Ingredient review
Sodium Cocoyl Hydrolyzed Keratin
INCI: SODIUM COCOYL HYDROLYZED KERATIN
A mild, protein-based surfactant that cleanses without stripping and helps strengthen hair, but may not suit those with protein-sensitive hair.
In plain English
Sodium Cocoyl Hydrolyzed Keratin is a gentle cleanser made by combining keratin (a protein found in hair and nails) with fatty acids from coconut oil. It helps remove dirt and oil from hair and skin without being harsh, while also depositing a small amount of protein to temporarily strengthen and smooth the hair shaft. Think of it as a mild, nourishing soap that leaves hair feeling softer and less frizzy.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- semi synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Sodium Cocoyl Hydrolyzed Keratin is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging Sodium Cocoyl Hydrolyzed Keratin.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
A semi-synthetic surfactant created by reacting hydrolyzed keratin (broken-down hair protein) with coconut oil fatty acids. It is a mild, anionic surfactant that cleanses while conditioning.
How it works
The molecule has a water-loving head and an oil-loving tail, allowing it to lift dirt and oil from hair and skin. The keratin portion binds to the hair shaft, temporarily filling in gaps and smoothing the cuticle, which reduces frizz and adds shine.
Pros
Mild cleansing
Cleanses effectively without stripping the scalp or hair of natural oils, making it suitable for daily use and sensitive skin.
Strengthens hair
Deposits keratin protein onto the hair shaft, temporarily reinforcing weak spots and reducing breakage for smoother, shinier hair.
Cons and cautions
Protein buildup risk
On low-porosity or protein-sensitive hair, repeated use can lead to stiffness, dryness, or brittleness as protein accumulates.
Animal-derived source
Keratin is typically sourced from animal hair, feathers, or hooves, so it is not suitable for vegans or those avoiding animal products.
Best for
- People with dry, damaged, or frizzy hair
- Those seeking a mild, sulfate-free cleanser
Use caution if
- Individuals with protein-sensitive hair (e.g., low porosity hair that feels stiff or brittle)
- Vegans or those avoiding animal-derived ingredients
Usage tips
Safety summary
Sodium Cocoyl Hydrolyzed Keratin is considered safe for topical use in cosmetics. It has low irritation and comedogenic potential, making it suitable for sensitive skin and scalps. The main concern is protein buildup in certain hair types, not toxicity.
Research notes
Research on this specific ingredient is limited, but studies on similar protein-based surfactants show they are mild and effective cleansers. The keratin component has been shown to temporarily improve hair strength and moisture retention in clinical trials.
Common label clues
- Typical concentration
- 1% to 10% in rinse-off products
- Regulatory status
- Approved for use in cosmetics by the FDA and EU CosIng database. No concentration restrictions for rinse-off products.
- Common uses
- Shampoos, Conditioners, Hair masks, Body washes
- Environmental note
- Derived from renewable coconut oil and keratin byproducts, but the keratin source is animal-based. Biodegradable under standard wastewater treatment conditions.
Good to know
- Sodium Cocoyl Hydrolyzed Keratin is often listed near the top of ingredient lists in sulfate-free shampoos.
- It is considered biodegradable and generally safe for aquatic life at typical rinse-off concentrations.
Common questions
What is Sodium Cocoyl Hydrolyzed Keratin in beauty products?
Sodium Cocoyl Hydrolyzed Keratin is a gentle cleanser made by combining keratin (a protein found in hair and nails) with fatty acids from coconut oil. It helps remove dirt and oil from hair and skin without being harsh, while also depositing a small amount of protein to temporarily strengthen and smooth the hair shaft. Think of it as a mild, nourishing soap that leaves hair feeling softer and less frizzy.
What does Sodium Cocoyl Hydrolyzed Keratin do in a beauty product?
The molecule has a water-loving head and an oil-loving tail, allowing it to lift dirt and oil from hair and skin. The keratin portion binds to the hair shaft, temporarily filling in gaps and smoothing the cuticle, which reduces frizz and adds shine.
Is Sodium Cocoyl Hydrolyzed Keratin safe for most people?
Sodium Cocoyl Hydrolyzed Keratin is considered safe for topical use in cosmetics. It has low irritation and comedogenic potential, making it suitable for sensitive skin and scalps. The main concern is protein buildup in certain hair types, not toxicity.
Who should be careful with Sodium Cocoyl Hydrolyzed Keratin?
Individuals with protein-sensitive hair (e.g., low porosity hair that feels stiff or brittle) Vegans or those avoiding animal-derived ingredients
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.