Join Us

Vitamins to Avoid During Radiation

Save as Favorite
Sign in to receive recommendations (Learn more)

Leer esta página en español

Your radiation oncologist may tell you to avoid taking certain supplemental antioxidant vitamins, such as vitamins C, A, D, and E, while you're having radiation therapy. These vitamins might interfere with radiation's ability to destroy cancer cells.

Here's why: Radiation works in part by creating free radicals — highly energized molecules that damage cancer cells. Free radicals in the environment can damage all cells, but in the case of radiation treatment they are focused on the cancer cells. Antioxidants help keep free radicals from forming, or neutralize them if they do form.

Because of the potential conflict between the goal of radiation therapy (to make free radicals) and the goal of antioxidants (to neutralize free radicals), it makes sense to stop taking any antioxidant supplements during radiation therapy. When radiation is finished, you can resume taking your supplements.

Throughout your treatment, do your best to eat a well-balanced diet that contains all of the vitamins you need. Vitamins that come naturally from food are unlikely to interfere with treatment.


Was this article helpful? Yes / No
Rn icon

Can we help guide you?

Create a profile for better recommendations


  • Breast Cancer Stages

    The stage of a breast cancer is determined by the cancer’s characteristics, such as how large it...

  • Breast Self-Exam

    Breast self-exam, or regularly examining your breasts on your own, can be an important way to...

  • Ductal Carcinoma In Situ (DCIS)

    Ductal carcinoma in situ (DCIS) is non-invasive breast cancer. Ductal means that the cancer...


Beta How does this work? Learn more
Are these recommendations helpful? Take a quick survey

Supportpeopleyellow banner mini
Back to Top