Selenium 200 mcg by Thorne

If you’re looking at selenium for thyroid health, this 200 mcg selenomethionine fits adults with low dietary intake who want a targeted, once-daily selenium supplement. It’s reasonable if your labs show positive Thyroid peroxidase antibodies (TPOAb, the autoantibody in Hashimoto’s) or if TSH, Free T4, and Free T3 suggest sluggish conversion. It’s also a fit if your Selenium, Serum is low or you avoid seafood and Brazil nuts, which are major sources.

Selenomethionine is the most bioavailable form of selenium, absorbed like the amino acid methionine and stably retained in tissues. Selenium is required to build glutathione peroxidases (the enzymes that neutralize peroxide) and iodothyronine deiodinases (the enzymes that convert T4 into active T3). In thyroid autoimmunity, several trials show modest TPOAb reductions within 3–6 months, though symptom changes are less certain. Broad immune claims are overblown; the clearest wins are enzyme-level and thyroid-specific.

Take one capsule daily, with or without food—consistency matters more than timing. 200 mcg is a common proactive dose; for established deficiency, clinicians often replete and then step down after 4–12 weeks, guided by Selenium, Serum and thyroid labs. If you already take a multivitamin or eat Brazil nuts regularly, tally your total selenium to avoid stacking above a safe daily intake. Recheck TSH, Free T4, Free T3, and TPOAb after 8–12 weeks.

Skip extra selenium if your Selenium, Serum is already adequate or you habitually eat high-selenium foods (Brazil nuts, organ meats, lots of seafood). Pregnancy and breastfeeding: stay within your prenatal’s selenium unless your clinician advises otherwise. If you’re on active chemotherapy or radiation, clear any antioxidant regimen with oncology. Chronically high intake can cause hair loss, brittle nails, and a garlic breath odor—signs of excess that warrant stopping and checking labs.