L-glycine (or glycine) is a nonessential amino acid used by the body to build proteins (non-essential amino acids can either be manufactured directly by the body or can be obtained by conversion from another amino acid). Glycine acts as a neurotransmitter in the central nervous system (CNS).
Glycine and gamma-aminobutyric acid (GABA) are the major inhibitory neurotransmitters in the CNS. Glycine also appears to enhance the activity of the N-methyl D-aspartate (NMDA) receptor complex in the brain, which is involved in memory and learning.
L-glycine supplements are available in capsules and bulk powder.