Vitamin E is a fat-soluble vitamin found in many foods, fats, and oils. It is also an antioxidant. Antioxidants are substances that destroy free radicals -- harmful compounds in the body that damage DNA (genetic material) and even cause cell death. Free radicals are believed to contribute to aging as well as the development of a number of health problems, including heart disease and cancer. Antioxidants provide some protection against these conditions and also help reduce the damage caused by toxic chemicals and pollutants.

Vitamin E is also important in the formation of red blood cells and it helps the body to use vitamin K.

People who are unable to absorb fat properly may develop vitamin E deficiency. Symptoms of serious vitamin E deficiency include:

• Muscle weakness
• Loss of muscle mass
• Abnormal eye movements
• Impaired vision
• Unsteady gait

Chronic deficiency may also cause liver and kidney problems. Although most people in the United States aren’t seriously deficient in vitamin E, it’s not uncommon for people to be slightly deficient.

Heart Disease

Many population studies have found that people who have higher levels of vitamin E have a lower risk of heart disease. That led researchers to investigate whether taking vitamin E supplements might help prevent heart disease. But the results have not been promising.

One of the largest studies, the Heart Outcomes Prevention Evaluation (HOPE) trial, found that taking 400 IU of vitamin E (d-alpha-tocopherol) daily did not lower the number of heart attacks, strokes, or deaths from heart disease among men and women who already had heart disease or were at high risk for it.

What about otherwise healthy people who were at low risk for heart disease? Two large trials also found no protection from vitamin E. In one study (Physicians’ Health Study II) of more than 14,000 male doctors at low risk for cardiovascular disease, taking 400 IU of vitamin E every other day did not lower the risk of cardiovascular events or death over 8 years time.

One large clinical study suggested that vitamin E from foods may reduce the risk of death from stroke in postmenopausal women. The study results do not support the use of vitamin E supplements as part of a preventive strategy.

Cancer

Population studies (which involve observing large groups of people over time) suggest that eating foods high in vitamin E and other antioxidants may help prevent cancer. And studies have shown that people with cancer often have lower levels of vitamin E. Based on these observations, researchers theorized that antioxidants like vitamin E can help prevent cancer. But evidence about vitamin E supplements has not backed this up.

Several large clinical studies found that women who take vitamin E supplements do not have a lower risk of developing breast cancer. And one large study found that men who took 400 IU of vitamin E every other day for 8 years did not have a lower risk of overall cancer than those who took placebo.

Vitamin E also does not appear to protect against colorectal cancer in women or people with diabetes. There is some evidence that taking vitamin E along with vitamin A and vitamin C or as part of a multivitamin may offer some protection to people who had colorectal adenomas (considered to be precursors to colon cancer).

Vitamin E does not appear to offer any protection against lung cancer or pancreatic cancer.

The evidence about vitamin E and prostate cancer is mixed. Some population studies suggest that higher intakes of vitamin E is associated with a lower risk of prostate cancer. But not all population studies agree. One such study found that men who took a multivitamin more than 7 times per week along with a separate vitamin E supplement had an increased risk of prostate cancer.

One clinical trial found that taking a combination of 30 mg vitamin E (alpha-tocopherol), 120 mg vitamin C, 6 mg beta-carotene, 100 mcg selenium, and 20 mg zinc did not lower the overall risk of prostate cancer, but might reduce the risk in men whose PSA levels were normal. High PSA levels can indicate prostate cancer.

Another large study of 29,133 smokers found that those taking 50 mg daily of vitamin E (dl-alpha-tocopherol, or synthetic vitamin E) had a lower risk of prostate cancer and deaths caused by prostate cancer.

Researchers have also pointed to the fact that the body’s antioxidant defense system is complex, and taking antioxidant supplements may not have the same effect as getting them in your diet. Many experts believe getting antioxidants from foods may be the best way to protect against cancer.

Also, there is no evidence that taking large doses of vitamin E once diagnosed with cancer will help your treatment. In fact, there is concern that large doses of antioxidants from supplements could interfere with chemotherapy medications. Much more research in the area of antioxidants and cancer treatment is needed. If you are undergoing chemotherapy, talk to your doctor before taking vitamin E or any supplement.

Photodermatitis

This condition involves an allergic type reaction to the UV rays of the sun. An 8-day clinical study comparing treatment with vitamins C and E to placebo found that people who took the vitamins became significantly less sensitive to the sun. Another clinical study, lasting for 50 days, also showed a protective effect of the vitamin C and E combination.

Alzheimer’s Disease

Evidence is mixed as to whether vitamin E can help prevent or treat Alzheimer’s disease. Since researchers believe oxidative stress contributes to the development of Alzheimer’s disease, in theory antioxidants like vitamin E should help prevent it. But one study found that people who had early symptoms of Alzheimer’s and took vitamin E supplements went on to develop the disease at the same rate as those who took placebo.

