and there are two main forms of hair pigment. There's eumelanin and pheomelanin. Eumelanin is what we see in brunettes and darker-haired people, and pheomelanin is what we see in blonds and redheads.

Eumelanin is a black-brown pigment, and pheomelanin is a red-yellow pigment ... cause early greying because they just coat the hair strand without changing its structure. However, permanent ...