When you bleach your hair, the melanin in the hair shaft is broken down or to put it scientifically, the bleach oxidizes the melanin, causing the melanin to lose its colour and makes the hair appear its natural colour,a pale yellow. Bleaching your hair frequently will result in more and more damage. Don’t bleach your hair more than once every 2 months or so. Improper bleaching can result in hair breakage and hair loss. For bleached hair you should be using sulfate-free shampoo.