Collagen

Collagen is a fibrous protein comprising approximately one third of total protein in mammalian organisms, consisting of a polypeptide with three peptide chains rich in proline and hydroxyproline (CAS# 9007-34-5). In cosmetics, it is typically derived from animal sources such as fish or bovine skin. As a large protein molecule, it functions primarily as a surface-level humectant and skin conditioner when applied topically. It also serves a hair conditioning role per its official CosIng listing.