Is L-Lysine safe in cosmetics?
L-Lysine has a safety rating of "EXCELLENT" in our database. EU status: permitted. US status: permitted.
EXCELLENT
Active Ingredient
L-Lysine
Also known as: Biolys, Hexanoic acid, 2,6-diamino-, (S)-, 4-04-00-02717, BRN 1722531, 2,6-Diaminohexanoic acid, (S)- (+15 more)
INCI: LYSINE
L-Lysine (CAS 56-87-1) is a cosmetic active ingredient functioning as Essential amino acid with a positively charged side chain (pKa ~10.5) at. EU Regulation 1223/2009 status: permitted. Industrial safety data is also available in the chemical safety database. Same-CAS public records also appear in industrial chemical safety and pharmaceutical data.
Function
Essential amino acid with a positively charged side chain (pKa ~10.5) at physiological pH. In cosmetic context: facilitates peptide-membrane adhesion by binding to the negatively charged lipid bilayer; enhances peptide penetration when positioned at sequence extremities; structural component of collagen-stimulating sequences (KTTKS in Palmitoyl Pentapeptide-4/Matrixyl). Serves as counter-ion for pH adjustment and as a skin conditioning humectant.
Editorial assessment
EXCELLENT
Preliminary editorial note — not a computed safety verdict.
Chemistry & Identifiers
IUPAC Name
(2S)-2,6-diaminohexanoic acid
InChIKey
KDXKERNSBIXSRK-YFKPBYRVSA-N
Regulatory Status
EU EU Status
permitted
US US Status
permitted
US Notes
FDA GRAS as direct food additive. CIR Expert Panel assessed safe for cosmetic use. No concentration restrictions.
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for L-Lysine.
Calculate MoS for your specific formulation with the MoS Calculator.
PubChem Annotations
Safety and regulatory annotations from PubChem (NCBI) aggregated sources.
Safety (1)
Carcinogen Classification
No indication of carcinogenicity to humans (not listed by IARC).
Source: Toxin and Toxin Target Database (T3DB)
Regulatory (2)
JECFA Number
1439
Source: WHO/JECFA
JECFA Evaluation
L-LYSINE | 2008 | No safety concern at current levels of intake when used as a flavouring agent | Not evaluated using the Procedure for the Safety Evaluation of Flavouring Agents; the substance is a macronutrient and a normal component of protein and, as such, human exposure through food is orders of magnitude higher than the anticipated level of exposure from use as a flavouring agent | ">RS…
Source: WHO/JECFA
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Anti-static agent
Flavouring and nutrient
Pharmaceutical
Softener and conditioner
Solvent
Regulatory List Membership (1)
FDA Substances Added to Food (EAFUS)
Editorial summary
Preliminary editorial summary for L-Lysine — not a computed safety verdict. See the sourced toxicological data above.
Regulatory Flags
gras-fda
cir-approved
essential-amino-acid
penetration-enhancer
positive-charge
fda_food_additive
jecfa_safe
Known Synonyms
Biolys
Hexanoic acid, 2,6-diamino-, (S)-
4-04-00-02717
BRN 1722531
2,6-Diaminohexanoic acid, (S)-
EINECS 200-294-2
Lysinum
UNII-K3Z4F929H6
(2S)-2,6-diaminohexanoic acid
(S)-2,6-Diaminohexanoate
(S)-2,6-diamino-Hexanoate
(S)-2,6-diamino-Hexanoic acid
(S)-a,e-Diaminocaproate
(S)-a,e-Diaminocaproic acid
(S)-alpha,epsilon-diaminocaproic acid
2,6-Diaminohexanoate
6-Amino-Aminutrin
6-Amino-L-Norleucine
L-2,6-Diainohexanoate
L-2,6-Diainohexanoic acid
Chemical Function
Anti-static agent
Softener and conditioner
Solvent
Flavouring and nutrient
Pharmaceutical
Regulatory Lists
Cleaning products and household care - laundry and fabric treatment - laundry stain remover; detected; Europe
Cleaning products and household care - laundry and fabric treatment - laundry stain remover; Europe
Cleaning products and household care - laundry and fabric treatment - laundry stain remover; Europe
Europe
food_additive; Substances Added to Food (formerly EAFUS) (2/2019)
Canada; pharmaceutical
Canada; pharmaceutical
Cross-Vertical Safety Context
Same-CAS public records found in pharmaceutical data.
SOURCE
ChEMBL / DrugCentral / FAERS
DB_PHARMA CAS match
Pharmaceutical Data
Same-CAS rows from the pharmaceutical spoke database.
Compound
LYSINE
ChEMBL ID
CHEMBL8085
Max Phase
2
Adverse Event Associations
72
Frequently Asked Questions
Is L-Lysine allowed in the EU?
L-Lysine EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
What does L-Lysine do in cosmetics?
L-Lysine functions as: Essential amino acid with a positively charged side chain (pKa ~10.5) at physiological pH. In cosmetic context: facilitates peptide-membrane adhesion by binding to the negatively charged lipid bilayer; enhances peptide penetration when positioned at sequence extremities; structural component of collagen-stimulating sequences (KTTKS in Palmitoyl Pentapeptide-4/Matrixyl). Serves as counter-ion for pH adjustment and as a skin conditioning humectant.. It is classified as a Active Ingredient in our database. CAS number: 56-87-1.
Is L-Lysine used outside cosmetics?
L-Lysine also appears in industrial chemical safety and pharmaceutical data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.
Compliance Tools
Check L-Lysine compliance across multiple jurisdictions:
Ingredient Decoder
Paste a full ingredient list for instant analysis
82 Allergen Checker
Check for EU declarable fragrance allergens
Substance Compliance
Check compliance across multiple jurisdictions
MoS Calculator
Calculate Margin of Safety using SCCS methodology
Heavy Metal Limits
Compare limits across jurisdictions
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