In one study with positive results, 341 people with Alzheimer’s disease took either 2,000 IU of vitamin E (dl-alpha-tocopherol), the drug selegiline, or placebo. Those who were given vitamin E took about 200 days longer for the disease to progress to severe than those who took placebo. However, selegiline was more effective.

Eye Health

Vitamin E (400 IU) appears to work with other antioxidants including zinc (80 mg), beta-carotene (15mg), and vitamin C (500 mg) to protect against developing macular degeneration (AMD), the leading cause of legal blindness in people over 55 in the United States. The people who seem to benefit are those with advanced AMD. It isn't known whether this combination of nutrients helps prevent AMD or is beneficial for people with less advanced AMD.

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 (white outer coat of the eye) and the retina. A clinical study of 130 people with uveitis found that those who took these vitamins had clearer vision than those who took placebo.

Menstrual Pain

A few studies have found that vitamin E may help relieve menstrual pain or dysmenorrhea. In one study, taking 500 IU of vitamin E for 2 days before and 3 days after menstruation began reduced pain in young women better than placebo.

A few studies also suggest that vitamin E supplements may help reduce PMS symptoms, including anxiety, craving, and depression.

Diabetes

People with diabetes tend to have low levels of antioxidants, which has led some researchers to theorize that this might explain why they’re at increased risk for conditions such as cardiovascular disease. Vitamin E supplements and other antioxidants may help reduce the risk of heart disease and other complications in people with diabetes. Research shows that antioxidants may help control blood sugar levels and lower cholesterol levels in people with type 2 diabetes while protecting against the complications of retinopathy (eye damage) and nephropathy (kidney damage) in those with type 1 diabetes. One study found that people with type 2 diabetes who took 400 IU of vitamin E daily reduced their risk of heart attack and of dying from heart disease.

However, not all studies have found that taking vitamin E supplements helps people with diabetes. If you have diabetes, ask your doctor whether a vitamin E supplement would be right for you.

Pre-eclampsia

Some studies suggest that taking vitamin E along with vitamin C may help prevent pre-eclampsia in women who are at high risk. Pre-eclampsia is characterized by high blood pressure and too much protein in the urine, and is a common cause of premature births. Not all studies agree, however.

Tardive dyskinesia

Some small studies have suggested that vitamin E supplements may help treat tardive dyskinesia (involuntary, repetitive movements that are a side effect of long-term use of some medications). However, not all studies have found that vitamin E can help. The largest study found that taking 1,600 IU of vitamin E daily for at least one year was no better at reducing tardive dyskinesia symptoms than placebo. If you want to try vitamin E for tardive dyskinesia, ask your doctor about it.

Rheumatoid arthritis

One study suggests that taking vitamin E along with standard medications for rheumatoid arthritis may help reduce pain -- but not inflammation -- better than standard medications alone.

The richest source of vitamin E is wheat germ.

Other foods that contain a significant amount of vitamin E include:

• Liver
• Eggs
• Nuts (almonds, hazelnuts, and walnuts)
• Sunflower seeds
• Corn-oil margarine
• Mayonnaise
• Cold-pressed vegetable oils, including olive, corn, safflower, soybean, cottonseed, and canola
• Dark green leafy vegetables like spinach and kale
• Greens (beet, collard, mustard, turnip) sweet potatoes
• Avocado
• Asparagus
• Yams

There are natural and synthetic forms of vitamin E. Health care providers usually recommend natural vitamin E (d-alpha-tocopherol) or natural mixed tocopherols. The synthetic form is called dl-alpha-tocopherol.

Some clinicians prefer mixed tocopherols because it most closely represents whole foods.

Dosages are usually listed in international units (IU).

Most vitamin E supplements are fat-soluble. However, water-soluble E is available for people who have trouble absorbing fat, such as people with pancreatic insufficiency and cystic fibrosis.

Vitamin E is available in softgels, tablets, capsules, and topical oils.

Doses for oral vitamin E generally range from 50 - 1,000 IU. Experts recommend getting vitamin E from food rather than supplements. The Food and Nutrition Board of the Institute of Medicine has set an upper tolerable intake level (UL) for vitamin E at 1,000 mg (1,500 IU) per day for supplemental vitamin E.

Based on clinical trials, the dose often used for disease prevention and treatment for adults is 400 - 800 IU per day. As with all supplements, you should check with a health care provider before giving vitamin E to a child.

Daily intakes of dietary vitamin E are listed below. (Note: 1 mg vitamin E equals 1.5 IU.)

