During radiation therapy, you will need to stop taking certain types of vitamins called antioxidants (also termed anti-oxidants), such as vitamin A, vitamin C, vitamin D, and vitamin E. Hereís why:
Normally, antioxidants help combat free radicals, which are unstable molecules that damage cells. In a person not currently undergoing radiation therapy, the action of antioxidants to inhibit free radicals is a good thing for the body.
Radiation therapy, however, works by creating free radicals. So, when you are undergoing radiation therapy, you want the free radicals generated by radiation therapy to be able to damage as many cancer cells as possible.
As soon as you are finished with your radiation treatments, you likely can resume your regular vitamin supplement regimen. If you are undergoing chemotherapy, however, check with your doctors before resuming your vitamin supplementation.