Cysteine

The details

Cysteine is a sulfur-containing amino acid that your body naturally makes and uses to build keratin (the protein in your hair, skin, and nails) and gluthatione (a major internal antioxidant). In skincare, it's mostly added as an antioxidant. Some emerging research is also looking at its role in wound healing + evening out pigmentation though most of the pigmentation data comes from oral supplements rather than topical use). Typical use concentrations for this ingredient are usually quite low (under 5% in leave-on skincare). Safety data on cysteine specifically shows it's not a skin or eye irritant.

Found in (2 products)

MediCube

Deep Reviving Peptide Eye Cream

Eye Moisturizers

Reef safeAlcohol-freeParaben-free+2

Wander Beauty

Baggage Claim Eye Masks

Eye Masks

Reef safeAlcohol-freeParaben-free+4