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E621Caution

Monosodium glutamate (MSG)

Group: Flavour enhancers · in the book

Harm level3 of 5In moderation

In plain words

Monosodium glutamate (MSG) is the best-known flavour enhancer, giving food a savoury umami taste. You find it in instant soups, stock cubes, crisps, processed meats and Asian dishes, sometimes hidden behind names like yeast extract.

Where you find it: instant soups, crisps, stock cubes, seasoning mixes

Our recommendation

We recommend limiting it; if you react to it, read labels carefully.

Possible risks and effects

  • Sensitive people report headache, nausea or palpitations after larger doses; controlled studies support this only weakly.
  • The strong savoury taste may encourage overeating ultra-processed foods.

For experts

The sodium salt of glutamic acid, produced by fermentation; in food it behaves like natural glutamate. The so-called Chinese restaurant syndrome has not been reliably confirmed in controlled studies. In 2017 EFSA set a group ADI for glutamates E620–E625 and noted that some population groups with high intake may exceed it.

Check another E-number

More from this group

E620Glutamic acidE622Monopotassium glutamateE627Disodium guanylateE631Disodium inosinateE635Disodium 5'-ribonucleotidesE640Glycine

This information is educational and based on EFSA assessments and available studies; it does not replace medical advice. With allergies, intolerances or illness, follow your doctor’s advice.