Vitamin E is a fat-soluble vitamin found in many foods, fats, and oils. It is also an antioxidant that protects body tissue from damage caused by unstable substances called free radicals. Free radicals can harm cells, tissues, and organs.
The build-up of free radicals over time is largely responsible for the aging process and can lead to various health conditions such as heart disease, cancer, and inflammatory conditions (for example, arthritis). 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 and other conditions such as:
- Pancreatitis (inflammation of the pancreas)
- Cystic fibrosis
- Biliary diseases (illnesses of the gallbladder and biliary ducts)
Symptoms of vitamin E deficiency include:
- Muscle weakness
- Loss of muscle mass
- Abnormal eye movements
- Impaired vision
- Unsteady gait
Chronic deficiency may also cause problems with kidney and liver function. In addition, severe vitamin E deficiency can be associated with serial miscarriages and premature delivery in pregnant women.
There is some concern that eating a diet rich in fish oil for many months may induce a deficiency of vitamin E. People who eat a diet high in fish or who take fish oil supplements should ask their doctor if they should take vitamin E supplements.
Uses of Vitamin E
Heart Disease
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. In the last 10 years, clinical studies have reported that the use of vitamin E supplements help prevent heart disease and other types of cardiovascular disease.
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.
However, there is some evidence that vitamin E supplements may reduce atherosclerosis. A 2-year clinical study compared the use of aspirin with and without vitamin E in men with a history of stroke. Researchers found that vitamin E with aspirin significantly reduced the tendency of plaque to stick to vessel walls and decreased the risk of stroke.
Clinical study results have been mixed. More evidence is needed to determine if there are benefits to vitamin E supplementation, whether for prevention or for treatment of cardiovascular disease. However, evidence does support the contribution of vitamin E to the maintenance of vascular function and health -- particularly when used in combination with other antioxidants from fruits, vegetables and nuts.
Cancer
While researchers can draw no firm conclusions about vitamin E's ability to protect against cancer, clinical studies show that people with cancer often have lower levels of vitamin E. Plus, population based trials (observing groups of people over long periods of time) suggest that diets rich in antioxidants, including vitamin E, may be connected to a reduced risk of certain types of cancer, such as colon cancer. Supplementation with vitamin E, though, does not appear to increase the risk of developing cancer in humans.
Laboratory studies have shown that vitamin E inhibits the growth of some cancers in test tubes and animals, particularly hormone responsive cancers such as breast and prostate. Therefore, some researchers believe that supplementation may prove beneficial for both prevention and treatment of these types of cancers.
Despite the encouraging results from test tube and animal studies, research on people has been much less promising. One large clinical study involving nearly 35,000 women, looked at the dietary intake of antioxidants and occurrence of breast cancer after menopause. They found little evidence that vitamin E has a protective effect. More research is needed before researchers can come to any firm conclusions about whether added vitamin E has an impact on cancer and, if so, which forms of the vitamin are most effective for treatment and what the optimal dosage is.
Researchers have also pointed to the fact that the body’s antioxidant defense system is complex, which suggests that focusing on one vitamin in isolation may not be the best approach. In fact, experts believe that dietary forms of antioxidants taken together from foods may be the best way to stave off cancer.
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 no treatment found that the vitamin group became significantly less sensitive to the sun. Another clinical study, lasting for 50 days, also showed a protective effect of the combination of vitamins C and E to UV rays.
Osteoarthritis
A few clinical studies suggest that vitamin E may be helpful in both the treatment (pain relief, increased joint mobility) and prevention (at least in men) of osteoarthritis. In a study comparing vitamin E with diclofenac, a non-steroidal anti-inflammatory drug (NSAID) used to treat osteoarthritis, the two were equally effective. However, other clinical studies have found that vitamin E has a low level of effectiveness for both rheumatoid arthritis and osteoarthritis.
Alzheimer’s Disease
There are several reasons why vitamin E might help treat Alzheimer’s disease. The fat-soluble vitamin readily enters the brain and exerts its antioxidative properties. Since researchers believe oxidative stress contributes to the development of Alzheimer’s disease, in theory antioxidants like vitamin E should help prevent this condition. Clinical studies have suggested that vitamin E supplementation improves cognitive performance in healthy individuals and in those with dementia from causes other than Alzheimer’s (for example, multiple strokes). In addition, vitamin E, together with vitamin C may prevent the development of Alzheimer’s disease.
Menopause
According to a review article on alternatives to hormone replacement therapy (HRT) for women with breast cancer, vitamin E is the most effective option for reducing hot flashes among this group of women. Presumably, this would also be true for women who are not taking HRT. Vitamin E also helps reduce other long-term risks associated with menopause such as Alzheimer’s, macular degeneration and cardiovascular disease.
