Last Reviewed: August 22, 2019
Question:
Is it safe to take vitamins or herbal supplements during chemotherapy or radiation therapy?
Answer:
There are several studies showing that vitamin supplements can interfere with the effectiveness of radiation or chemotherapy treatments. The theory is that since antioxidants protect the body's cells from damage, taking excess amounts of supplements may actually protect the cancerous cells from the radiation or chemotherapy. This will decrease how well the treatment works. On the other hand, there have also been studies showing benefit from combining antioxidants and chemotherapy. Because there is not enough research in this area, it is recommended that you avoid extra supplements. Food sources of vitamins, minerals and antioxidants are the best source of these nutrients. It would be difficult to eat enough of a food source to get to the amount you would take in with a supplement (capsule, powder, etc).
Studies found that taking Beta-Carotene supplements (a form of vitamin A) actually resulted in a higher risk of lung cancer in men and more aggressive prostate cancers. Researchers say that getting nutrients in their natural food source is healthier because there are other compounds in the food that likely work together with any one compound to promote health. For these reasons, it is recommended that you avoid extra antioxidant vitamin supplements during treatment. Herbal supplements should also be avoided because they often contain high levels of antioxidants and other compounds that can interact with cancer treatments and other medications. A standard multi-vitamin that contains 100 percent of the recommended daily value (%DV on the label) for vitamins and minerals is safe.
Learn more about supplement use and radiation. Learn more about the safety of dietary supplements.
