About one third of the protein in your body is used to form collagen, the primary structural protein that forms the matrix of your connective tissues and organs, including your skin. Bone is fifty percent collagen that has been mineralized for a more rigid structure. Skin is seventy-five percent collagen and is a highly flexible structure. If you do not have enough structural integrity in your skin it falls down over time due to gravity and crumples in on itself to form wrinkles. 

Collagen fibers are wrapped into a triple-stranded helix that form high tensile strength cords. Collagen requires vitamin C for synthesis. ...