What to watch with Selen and Sport?

Combining selenium and exercise requires caution. Selenium is an essential trace mineral with antioxidant properties, supporting thyroid function and immune health. During exercise, oxidative stress increases, so adequate selenium may theoretically aid recovery and reduce muscle damage. However, evidence for direct performance enhancement from selenium supplementation in athletes is limited and inconsistent. The main risk is selenium toxicity (selenosis) at intakes above ~300–400 µg/day, which can cause hair loss, nail brittleness, and neurological symptoms. Supplementation without prior testing is not advised. Selenium also interacts with iodine and vitamin E; imbalances can impair thyroid function. For most athletes, a balanced diet (Brazil nuts, fish, eggs) provides sufficient selenium. A home test (e.g., from MyBody-X) can assess status before supplementing. Bottom line: selenium is not a performance booster; focus on overall nutrition and avoid megadoses.