Vitamin E, an antioxidant, has been cited in medical studies as a possible cancer preventative. The basis for theories concerning vitamin E and cancer rests on the ability of antioxidants to fight oxidative DNA damage, which is attributed to causing a number of types of cancer. Substantiation of vitamin E’s cancer fighting abilities has been elusive, however, since medical studies have delivered conflicting outcomes.
Much of the hope about vitamin E and cancer has come from animal and lab studies. Some studies on vitamin E and cancer seem to indicate that low levels of vitamin E in the body can lead to a greater risk for cancer. Researchers have also noted that cancer patients often have low levels of vitamin E, although this could be an effect of the cancer or cancer treatments.
The Women’s Health Study, published in 2005, examined the effects of vitamin E and cancer, among other things. This study was initiated in 1991 and found no evidence of reduced cancer risk among women who took higher doses of vitamin E. Rates for lung, breast and colorectal cancer were not impacted by taking vitamin E. Studies have also been conducted to see if vitamin E could prevent cancer recurrence, and the results of these studies were also negative.
A study of 29,000 male smokers who took 50 milligrams of Vitamin E daily had conflicting results. The research found no effect on rates of lung cancer. According to study results, rates for prostate and colorectal cancer were lower, while the incidence of bladder and stomach cancer was higher.
Most vitamin E supplements are made from alpha-tocopherol acetate. This form of vitamin E has not been shown to have any effect on breast cancer rates. Another form of vitamin E, tocotrienol, was shown to block some breast cancer cells, but this study was conducted with the use of cultures and not tested on humans.
Many experts feel that a balanced diet can provide adequate amounts of vitamin E. Others suggest finding supplements that contain the tocotrienol form of vitamin E because it has been shown to inhibit the growth of some breast cancer cells in a lab environment. These vitamin E capsules are available from a variety of sources.
Vitamin E occurs naturally in plants. Natural sources of vitamin E include almonds, avocado and broccoli. Vitamin E is also added to other foods. Although vitamin E cannot be stored for more than six weeks in the human body, deficiency is rare and usually found only in people with genetic conditions.