Eye Health
Because of its antioxidant action, vitamin E may help protect against cataracts (clouding of the lens of the eye) and age related macular degeneration (ARMD, a progressive deterioration in the retina, the back part, of the eye). Both of these eye disorders tend to occur as people age. These conditions seriously compromise eyesight (ARMD is the number one cause of blindness in the United States). To minimize risk of ARMD, experts advocate diets high in vitamins C and E and carotenoids, especially spinach, kale, and collard greens. Taking supplements as a preventive measure, as opposed to getting vitamin E from food sources, remains controversial.
Uveitis is another eye disorder for which the antioxidant vitamins C and E may be helpful. A clinical study of 130 patients with uveitis compared treatment with oral vitamins C and E to placebo and found that those who took the vitamins had significantly better visual clarity than those who took a “dummy pill.” Uveitis is inflammation of the uvea, the middle layer of the eye between the sclera (white outer coat of the eye) and the retina. The uvea contains many of the blood vessels that nourish the eye, so inflammation in this area can affect the cornea, the retina, the sclera, and other important parts of the eye. Uveitis occurs in acute and chronic forms.
Diabetes
People with diabetes tend to have low levels of antioxidants. This may provide an explanation about 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 help control blood sugar levels and lower cholesterol levels in those with type 2 diabetes while protecting against the complications of retinopathy (eye damage) and nephropathy (kidney damage) in those with type 1 diabetes.
Vitamin E may also play a role in the prevention of diabetes. In one clinical study, 944 men who did not have diabetes at were followed for 4 years. Low levels of vitamin E was associated with an increased risk of developing diabetes during that time course.
Pancreatitis
Oxidative stress plays a role in pancreatitis (inflammation of the pancreas). In fact, those with pancreatitis have low levels of vitamin E and other antioxidants. This may be due to lack of absorption of fat-soluble vitamins (such as vitamin E) because the enzymes from the pancreas, which are required to absorb fat, are not functioning properly. Or, this may be due to poor intake because those with pancreatitis are not eating due to pain and need for bowel rest. Some experts advise taking vitamin E and other antioxidants to help reduce the pain and inflammation associated with pancreatitis.
Other
Vitamin E, along with other standard treatments, may also be beneficial for the following:
There is some concern that eating a diet rich in fish oil for many months may induce a deficiency of vitamin E. People who eat a diet high in fish or who take fish oil supplements should ask their doctor if they should take vitamin E supplements.
Uses of Vitamin E
Heart Disease
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. In the last 10 years, clinical studies have reported that the use of vitamin E supplements help prevent heart disease and other types of cardiovascular disease.
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.
However, there is some evidence that vitamin E supplements may reduce atherosclerosis. A 2-year clinical study compared the use of aspirin with and without vitamin E in men with a history of stroke. Researchers found that vitamin E with aspirin significantly reduced the tendency of plaque to stick to vessel walls and decreased the risk of stroke.
Clinical study results have been mixed. More evidence is needed to determine if there are benefits to vitamin E supplementation, whether for prevention or for treatment of cardiovascular disease. However, evidence does support the contribution of vitamin E to the maintenance of vascular function and health -- particularly when used in combination with other antioxidants from fruits, vegetables and nuts.
Cancer
While researchers can draw no firm conclusions about vitamin E's ability to protect against cancer, clinical studies show that people with cancer often have lower levels of vitamin E. Plus, population based trials (observing groups of people over long periods of time) suggest that diets rich in antioxidants, including vitamin E, may be connected to a reduced risk of certain types of cancer, such as colon cancer. Supplementation with vitamin E, though, does not appear to increase the risk of developing cancer in humans.
Laboratory studies have shown that vitamin E inhibits the growth of some cancers in test tubes and animals, particularly hormone responsive cancers such as breast and prostate. Therefore, some researchers believe that supplementation may prove beneficial for both prevention and treatment of these types of cancers.
Despite the encouraging results from test tube and animal studies, research on people has been much less promising. One large clinical study involving nearly 35,000 women, looked at the dietary intake of antioxidants and occurrence of breast cancer after menopause. They found little evidence that vitamin E has a protective effect. More research is needed before researchers can come to any firm conclusions about whether added vitamin E has an impact on cancer and, if so, which forms of the vitamin are most effective for treatment and what the optimal dosage is.
