COLLAGEN Fun fact: it derives from the Greek word “kola,” which means “glue.” Makes sense since it is the protein structure that holds much of our body together. It’s found in roughly one-third of our bodily protein composition, including bones, muscles, tissue, tendons, ligaments, blood vessels and even teeth! The amino acids in collagen help strengthen and protect skin, hair and nails while also fending off nasty free radicals.