Selenium: A Small Mineral With a Big Role

Selenium is an essential trace mineral that plays an important role in immune function, thyroid health, and antioxidant protection. Your body uses selenium to make selenoproteins, which help protect cells from oxidative damage and support normal thyroid hormone metabolism.

Why is selenium important?

• Supports immune function and helps the body respond appropriately to infections

• Supports thyroid health and thyroid hormone metabolism

• Provides antioxidant protection by supporting enzymes that protect cells from oxidative stress

• Supports overall cellular health and normal metabolism

Can you get too much?

Yes. Selenium has a relatively narrow range between adequate intake and excess. Too much selenium over time can cause hair loss or brittle nails, a metallic or garlic-like breath odor, nausea, diarrhea, fatigue, and nervous-system symptoms such as tremors or neuropathy.

What about too little?

Selenium deficiency can impair normal thyroid and immune function. Some research suggests selenium status may influence how the body responds to certain viral infections, but selenium should not be presented as a treatment or guaranteed defense against viruses.

The takeaway: More isn't necessarily better. If you're considering supplementation, check your nutritional status when appropriate and discuss the right dose with your healthcare provider, especially if you already take a multivitamin or other supplements containing selenium.