May lower risk
Multivitamins
a daily multivitamin. Vitamins & minerals.
During treatment: In a breast cancer chemotherapy study, multivitamins weren't linked to worse outcomes, unlike single high-dose antioxidants. Tell your care team what you take.
- Verdict
- May lower riskSome studies point to lower risk, but it isn't confirmed.
- How sure
- Rung 2 · LimitedFew, small or conflicting human studies, or only indirect measures such as blood markers.
- How big
- 8% fewer cancers over about 11 years in the Physicians' Health Study II.
The rung shows how sure the science is, not how big the effect is. How to read these ratings
Cancers affected
All cancers combined
What the evidence shows
In the Physicians' Health Study II (14,641 male doctors, about 11 years), a daily multivitamin meant 8% fewer cancers; the 12% drop in cancer deaths wasn't statistically significant. The COSMOS trial (more than 21,000 people, about 3.6 years) found no effect on cancer, though it may have been too short.
What to do
Fine to take a standard multivitamin, but it isn't a reason to skip screening or a healthy diet.
Sources
To take it to your doctor, print this page.
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Related
Every supplement we rated, or follow one cancer step by step: breast cancer, colorectal cancer, lung cancer and prostate cancer.