Collagen occurs in many places throughout the body and over 90% of the collagen in the body, however, is type I.

The five most common types are:
 - Collagen I: skin, tendon, vascular ligature, organs, bone
 - Collagen II: cartilage 
 - Collagen III: is found in more distensible tissues like blood vessels, forming small fibrous elements
 - Collagen IV: forms basal lamina, the epithelium-secreted layer of the basement membrane.
 - Collagen V: cell surfaces, hair and placenta

A combination of collagens help support healthy skin, joint and tendons.