L-Cysteine
A non-essential amino acid synthesized in the body from l-serine and l-methionine. Cysteine is one of the two “sulfur-containing” amino acids found in proteins, and a precursor to the endogenous antioxidant, glutathione. Cysteine is also an important source of sulfide in human metabolism.
Anecdotally, supplemental cysteine has gained a reputation as a hangover “cure”, as it contributes to the metabolism of acetaldehyde – the toxic ethanol metabolite responsible for those unpleasant, “morning after” symptoms.
