Translation-initiator amino acid (every eukaryotic protein starts with Met). Converts to same (S-adenosyl-methionine) — the principal methyl donor for >100 methyltransferases including DNMT (DNA), HMT (histones), COMT (catecholamines), GNMT (creatine), and PEMT (phosphatidylcholine). Demethylated to S-adenosyl-homocysteine (SAH) → homocysteine → back to methionine (methionine sam cycle B12-dependent methionine synthase) or to cysteine (transsulfuration).
Dosing Guidelines
PO: Typical 1.33 g (Range: 1–2 g)
Target Organ Systems
digestive
nervous
Interactions
SAMe (synergistic): Methionine is the direct precursor of SAMe. SAMe is the preferred supplement form.
TMG (Betaine) (synergistic): TMG donates a methyl back to homocysteine → methionine via BHMT (B12-independent remethylation).