Collagen and the body1-3,6-9
Collagen is most commonly found in the skin, bones and connective tissue within the body, providing structural support, strength and a degree of elasticity (in combination with elastin). In particular, collagens can be found in the extracellular matrix - an intricate network of macromolecules that determine the physical properties of body tissues.
In the middle layer of the skin - the dermis - collagen helps form a fibrous network, upon which new cells can grow. Collagen is also required in the replacement and restoration of dead skin cells. Some collagens also function as protective coverings for delicate organs in the body such as the kidneys.
As collagen production naturally declines with age, skin loses the elasticity it once had, causing sagging skin, the formation of lines and wrinkles and the weakening of cartilage in joints.
Collagen is secreted by a variety of different cells, but primarily by connective tissue cells. The body consistently produces collagen until around the age of 40. Collagens then begin to decline after this point, with levels having usually declined greatly by the age of 60.