Selenium Risk Curve

Selenium has a U-shaped risk curve in which both too little and too much can cause problems. Selenium deficiency can impair selenium-dependent antioxidant enzymes and make oxidative stress and inflammation harder to control. Excessive selenium intake may act as a pro-oxidant, interfere with normal cell signaling, and increase oxidative stress. Selenium's benefits are presented as existing within a target range, with risks rising outside that range.