The same as collagen, elastin is present in many structure in the body, not just in the skin. Elastin makes up only around 3% of the skin, whereas collagen makes up 70% of the dry mass of skin. Degradation of elastic fibers is associated with UV exposure, and the elastosis is one of the key features of photoaged skin. The fact that new elastin fibers are not produced is a challenge in the aesthetic industry.
Collagen, is an abundant protein, it is the main component of connective tissue and is found not only in fibrous tissue like the skin, but also tendons, ligaments, cartilage, bones, corneas and blood vessels. There are 18 collagen subtypes, 11 of which are in the dermis of the skin.