Lysine Carboxymethyl Cysteinate Best Antioxidant Hydration Anti-Ageing Lysine Carboxymethyl Cysteinate at a glance Amino acid derivative that conditions skin and hair Potent antioxidant that helps “recycle” antioxidants on skin Made from specialized bonds of lysine and cysteine Considered safe and non-irritating as used in cosmetics Lysine Carboxymethyl Cysteinate description Lysine carboxymethyl cysteinate is an amino acid derivative that has skin-conditioning and potent antioxidant properties. This ingredient is supplied as a powder, and its amino acid structure gives it strengthening properties similar to the keratin protein found in skin and hair. The amino acid structure of this ingredient also encourages skin to ramp up its natural levels of the body’s master antioxidant, glutathione. As such, it plays a role in helping skin to visibly repair signs of sun damage, in part by stabilizing other antioxidants within skin’s uppermost layers, such as vitamins C and E. Lysine carboxymethyl cysteinate is not known to irritate skin or eyes when used in amounts up to 5% in cosmetics. Generally, lower amounts (less than 1%) work well in skin care and amounts greater than 2% are used in strengthening-type hair care products. Its lack of irritancy is likely due to its amino acids occurring naturally in skin’s uppermost layers. This ingredient may be animal-derived or synthetic (Paula’s Choice Skincare uses the latter). Related ingredients: Lysine Cysteine Amino Acids