Collagen makes up 25-35% of the body's protein content. This structural protein is responsible for building the connective tissue throughout the body, including your skin, muscle and bones. 87% saw visible results in 6 weeks Collagen makes up 80% of our skin. Our hair, nails and even our joints are made up of lots of collagen, keeping us strong and our skin hydrated. Our collagen is made up of the finest type 1 and type 3 bovine collagen peptides.