Loved
Cysteine
Antioxidant
Antioxidants inhibit oxidation, or a chemical reaction that leads to cell-damage and are found to correct signs of aging, brighten skin tone, and some antioxidants help stimulate collagen.
Explained
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.
See all 711 products with Cysteine
Users who like it
99%
Users who avoid it
1%
What it does
Masking
Obscuring or blocking
Antioxidant
A substance that inhibits oxidation, especially one, such as vitamin e, vitamin c, or beta carotene, that protects cellsfrom the sometimes damaging effects of oxidation.
Prevalence
Less common
Percentage of products that contain it
0.5%
Top categories
Treatments
Cleansers
Haircare
Position
Predominant list placement
Bottom 25%
References
CosIng Data
CosIng ID
75422
INCI Name
CYSTEINE
INN Name
cysteine
EC #
200-158-2 / 222-160-2
All Functions
Antioxidant, Antistatic, Hair Conditioning, Hair Waving Or Straightening, Masking, Redu CI Ng
