Glycine

Glycine has the distinction of being the chemically simplest amino acid having only a single hydrogen atom as its side chain. It is also a neurotransmitter that has both depressant and stimulant roles in human biochemistry and can be useful as a sleep aid. Although the average diet contains glycine it is not considered an essential amino acid because the human body is capable of synthesizing it from other biological building blocks. Glycine is useful in many medical processes including the treatment of schizophrenia, stroke, sleep problems, benign prostatic hyperplasia (BPH), metabolic syndrome, and some rare inherited metabolic disorders.