Lines and creases develop on our faces as the natural collagen in our skin begins to thin and weaken. This process is due to aging, exposure to sun, disease, injury, heredity and lifestyle. Collagen provides skin with texture, resiliency, elasticity and shape. It is the most abundant natural protein found in humans and animals, and provides structural support to skin, 肌肉, 肌腱和骨骼. Fibers of collagen are woven together like threads in fabric to form a framework into which new cells grow.