Thorne’s Skin Health Stack provides comprehensive support for healthy skin, hair, and nails.* Thorne’s Skin Health Stack includes the following two products:  Collagen Plus is a collagen formula designed to nourish hair and nails and support healthy, hydrated skin.* Biotin offers a high concentration of biotin, a B vitamin that promotes fingernail strength and supports healthy skin and hair.* Low biotin levels are associated with hair loss and scaly skin.*