We hear so much about the benefits of antioxidants but could they pose a risk to cancer patients? Antioxidants are molecules that can help prevent or delay some forms of cell damage. Antioxidants are touted as important in treating and protecting everything from aging skin, to seasonal colds, to heart health and even cancer prevention. Antioxidant-rich foods are part of a healthy, well-rounded diet and consumption of antioxidants, whether in food or supplement form is generally encouraged by physicians. So, if antioxidants are so good at protecting cells how could they possibly be harming those who have been diagnosed with cancer. New studies are showing that antioxidants may pose more harm than good for cancer patients.
When you have cancer and are undergoing treatment the primary goal is to stop the growth of the cancer but antioxidants may actually accelerate the growth of cancer. Scientific American explains how antioxidants may accelerate cancer growth and the studies that provide further evidence, “The work, conducted in mice, shows that antioxidants can change cells in ways that fuel the spread of malignant melanoma—the most serious skin cancer—to different parts of the body. The progression makes the disease even more deadly. Earlier studies of antioxidant supplement use by people have also hinted at a cancer-promoting effect. A large trial reported in 1994 that daily megadoses of the antioxidant beta-carotene increased the risk of lung cancer in male smokers by 18 percent and a 1996 trial was stopped early after researchers discovered that high-dose beta-carotene and retinol, another form of vitamin A, increased lung cancer risk by 28 percent in smokers and workers exposed to asbestos. More recently, a 2011 trial involving more than 35,500 men over 50 found that large doses of vitamin E increased the risk of prostate cancer by 17 percent. These findings had puzzled researchers because the conventional wisdom is that antioxidants should lower cancer risk by neutralizing cell-damaging, cancer-causing free radicals. But scientists now think that antioxidants, at high enough levels, also protect cancer cells from these same free radicals. “There now exists a sizable quantity of data suggesting that antioxidants can help cancer cells much like they help normal cells,” says Zachary Schafer, a biologist at the University of Notre Dame, who was not involved in the new study. Last year the scientists behind the melanoma study found that antioxidants fuel the growth of another type of malignancy, lung cancer.” While healthy people may benefit from the protection from oxidation and free radicals, those who have cancer and are undergoing treatment should avoid excess antioxidants to ensure that they are not fueling the growth of cancer in their body.