Tryptophan
molecular structure · PubChem
AKA: L-tryptophan, 73-22-3, L-Tryptophane, Tryptophane, (S)-Tryptophan, Trofan, Tryptacin, (2S)-2-amino-3-(1H-indol-3-yl)propanoic acid, Ardeytropin
Synthetic
Skin Conditioner
Hair Care
Amino Acid
Clean
2-Amino-3-indol-3-ylpropanoic acid
Solubility 1 to 5 mg/mL at 68 °F (NTP, 1992)
Formula
C11H12N2O2
Mol. Weight
204.22
CAS #
54-12-6, 73-22-3
Form
Powder
State
L-tryptophan is a white powder with a flat taste. An essential amino acid; occurs in isomeric forms. (NTP, 1992)
Functions
Antistatic
Hair Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Anti-Aging
Antioxidant
Anti-Inflammatory
Reduces flyaways
Softens and detangles hair
Provides scent
Traditional Use
An amino acid discovered in 1901. While not traditionally used in skincare, tryptophan has been studied in modern cosmetics for its role in protein synthesis and potential skin barrier support, though its primary historical use has been in nutrition and mental health applications.
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
The paper trail
🔬Peer-reviewed1 paper →
⚖️Regulatory1 listing →
🛡️Safety-assessed2 reviews →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR