Collagen is an important protein that can be found throughout your body. In fact, it is found in all the connective tissues in your body ranging from your skin and bones, all the way down to your organs and blood vessels. Collagen functions several different ways in your body.
One of the most noticeable functions of collagen is the support it provides for your skin. According to Dr. Eric F. Bernstein of the University of Pennsylvania School of Medicine, collagen makes up approximately 80 percent of the dry weight of your skin. Collagen provides structure to the skin, and works hand in hand with another protein, called elastin, to allow skin the flexibility it needs to stretch and return to its original state as your body moves.
Collagen also has an important function in bone. Bone is made up of a mixture of collagen and a mineral called hydroxyapatite. The two work together to form the structure, flexibility and strength of your bones. According to research done by the Radiocarbon Laboratory, at the University of Waikato in New Zealand, approximately 30 percent of bones are made up of organic materials, of which collagen makes up to 95 percent.
Collagen also provides important functions for your muscles. Collagen fibers provide your muscles with the strength and structure needed to move and function throughout the day. Collagen fibers not only make up your skeletal muscle fibers, but they also make up your smooth muscles (such as those in the bladder and reproductive system) and your cardiac (heart) muscles.
Collagen also provides important function in your blood vessels. Collagen makes up the walls of the veins, arteries and capillaries of the body. This gives the vessels strength, structure and flexibility, all of which are needed to effectively transport blood throughout your entire body.