Supplement Monograph
L-Glutamic Acid
L-Glutamic acid (glutamate) is a nonessential amino acid and the brain's principal excitatory neurotransmitter; also the source of GABA and glutamine.
What Is L-Glutamic Acid?
L-Glutamic acid (glutamate) is a nonessential amino acid that doubles as the most important excitatory neurotransmitter in the brain and as a central hub of amino-acid metabolism. Its sodium salt, monosodium glutamate (MSG), is the source of the savoury “umami” taste.
Role in the Body
Glutamate is the major excitatory neurotransmitter in the central nervous system, acting at NMDA, AMPA and kainate receptors. It is also the precursor to the inhibitory transmitter GABA and to glutamine, and it is the main donor and acceptor of amino groups in transamination reactions that build and break down other amino acids. Dietary glutamate is largely metabolised by the gut and does not freely cross the blood–brain barrier.
As a Supplement
Standalone glutamic acid supplementation is uncommon; the body tightly regulates brain glutamate. It is consumed widely as MSG and is present in most protein foods. Its amide, L-glutamine, is the more common supplement.
Dosage & Safety
Glutamic acid is supplied abundantly by dietary protein and is well tolerated, including as MSG at normal culinary intakes. Supplemental limits, interactions and pregnancy safety are pending the detailed research buildout.
General overview — detailed clinical evidence and citations pending full research buildout.