Should you take a selenium supplement? Probably not.
Once touted as superheroes, selenium capsules may be more like kryptonite. Selenium, a mineral found naturally in Brazil nuts, red meat, fish, and grains, became popular as a supplement in the late ’90s because researchers believed it could help prevent prostate cancer.
In fact, taking selenium supplements may actually increase your risk of prostate cancer if your current levels are already high enough, a study in the Journal of the National Cancer Institute suggests. “The optimal daily selenium intake is around 55 microgrammes, and the doses you see in these single supplements can be two to six times that,” says study co-author Alan Kristal of the Fred Hutchinson Cancer Research Centre.
You’d need that much only if you have a deficiency, which is pretty unlikely because the typical diet contains plenty of selenium, says Kristal. You probably consume a good deal of selenium in balanced diet containing grains, meats and poultry. In other words, there’s no need to pop a selenium supplement unless your doctor tells you to.
If you pop a multivitamin, select one that has less than 55mg of selenium.