Collagen supplement for skin is made up of amino acids that are the building blocks of protein. It's a fairly complex protein, so it's really difficult for our body to make on its own. Collagen gives strength and elasticity to the skin, promote healing and connective tissue growth, speed wound healing, helps production of new blood cells and connective tissue growth, provide nutrients to other tissues in the body, maintains healthy bones and joints, strengthens hair and nails.