Collagen, especially type 1, is the most abundant structural protein in our bodies. It is there in bones, muscles, skin, digestive system, blood vessel, and tendons. Collagen gives our skin elasticity and strength and replaces dead skin cells. Collagen acts like a glue which holds our body together. Natural collagen production slows down as we age. Other factors like eating excess sugar, smoking and daily sun exposure also deplete collagen levels. Collagen is the main component of connective tissue and makes up from 25% to 35% of the protein content of the whole body.