Serine
molecular structure · PubChem
AKA: L-serine, 56-45-1, (S)-2-Amino-3-hydroxypropanoic acid, (S)-Serine, Beta-Hydroxyalanine, L-(-)-Serine, L-ser, (2S)-2-amino-3-hydroxypropanoic acid, Serina
Synthetic
Skin Conditioner
Hair Care
Amino Acid
Clean
2-Amino-3-hydroxypropanoic acid
Effective at 1.0%
Solubility 425000
Formula
C3H7NO3
Mol. Weight
105.09
CAS #
302-84-1, 56-45-1
Form
Powder
State
Solid; [Merck Index] White powder; [Sigma-Aldrich MSDS]
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.
Skin Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Locks in moisture
Traditional Use
An amino acid discovered in the late 19th century. Identified as a component of skin proteins and incorporated into skincare products in the latter 20th century based on its natural role in skin hydration and barrier function.
EWG
1
CIR
Safe as used
Pregnancy
Yes
CIR Safety Findings
Not Phototoxic
medical-approval
all-shades-safe
Concentration Guide
1e-05%
2.0%
0%100%
Reported use
CIR reported use: 0.0003-0.008 | 0.00001-2 | 0.00003-2
Regulatory Agencies
Skin Types
●all-skin-types
Best For
Dehydration
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