What is type II collagen?

Type II collagen (CII) is a peptide and a major component of joint cartilage. When taken as a supplement, CII is usually in one of two forms: undenatured or hydrolyzed. Undenatured collagen has been minimally processed at a low temperature to keep its peptides mostly intact. Hydrolyzed CII has been processed with a higher degree of heat, acid, and enzymes, resulting in the breakdown of peptides from larger forms into smaller ones.