Many Cancer Patients Use Antioxidants

Despite Prevalence, Research Is Limited on Impact of Antioxidants on Breast Cancer Treatment

From the WebMD Archives

June 9, 2009 -- Many breast cancer patients are loading up on antioxidants, a study shows, even though there is limited research on the effect such dietary supplements have on cancer treatments.

Antioxidants are available individually or in multivitamins. There is a widespread belief that antioxidants help with the side effects of cancer treatments, reduce the likelihood of the cancer recurring, and improve overall health. However, there isn't a lot of research about the effects of taking antioxidants during treatments, and some doctors believe supplements could interfere with radiation and certain types of chemotherapy.

Many experts believe that antioxidant supplements can make traditional cancer treatments less effective.

A new study published in the journal Cancer evaluates the prevalence of antioxidant supplement use among female cancer patients and factors that predict antioxidant supplement use. Researchers focused on patients who had already participated in the Long Island Breast Cancer Study Project in the 1990s, which examined environmental exposure and cancer risk.

Between 2002 and 2004, researchers requested a follow-up interview with the participants to discuss antioxidant use. They focused on the antioxidant supplements vitamin C, vitamin E, beta-carotene, and selenium. Out of more than 1,500 original participants, 764 completed the follow-up interview. Out of that group, 663 said they had received traditional treatments such as chemotherapy, radiation, and/or tamoxifen therapy for breast cancer.

Of these 663 women, 60% reported using antioxidants during breast cancer treatment. Most were high-dose users, meaning they took more than what is found in a Centrum multivitamin.

Factors that predicted high antioxidant supplement use were eating more fruit and vegetables at the time of breast cancer diagnosis, history of using herbal products, and taking tamoxifen.

"Given the common use of antioxidant supplements during breast cancer treatment, often at high doses and in conjunction with other complementary therapies, future research should address the effects of antioxidant supplementation on breast cancer outcomes," the researchers write.

WebMD Health News Reviewed by Louise Chang, MD on June 09, 2009



Greenlee, H. Cancer, published online June 8, 2009.

News release, American Cancer Society.

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