Aliases: Se, Selenomethionine, Selenocysteine, Sodium selenate
Pharmacological Mechanism
Incorporated as the 21st amino acid selenocysteine into ~25 mammalian selenoproteins: glutathione peroxidases (GPx, H₂O₂ detox), thioredoxin reductases (Trx redox cycling), iodothyronine deiodinases (T4→T3 conversion). Selenomethionine nonspecifically substitutes for methionine during protein synthesis and acts as a body store.
Dosing Guidelines
PO: Typical 103 mcg (Range: 55–200 mcg)
Target Organ Systems
endocrine
Interactions
Iodine (synergistic): Se and I together required for thyroid function — deiodinases depend on Se, hormone backbone depends on I. Pair, don't substitute.
Liothyronine (synergistic): Deiodinase cofactor for T4 → T3 conversion.