Lysine
molecular structure · PubChem
AKA: L-lysine, 56-87-1, Lysine acid, H-Lys-oh, (S)-Lysine, Aminutrin, Alpha-Lysine, (S)-2, 6-Diaminohexanoic acid, L-lys
Synthetic
Skin Conditioner
Amino Acid
Synthetic
Clean
L-Lysine (abbreviated as Lys or K) is an alpha-amino acid with the chemical formula HO2CCH(NH2)(CH2)4NH2. This amino acid is an essential amino acid, which means that humans cannot synthesize it. Its codons are AAA and AAG.
L-Lysine is a base, as are arginine and histidine. The epsilon-amino group often participates in hydrogen bonding and as a general base in catalysis. Common posttranslational modifications include methylation of the epsilon-amino group, giving methyl-, dimethyl-, and trimethyllysine. The latter occurs in calmodulin. Other posttranslational modifications include acetylation. Collagen contains hydroxylysine which is derived from lysine by lysyl hydroxylase. O-Glycosylation of lysine residues in the endoplasmic reticulum or Golgi apparatus is used to mark certain proteins for secretion from the cell.L-lysine is an essential amino acid. Normal requirements for lysine have been found to be about 8 g per day or 12 mg/kg in adults. Children and infants need more- 44 mg/kg
Effective at 0.35%
Solubility 1000000
Formula
C6H14N2O2
Mol. Weight
146.19
CAS #
56-87-1
Form
Liquid
State
Liquid
Functions
Skin Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Reduces Static
Conditions Hair
Conditions Skin
Softens & Smooths
Reduces Flyaways
Detangles Hair
Traditional Use
An amino acid discovered in the late 19th century. While primarily known for internal immune support, L-lysine has been studied since the 1980s for skincare applications, particularly for supporting skin barrier function and reducing inflammation.
EWG
1
CIR
Safe
Pregnancy
Yes
CIR Safety Findings
Not Phototoxic
all-shades-safe
Concentration Guide
2e-05%
0.7%
0%100%
Reported use
CIR reported use: 0.0009-0.001 | 0.00002-0.7 | 0.00003-0.6
Regulatory Agencies
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
The paper trail
🔬Peer-reviewed1 paper →
⚖️Regulatory0 listings
🛡️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