Pediatric

• Newborn to 6 months: 6 IU
• Infants 6 months - 1 year: 9 IU
• Children 1 - 3 years: 9 IU
• Children 4 - 8 years: 10.5 IU
• Children 9 - 13 years: 16.5 IU
• Adolescents 14 - 18 years: 22.5 IU

Adult

• Older than 18 years: 22.5 IU
• Pregnant females: 22.5 IU
• Breast-feeding females: 28.5 IU

Always check with your doctor before taking vitamin E supplements. Vitamin E may increase the risk of bleeding, especially if you are taking anticoagulants (blood thinners) such as warfarin (Coumadin), aspirin, or clopidogrel (Plavix).

If you are being treated with any of the following medications, you should not use vitamin E supplements without first talking to your health care provider:

Antidepressant medications -- Vitamin E interferes with the absorption of the antidepressant desipramine (Norpramin). Desipramine belongs to a class of drugs known as tricyclics. Other tricyclics include imipramine (Tofranil) and nortriptyline (Pamelor).

Antipsychotic medications -- Vitamin E can interfere with the body’s absorption of the antipsychotic medication called chlorpromazine (Thorazine). Chlorpromazine belongs to a class of drugs known as phenothiazines.

Aspirin -- Because vitamin E can increase the risk of bleeding, people who take aspirin should talk to their doctor before taking vitamin E supplements. A study evaluating the effects of vitamin E and aspirin suggests that the combination appears to be safe and may help patients at risk for stroke.

AZT -- Vitamin E may protect against toxicity and side effects from AZT, a medication used to treat HIV and AIDS.

Beta-blockers -- This class of medication is used to treat high blood pressure. Vitamin E interferes with the body’s absorption of propranolol (Inderal), a type of beta-blocker. Other beta-blockers include:

• Acebutolol (Sectral)
• Atenolol (Tenormin)
• Bisoprolol (Zebeta)
• Carteolol (Cartrol)
• Metoprolol (Toprol XL)
• Nadolol (Corgard)
• Propranolol (Inderal)

Bile acid sequestrants -- These medications, used to lower cholesterol, may reduce the body’s absorption of vitamin E. These medications include

• Cholestyramine (Questran, Prevalite)
• Cholestipol (Colestid)

Statins -- Taking a combination of antioxidants, including vitamins E and C, selenium, and beta-carotene, along with niacin and simvastatin (Zocor) seems to counteract the ability of niacin and Zocor to raise “good” HDL cholesterol. It isn’t known whether vitamin E alone would have the same effect, or whether it would happen with other statins. Ask your doctor before taking vitamin E if you also take a statin. Statins include:

• Lovastatin (Mevacor)
• Simvastatin (Zocor)
• Pravastatin (Pravachol)
• Atorvastatin (Lipitor)
• Fluvastatin (Lescol)
• Rosuvastatin (Crestor)

Gemfibrozil -- This medication, used to lower cholesterol, may also reduce vitamin E levels.

Cyclosporine -- Vitamin E may interact with cyclosporine, a medication used to treat cancer, reducing the effectiveness of both vitamin E and cyclosporine. However, another study suggests that the combination of vitamin E and cyclosporine may actually increase the effects of the cyclosporine. Ask your doctor before taking vitamin E if you take cyclosporine.

Chemotherapy drugs -- Some doctors worry that antioxidants like vitamin E may reduce the effectiveness of chemotherapy drugs, including chlorambucil, busulfan, doxorubicine, carmustine, thiopeta, and cyclophosphamide, because these drugs create free radicals. However, other researchers think that antioxidants may make chemotherapy work better because they reduce oxidative stress that might interfere with the death of cancer cells. Talk to your oncologist before taking vitamin E or any supplement.

Tamoxifen -- Tamoxifen, a treatment for breast cancer, boosts blood levels of triglycerides, increasing the risk of developing high cholesterol. In a study of 54 women with breast cancer, vitamins C and E, taken along with tamoxifen, counteracted this effect by reducing “bad” low LDL cholesterol and triglyceride levels while raising “good” HDL cholesterol. Vitamins C and E also made the anti-cancer action of the tamoxifen stronger.

Warfarin (Coumadin) -- Taking vitamin E at the same time as warfarin, a blood-thinning medication, can increase the risk of bleeding.

Orlistat (Alli) -- This medication is used for weight loss. It prevents the absorption of fat and the associated calories. It may also prevent the absorption of fat-soluble vitamins such as vitamin E. Doctors who prescribe orlistat may add a multivitamin with fat-soluble vitamins.

Vitamin E may also interact with:

• Calcium channel blockers, including
  • Nifedipine (Procardia)
  • Amlodipine (Norvasc)
  • Verapamil (Calan, Isoptin)
  • Diltiazem (Cardizem)
  • Felodipine (Plendil)
  • Nisoldipine (Sular)
  • Bepridil (Vascor)
• Fluoxetine (Prozac)
• Fexofenadine (Allegra)
• Omeprazole (Prilosec).

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