Monosodium glutamate

Monosodium glutamate is notable for histamine. Clear on tyramine, salicylate, sucrose, FODMAPs, lactose, oligosaccharides, sorbitol, fructose, nickel, oxalates and gluten.

Monosodium glutamate contains moderate levels of histamine. MSG (E621) is the weakest entry on this whole axis, and it is worth being blunt: the 'Chinese restaurant syndrome' link has largely failed double-blind placebo-controlled testing, and glutamate is not a histamine liberator by any established mechanism. It stays flagged because histamine lists conventionally include it and because MSG travels with genuinely high-histamine company - soy sauce, aged cheese, yeast extract - which is the likelier explanation for a reaction. The Swiss list rates it 2 of 3 and marks it L, its letter for liberators of mast cell mediators — a presumed reason rather than a measurement. EFSA set the first ADI for these additives at 30 mg per kilo of body weight a day, then found exposure above it — and above DOSES ASSOCIATED WITH ADVERSE EFFECTS IN HUMANS — for some population groups. That answers a different question from the blinded challenge: habitual intake, not a meal. Amounts vary by brand and recipe, so always check the label of the exact product.