Hydrolyzed Silk
silk uh-MEE-noh AS-ids
INCI: Silk Amino Acids
What Is Hydrolyzed Silk?
Silk Amino Acids are derived from hydrolyzed silk (fibroin or sericin proteins from silkworm cocoons). These small amino acid and peptide fragments have excellent moisture-binding properties and can penetrate the hair shaft to strengthen and add a signature silky feel. Silk has been used in hair care across Asian cultures for centuries.
Source: Silkworm (Bombyx mori) cocoons
Origin: Natural
Also known as: Silk Protein, Hydrolyzed Silk, Silk Peptides, Sericin
What Does Hydrolyzed Silk Do to Your Hair?
Silk Amino Acids penetrate into the hair cortex due to their small molecular size, binding to keratin proteins and improving hair strength and elasticity. They form a transparent film on the hair surface that enhances shine and provides a characteristically smooth, silky texture. They also attract and retain moisture, improving the hair's moisture balance.
Best For
All hair types, damaged hair, dull hair, color-treated hair, fine hair, dry hair
Not Recommended For
Not significantly problematic for any hair type; not vegan
Concentration Matters
0.1-5%
Hair Type Compatibility
Method Compatibility
Safety & Regulation
Very safe for topical use. Non-irritating and non-sensitizing. Sericin (silk gum) protein may occasionally cause irritation in very sensitive individuals, though this is rare. Not suitable for those seeking vegan or cruelty-free products.
FDA Status: Generally Recognized As Safe
FDA permits use in cosmetics without restrictions. Widely used in Asian beauty products with long safety history.
EWG Score: 1/10
HairAide Verdict
Silk Amino Acids are one of the best ingredients for adding genuine shine and silky smoothness to hair. They provide lightweight protein strengthening without the risk of protein overload. HairAide recommends them especially for dull, lackluster hair that needs a visible boost in shine and softness.
Products That Contain Hydrolyzed Silk
Conditioners, hair masks, shine serums, styling products, leave-in treatments
Alternatives to Hydrolyzed Silk
If you want to avoid Hydrolyzed Silk, look for products with these ingredients instead:
Hydrolyzed Wheat Protein, Hydrolyzed Rice Protein, Keratin, Oat Amino Acids
Frequently Asked Questions
Yes, Hydrolyzed Silk has a safety rating of 8/10 and is generally considered safe for use in hair products. Very safe for topical use. Non-irritating and non-sensitizing. Sericin (silk gum) protein may occasionally cause irritation in very sensitive individuals, though this is rare. Not suitable for those seeking vegan or cruelty-free products.
Hydrolyzed Silk is CG-method approved and is generally considered safe for curly hair.
Yes, Hydrolyzed Silk is approved for the Curly Girl method.
Some alternatives to Hydrolyzed Silk include: Hydrolyzed Wheat Protein, Hydrolyzed Rice Protein, Keratin, Oat Amino Acids
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