Ingredient review
Quaternium-79 Hydrolyzed Keratin
INCI: Quaternium-79 Hydrolyzed Keratin
A gentle, protein-based conditioner that helps strengthen hair and reduce frizz without weighing it down.
In plain English
This ingredient is a modified version of keratin, the protein that naturally makes up your hair. By attaching a positive charge to the protein, it clings better to the negatively charged surface of damaged hair, filling in gaps and smoothing the cuticle. This makes hair feel softer, look shinier, and tangle less. It also helps reduce static electricity, so your hair is less likely to fly away in dry weather.
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
Quaternium-79 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 Quaternium-79 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
Quaternium-79 Hydrolyzed Keratin is a quaternized (positively charged) derivative of hydrolyzed keratin, a protein obtained from animal sources such as wool or feathers. The quaternization process makes it more substantive to hair and skin, improving its conditioning and antistatic properties.
How it works
When applied in a rinse-off or leave-on product, the positively charged quaternary groups bind to the negatively charged sites on damaged hair or skin. This forms a thin, flexible film that smooths the hair cuticle, reduces friction, and helps prevent moisture loss. The protein also penetrates slightly into the hair shaft to reinforce weak spots, improving tensile strength over time.
Pros
Strengthens hair
The hydrolyzed keratin penetrates the hair shaft to reinforce weak spots, reducing breakage and split ends over time.
Smooths frizz
The positive charge helps the ingredient adhere to hair, smoothing the cuticle and reducing flyaways and static, especially in dry climates.
Cons and cautions
Potential buildup
On fine or low-porosity hair, frequent use can lead to protein buildup, making hair feel stiff or brittle.
Animal-derived
Keratin is typically sourced from animal byproducts, so this ingredient is not suitable for vegans or those seeking plant-based alternatives.
Best for
- People with dry, damaged, or chemically treated hair
- Those seeking a gentle, protein-based conditioner for regular use
Use caution if
- Vegans or those avoiding animal-derived ingredients
- Individuals with very fine or low-porosity hair who may experience protein overload
Usage tips
Safety summary
Quaternium-79 Hydrolyzed Keratin is considered safe for use in cosmetics at typical concentrations. It has a low irritation and comedogenic risk, but individuals with very sensitive skin or allergies to animal proteins should patch test first.
Research notes
Studies on hydrolyzed keratin and its quaternized derivatives show they can improve hair strength, reduce breakage, and enhance moisture retention. However, most evidence comes from in vitro or small-scale human studies, and more large-scale clinical trials are needed to confirm long-term benefits.
Common label clues
- Typical concentration
- 0.5% to 3%
- Regulatory status
- Approved for use in cosmetics in the US, EU, and most other regions. No specific restrictions beyond general cosmetic safety requirements.
- Common uses
- Shampoos, Conditioners, Hair masks, Leave-in treatments
- Environmental note
- Keratin is typically sourced as a byproduct of the wool and poultry industries, which may raise concerns for some consumers regarding animal welfare and sustainability.
Good to know
- Quaternium-79 Hydrolyzed Keratin is often listed near the middle or end of ingredient lists, indicating it is used at moderate to low concentrations.
- It is compatible with most other conditioning agents and surfactants, making it a versatile addition to many hair care formulations.
Common questions
What is Quaternium-79 Hydrolyzed Keratin in beauty products?
This ingredient is a modified version of keratin, the protein that naturally makes up your hair. By attaching a positive charge to the protein, it clings better to the negatively charged surface of damaged hair, filling in gaps and smoothing the cuticle. This makes hair feel softer, look shinier, and tangle less. It also helps reduce static electricity, so your hair is less likely to fly away in dry weather.
What does Quaternium-79 Hydrolyzed Keratin do in a beauty product?
When applied in a rinse-off or leave-on product, the positively charged quaternary groups bind to the negatively charged sites on damaged hair or skin. This forms a thin, flexible film that smooths the hair cuticle, reduces friction, and helps prevent moisture loss. The protein also penetrates slightly into the hair shaft to reinforce weak spots, improving tensile strength over time.
Is Quaternium-79 Hydrolyzed Keratin safe for most people?
Quaternium-79 Hydrolyzed Keratin is considered safe for use in cosmetics at typical concentrations. It has a low irritation and comedogenic risk, but individuals with very sensitive skin or allergies to animal proteins should patch test first.
Who should be careful with Quaternium-79 Hydrolyzed Keratin?
Vegans or those avoiding animal-derived ingredients Individuals with very fine or low-porosity hair who may experience protein overload
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.