Cysteine

Products

Cysteine is commercially available in tablet form as a dietary supplement.

Structure and properties

L-cysteine (C₃H₇NO₂S, M_r = 121.2 g/mol) is a nonessential sulfur-containing amino acid, with a sulfhydryl group on the side chain (-SH).

Effects

Cysteine (ATC V06CA) is a precursor of glutathione, which has antioxidant and cell-protective properties. Keratin, an important building block of hair, nails, and skin, is rich in cysteine. Cysteine is also found in connective tissue. Furthermore, cysteine plays a role in the immune system and in the synthesis of fatty acids. It is also a precursor of taurine.

Indications

• Food supplementation, e.g., for hair loss.
• Malnutrition, lack of or limited ability to provide adequate normal nutrition.