It is the key structural material making up scales, hair, nails, feathers, horns, claws, hooves, and the outer layer of skin in tetrapod vertebrates. Keratin also protects epithelial cells from damage or …

Mar 6, 2025 · Keratin is a popular ingredient in hair care products, such as shampoos, conditioners, and treatments, due to its ability to strengthen and repair damaged hair. It can help restore the hair's …

Dec 15, 2025 · Keratin, fibrous structural protein of hair, nails, horn, hoofs, wool, feathers, and of the epithelial cells in the outermost layers of the skin. Keratin serves important structural and protective …

Nov 3, 2025 · Keratin is a naturally occurring protein within the body that aids in the health of the skin, hair, and nails. It is also used in hair products.

What Keratin Actually Is in the Human Body Keratin is a fibrous structural protein naturally produced by the body and is a primary component of the outer layer of skin, hair shafts, and nails. Its ...

Jul 18, 2025 · Keratin is a fibrous structural protein predominantly found in epithelial cells. It is responsible for forming protective layers on the surface of the skin, hair, nails, and other appendages.

keratin (KAYR-uh-tin) A type of protein found on epithelial cells, which line the inside and outside surfaces of the body. Keratins help form the tissues of the hair, nails, and the outer layer of the skin. …