Keratin Peptides
Broken-down keratin protein fragments that coat and reinforce damaged hair shafts.
Back to all peptides
See this on a product label?
Keratin-derived peptides
Hair and lash products use INCI names too—often longer chemical names beside marketing names like Capixyl.
Structure (cute edition)
This peptide is a short chain of about 4 amino acids—think of it as a tiny protein necklace on your label.
INCI: Keratin-derived peptides · ~4 amino acids in our simplified view
Research & public records
Counts and links from public databases (PubMed, ClinicalTrials.gov, Wikidata, NIH drug nomenclature). Educational only — not medical advice.
PubMed: 42 indexed papers (search PubMed)
- Hydrolyzed Keratin Peptide Enhances Hair Condition and Promotes Hair Regeneration. · Journal of medicinal food
- Bionic polydopamine in-situ functionalized keratin double network gel with adsorption and self-adaptability: promoting uranium entrapment from seawater. · International journal of biological macromolecules
- Keratinous bioresources: their generation, microbial degradation, and value enhancement for biotechnological applications. · World journal of microbiology & biotechnology
- Enhanced Delivery of Biomolecules into Caco2 Cells Based on the Cell-Penetrating Ability of Keratin Peptides. · ACS applied materials & interfaces
- Electrospun Poly-ε-Caprolactone Nanofibers Incorporating Keratin Hydrolysates as Innovative Antioxidant Scaffolds. · Pharmaceuticals (Basel, Switzerland)
- New Inhibitor Based on Hydrolyzed Keratin Peptides for Stainless Steel Corrosion in Physiological Serum: An Electrochemical and Thermodynamic Study. · Polymers
- Porcupine quills keratin peptides induces G0/G1 cell cycle arrest and apoptosis via p53/p21 pathway and caspase cascade reaction in MCF-7 breast cancer cells. · Journal of the science of food and agriculture
- Affinity of Keratin Peptides for Cellulose and Lignin: A Fundamental Study toward Advanced Bio-Based Materials. · Langmuir : the ACS journal of surfaces and colloids
Clinical trials: 19 studies on ClinicalTrials.gov (view search)
- Evaluate the Efficacy and Safety of Hydrolyzed Keratin Peptide Powder on Hair Health · COMPLETED
- Study to Investigate the Effects of Different Doses of S-adenosyl-L-methionine (SAMe) in Subjects With Nonalcoholic Fatty Liver Disease and Non-treated Matched Healthy Volunteers as Control Group · COMPLETED
- EMI-137 in Laparoscopic Colonic Resections · COMPLETED
- Study Evaluating the Effect of Nutra Harmony "Biotin, Collagen and Keratin Beauty Complex" Dietary Supplement on Hair Thickness and Hair Strength in Adults With Self-Perceived Thinning Hair · ACTIVE_NOT_RECRUITING
- Biochemical Correction of Severe EB by Allo HSCT and "Off-the-shelf" MSCs · COMPLETED
- A Trial To Assess Safety And Tolerability Of PF-04691502 In Cancer Patients · COMPLETED
- Role of Lisinopril in Preventing the Progression of Non-Alcoholic Fatty Liver Disease, RELIEF-NAFLD Study · ACTIVE_NOT_RECRUITING
- Efficacy and Tolerability of the Use of Varicell Compared With Daflon · UNKNOWN
ChEMBL: CHEMBL1160639
What brands say it does
Hydrolyzed keratin peptides are small enough to penetrate the cuticle and fill gaps in damaged hair. They improve feel and reduce breakage rather than growing new follicles. Common in bond-repair and smoothing lines.
Where you’ll find it
Bond builders, leave-in conditioners, heat protectants, and salon keratin treatments.
Other names you might see
Hydrolyzed keratin
Keratin amino acids
Keratin-derived peptides
Similar peptides
Educational only—not medical advice. Hair loss has many causes; see a dermatologist or trichologist for persistent thinning.