nuts, seeds, and vegetable oils are among the best sources of alpha-tocopherol, and significant amounts are available in green leafy vegetables and fortified cereals (see Table for a more detailed list). Most vitamin E in American diets is in the form of gamma-tocopherol from soybean, canola, corn, and other vegetable oils and food products.

Selected Food Sources of Vitamin E (Alpha-Tocopherol)

DV = Daily Value. The DV for vitamin E is 30 IU (approximately 20 mg of natural alpha-tocopherol) for adults and children age 4 and older.

Supplements of vitamin E typically provide only alpha-tocopherol, although "mixed" products containing other tocopherols and even tocotrienols are available. Naturally occurring alpha-tocopherol exists in one stereoisomeric form. In contrast, synthetically produced alpha-tocopherol contains equal amounts of its eight possible stereoisomers; serum and tissues maintain only four of these stereoisomers. Alpha-tocopherol in dietary supplements and fortified foods is often esterified to prolong its shelf life while protecting its antioxidant properties. The body hydrolyzes and absorbs these esters (alpha-tocopheryl acetate and succinate) as efficiently as alpha-tocopherol.

Vitamin E and heart disease - Vitamin E helps protect against heart disease by limiting the oxidation of LDL-cholesterol. Vitamin E helps prevent oxidation of lipoproteins, particularly in smokers, and reduces the stickiness of platelets in the bloodstream. Vitamin E also keeps arteries flexible and elastic, allowing blood to flow freely. Vitamin E helps prevent arteries from clogging by blocking the conversion of cholesterol into the waxy fat deposits called plaque that stick to blood vessel walls. Vitamin E also thins the blood, allowing for blood to flow more easily through arteries even when plaque is present. Vitamin E also may help prevent the formation of blood clots, which could lead to a heart attack. Vitamin C and vitamin E, taken in combination, help to stabilise LDL cholesterol in the body. This may help to reduce the risk of atherosclerosis.

Vitamin E and cancer - Some cancers are believed to result from oxidative damage to DNA caused by free radicals. Free radicals can damage DNA, leading to mutations in cells that may cause cancer. Antioxidants such as vitamin E help protect against the damaging effects of free radicals. The vitamin may also help fight cancer by boosting the immune system. Vitamin E may protect against the development of cancers by enhancing immune function. Some evidence associates higher intake of vitamin E with a decreased incidence of prostate cancer and breast cancer. Cigarette smokers have a higher risk of developing cancers of the mouth, upper airways and lungs, and vitamin E may help protect smokers against these cancers through its antioxidant properties.

Vitamin E and cataracts - Because of its antioxidant action, vitamin E may help to protect against cataracts and age related macular degeneration. Cataracts are growths on the lens of the eye that cloud vision. They increase the risk of disability and blindness in aging adults. Lens clarity, which is used to diagnose cataracts, is better in regular users of vitamin E supplements and in persons with higher blood levels of vitamin E. Uveitis is another eye disorder for which the antioxidant vitamins C and E may be helpful. Uveitis is inflammation of the uvea, the middle layer of the eye between the sclera and the retina.

Vitamin E and Alzheimer's disease - Alzheimer's disease is a wasting disease of the brain. Oxidative stress is believed to contribute to the development of Alzheimer's disease. Vitamin E is an antioxidant that prevents free radical damage in biological membranes. Vitamin E supplementation improves cognitive performance in healthy individuals and in those with dementia from causes other than Alzheimer's disease. In addition, vitamin E, together with vitamin C may prevent the development of Alzheimer's disease.

When To Take / Type to takeDosage
Vitamin E dosing can be extremely confusing, since there are different ways to measure vitamin E content. Although current recommendations use milligrams (mg), most supplements still use international units (IU). Converting between mg and IU is not straightforward, since natural vitamin E (RRR-alpha-tocopherol, historically known as d-alpha-tocopherol) is more active than synthetic vitamin E (all-rac-alpha-tocopherol, historically known as dl-alpha-tocopherol). The synthetic form contains several different "isomers," some of which do not contribute to the daily requirement of vitamin E. As a result, it takes more dl-alpha-tocopherol than d-alpha-tocopherol (in terms of IU) to meet the daily requirements.

The Institute of Medicine (IOM) has established an RDA (recommended dietary allowance) for vitamin E (given in mg of alpha-tocopherol, a measure that takes into account only certain forms of alpha-tocopherol). Refer to the following table for RDA values for vitamin E doses, along with the conversions for IU for different forms of vitamin E:

Vitamin E supplements are best taken with a meal. Research has shown a combination of alpha-, beta-, and delta tocopherol together (aka, “mixed tocopherols”) is more effective than alpha-tocopherol alone. For eg. In one study a mixture of these tocopherols was shown to have a stronger effect at inhibiting free radical damage to human blood cells than alpha-tocopherol alone. In another study, the combination of tocopherols were shown to have a synergistic (I,e enhancing) effect in inhibiting platelet aggregation, or the clumping together of blood cells, above and beyond the effect of the individual tocopherols. The prevention of platelet clumping is important since such clumping can be a contributory factor toward certain types of cardiovascular disease.

To stabilize Vitamin E for inclusion in some supplements, it is combined with (chelated to ) either of two organic acids, acetic acid or succinic acid, to create d-alpha tocopheryl acetate or d-alpha tocopheryl succinate. The “O” in tocopherol is then changed to a “y” to designate that it has been chelated with an organic acid.

Possible Side-Effects / Precautions / Possible Interactions
High doses have also been reported to cause (or may theoretically cause) the following vitamin E side-effects such as:
Nausea
Diarrhea
Intestinal cramping
Fatigue and weakness
Headaches
Blurred vision
Any unusual bruising or bleeding (vitamin E can increase the risk of bleeding)

Signs of gastrointestinal bleeding, such as black, tarry stools, bright-red blood in the stool, and vomiting of blood. Some people may experience irritation or allergic reactions when vitamin E is applied to the skin.

Interactions with Medications
People taking these and other medications on a regular basis should discuss their vitamin E intakes with their healthcare providers.

Anticoagulant and antiplatelet medications
Vitamin E can inhibit platelet aggregation and antagonize vitamin K-dependent clotting factors. As a result, taking large doses with anticoagulant or antiplatelet medications, such as warfarin (Coumadin®), can increase the risk of bleeding, especially in conjunction with low vitamin K intake. The amounts of supplemental vitamin E needed to produce clinically significant effects are unknown but probably exceed 400 IU/day [56].

Simvastatin and niacin
Some people take vitamin E supplements with other antioxidants, such as vitamin C, selenium, and beta-carotene. This collection of antioxidant ingredients blunted the rise in high-density lipoprotein (HDL) cholesterol levels, especially levels of HDL2, the most cardioprotective HDL component, among people treated with a combination of simvastatin (brand name Zocor®) and niacin [57,58].

Chemotherapy and radiotherapy
Oncologists generally advise against the use of antioxidant supplements during cancer chemotherapy or radiotherapy because they might reduce the effectiveness of these therapies by inhibiting cellular oxidative damage in cancerous cells [59,60]. Although a systematic review of randomized controlled trials has called this concern into question [61], further research is needed to evaluate the potential risks and benefits of concurrent antioxidant supplementation with conventional therapies for cancer.

Research Studies / References