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Supplements for Cancer: Antioxidants

Antioxidants are substances found in abundance in fruits and vegetables – and in lesser amounts in nuts, grains, and meat. These phytochemicals fight certain oxygen molecules in your body known as free radicals, which can damage DNA and contribute to the development and proliferation of cancerous cells.

Common antioxidants include vitamins A, C, and E, selenium, certain compounds in green tea and melatonin, a hormone made by the pineal gland in the brain.

The use of antioxidants for cancer prevention and treatment is a controversial and confusing topic. Although experts once believed that megadoses of certain antioxidants, including vitamins A and E, might be beneficial, clinical studies have raised questions about the safety of this practice. Studies have shown that high doses of certain antioxidants can increase cancer occurrence in some populations. For instance, smokers who take high doses of beta carotene are at increased risk for lung cancer.

Some experts worry that the use of antioxidants during radiation therapy and chemotherapy might serve to protect the very cancer cells that are being targeted. A 2008 study in Cancer Research showed that vitamin C supplements blunted the effectiveness of chemotherapy by 30% to 70%.

Although more research needs to be done, there is data to suggest that antioxidant supplements may improve quality of life for some cancer patients. For example, the combined use of antioxidants in green tea, melatonin, and multivitamins containing high doses of vitamins C and E was shown to reduce pain and fatigue in patients being treated for pancreatic cancer.

In the meantime, there’s no doubt that a diet high in antioxidant-rich foods, such as fruits and vegetables, has numerous health benefits.

Be sure to talk with your cancer treatment team before taking antioxidant supplements when you have cancer.

2. Coping with Treatment Side Effects When You Have Cancer

People with cancer often turn to vitamins and supplements to reduce the side effects of cancer treatment: Nausea from chemotherapy, nerve pain, or debilitating fatigue.

Keep in mind, there are hundreds of chemotherapy drugs. The vitamins and supplements that may help you will depend on your specific treatment.

To optimize your health and reduce the risk of dangerous interactions, don’t take supplements for side effects without talking with your cancer treatment team. Your cancer doctors can help you develop a comprehensive treatment.

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