Selenium is an essential trace mineral that works as an antioxidant, shielding cells from oxidative stress. It sits at the core of selenoproteins, which help run immune defenses, thyroid hormone metabolism, and reproduction.
People take selenium to support immune health and to keep hair, skin, and nails in good shape. It also assists normal thyroid function, which influences energy regulation and metabolism.
Take selenium once daily with food to improve absorption and reduce stomach upset. Doses vary widely based on the form you choose, whether selenomethionine, selenocysteine, or a chelated form. Excessive amounts can be toxic, so stick within safe limits. Never go above 400 mcg per day for adults unless a doctor directs otherwise. Selenium can interfere with thyroid treatments and chemotherapy drugs. Some supplements contain yeast, so check labels carefully if you have a yeast allergy.