Researchers have also pointed to the fact that the body’s antioxidant defense system is complex, which suggests that focusing on one vitamin in isolation may not be the best approach. In fact, experts believe that dietary forms of antioxidants taken together from foods may be the best way to stave off cancer.
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 no treatment found that the vitamin group became significantly less sensitive to the sun. Another clinical study, lasting for 50 days, also showed a protective effect of the combination of vitamins C and E to UV rays.
Osteoarthritis
A few clinical studies suggest that vitamin E may be helpful in both the treatment (pain relief, increased joint mobility) and prevention (at least in men) of osteoarthritis. In a study comparing vitamin E with diclofenac, a non-steroidal anti-inflammatory drug (NSAID) used to treat osteoarthritis, the two were equally effective. However, other clinical studies have found that vitamin E has a low level of effectiveness for both rheumatoid arthritis and osteoarthritis.
Alzheimer’s Disease
There are several reasons why vitamin E might help treat Alzheimer’s disease. The fat-soluble vitamin readily enters the brain and exerts its antioxidative properties. Since researchers believe oxidative stress contributes to the development of Alzheimer’s disease, in theory antioxidants like vitamin E should help prevent this condition. Clinical studies have suggested that vitamin E supplementation improves cognitive performance in healthy individuals and in those with dementia from causes other than Alzheimer’s (for example, multiple strokes). In addition, vitamin E, together with vitamin C may prevent the development of Alzheimer’s disease.
Menopause
According to a review article on alternatives to hormone replacement therapy (HRT) for women with breast cancer, vitamin E is the most effective option for reducing hot flashes among this group of women. Presumably, this would also be true for women who are not taking HRT. Vitamin E also helps reduce other long-term risks associated with menopause such as Alzheimer’s, macular degeneration and cardiovascular disease.
Eye Health
Because of its antioxidant action, vitamin E may help protect against cataracts (clouding of the lens of the eye) and age related macular degeneration (ARMD, a progressive deterioration in the retina, the back part, of the eye). Both of these eye disorders tend to occur as people age. These conditions seriously compromise eyesight (ARMD is the number one cause of blindness in the United States). To minimize risk of ARMD, experts advocate diets high in vitamins C and E and carotenoids, especially spinach, kale, and collard greens. Taking supplements as a preventive measure, as opposed to getting vitamin E from food sources, remains controversial.
Uveitis is another eye disorder for which the antioxidant vitamins C and E may be helpful. A clinical study of 130 patients with uveitis compared treatment with oral vitamins C and E to placebo and found that those who took the vitamins had significantly better visual clarity than those who took a “dummy pill.” Uveitis is inflammation of the uvea, the middle layer of the eye between the sclera (white outer coat of the eye) and the retina. The uvea contains many of the blood vessels that nourish the eye, so inflammation in this area can affect the cornea, the retina, the sclera, and other important parts of the eye. Uveitis occurs in acute and chronic forms.
Diabetes
People with diabetes tend to have low levels of antioxidants. This may provide an explanation about 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 help control blood sugar levels and lower cholesterol levels in those with type 2 diabetes while protecting against the complications of retinopathy (eye damage) and nephropathy (kidney damage) in those with type 1 diabetes.
Vitamin E may also play a role in the prevention of diabetes. In one clinical study, 944 men who did not have diabetes at were followed for 4 years. Low levels of vitamin E was associated with an increased risk of developing diabetes during that time course.
Pancreatitis
Oxidative stress plays a role in pancreatitis (inflammation of the pancreas). In fact, those with pancreatitis have low levels of vitamin E and other antioxidants. This may be due to lack of absorption of fat-soluble vitamins (such as vitamin E) because the enzymes from the pancreas, which are required to absorb fat, are not functioning properly. Or, this may be due to poor intake because those with pancreatitis are not eating due to pain and need for bowel rest. Some experts advise taking vitamin E and other antioxidants to help reduce the pain and inflammation associated with pancreatitis.
Other
Vitamin E, along with other standard treatments, may also be beneficial for the following:
- Slowing the aging of cells and tissues
- Protecting from frostbite and other cold-induced injuries
- Diminishing the negative effects of environmental pollutants
- Improving anemia
- Speeding wound and burn healing
- Reducing scarring
- Lowering blood pressure
- Slowing progression of Parkinson’s disease
- Easing premenstrual discomfort, especially breast tenderness
- Treating lupus
- Replacing necessary nutrients in those with inflammatory bowel disease, such as ulcerative colitis
- Avoiding miscarriage (also called spontaneous abortion), which may be associated with very low levels of this nutrient
- Helping weight gain and relieving oxidative stress in those with HIV or AIDS
Dietary Sources:
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
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