Generations later, it turns out they were onto something big. In fact, cocooning your face in bird poo can actually be seriously beneficial to the skin. According to Joshua Zeichner M.D.,
Director of Cosmetic and Clinical Research in Dermatology at Mount Sinai Hospital in New York City: "The birds are fed a specialized diet to produce droppings rich in urea and the amino acid guanine. Guanine is a nitrogenous base which is a backbone to forming DNA and thought to give fish scales their shine; urea is a humectant commonly used in moisturizers."