Myths vs facts: Selen and longevity

Selenium is an essential trace mineral that acts as an antioxidant via selenoproteins and supports thyroid function. Some observational studies suggest a link between adequate selenium status and lower mortality, especially in older adults. However, evidence for direct lifespan extension through selenium supplementation in humans is weak. Randomized controlled trials show no consistent benefit, and high doses can be toxic (selenosis). Most people in Western countries are adequately supplied; supplementation without proven deficiency is not recommended. The myth that selenium alone prolongs life is not scientifically supported. Instead, a balanced diet with natural selenium sources like Brazil nuts, fish, and eggs should be prioritized. The overall evidence is mixed: there are mechanistic hints but no strong human studies demonstrating clear longevity extension.