Certain peptides, such as carnosine and glutathione, possess potent antioxidant capabilities. They neutralize excess free radicals in the skin-generated by factors like UV exposure and pollution-thereby mitigating oxidative stress-induced damage to skin cells. Oxidative damage is a key factor contributing to photoaging, pigmentation, and inflammation. Through their antioxidant action, these peptides help delay the onset of aging signs, protect skin cells from environmental stressors, and maintain a healthy, radiant complexion.

Some peptide ingredients, such as Acetyl Hexapeptide-1, can reduce the overproduction of melanin by interfering with tyrosinase activity in melanocytes or by modulating pathways involved in melanin transfer. Excessive melanin deposition is a direct cause of dark spots and uneven skin tone.