Collagen or keratin for hair, is one of them actually the right one?
Collagen is the one everybody takes and keratin is what hair is actually made of, which makes the popularity of collagen a little confusing to me. I have been on collagen about five months for skin and joints and my hair has not changed at all. Before I add a second powder I would like to know whether keratin is the more direct route or whether neither survives digestion. Has anyone compared the two?