Selenium 200 mcg by Pure Encapsulations

A selenium supplement makes sense if your diet is light on seafood and Brazil nuts, your Plasma Selenium is low, or your thyroid labs are off. People with autoimmune thyroiditis and positive Thyroid Peroxidase Antibodies (TPO antibodies, the immune signal against the thyroid) often use selenium alongside levothyroxine. Vegans on restrictive diets, those after bariatric surgery, and dialysis patients should discuss selenium status with a clinician and track TSH, Free T4, and TPO antibodies over time.

This uses selenomethionine, the form your body absorbs well and can store by substituting for methionine in proteins. It feeds selenoproteins such as glutathione peroxidases (enzymes that clear peroxides), thioredoxin reductase (keeps cells’ redox balance), and deiodinases (convert T4 to the active thyroid hormone T3). In practice, that supports antioxidant defenses and thyroid hormone activation, and in some patients modestly lowers TPO antibodies and hs-CRP, an inflammation marker, over several months.

Take one capsule daily with a meal. If you take levothyroxine, keep that on an empty stomach in the morning and take selenium later with food to keep routines clean. Expect thyroid antibody and symptom changes, if they occur, within 8 to 24 weeks. This is a repletion-level daily dose; if your Plasma Selenium is already adequate, consider less from a multivitamin or food rather than layering extras.

Avoid stacking this with a high-selenium multivitamin and frequent Brazil nut intake, which can push you into excess. Too much selenium causes brittle nails, hair loss, and a garlic-like breath odor. Pregnancy and breastfeeding typically call for lower amounts than 200 mcg, so stick to your prenatal unless your clinician advises otherwise. If you have chronic kidney disease or are on dialysis, use only with lab monitoring.