On its Selenium: Fact Sheet for Health Professionals website, the US Office of Dietary Supplements, an agency of the National Institutes of Health, writes that selenium might play a role in the prevention of cancer for the following reasons:
- selenium’s role in DNA repair
- selenium’s role in apoptosis
- selenium’s role in the endocrine and immune systems
- the antioxidant properties of certain selenoproteins
Different Selenium Compounds Have Different Effects on Cancer
The evidence from scientific research into the effect of selenium on cancer prevention can be confusing. Two observations about selenium supplementation may help to explain the confusing results from existing selenium and cancer studies:
1. Different selenium containing compounds differ widely in their ability to prevent cancer. Study results may vary according to the form of the selenium supplement tested.
2. Selenium supplementation may be more effective at cancer prevention in study participants with low baseline selenium status (below 100 mcg/L) and less effective in study participants with high baseline selenium status (above 135 mcg/L).