"I'm Fat' the most overused phrase by young women...but who takes it too far?

Body dysmorphic disorder is a condition that someone obsessing , which are distressing thoughts that repeatedly intrude into a person's awareness. With BDD, the distressing thoughts are about perceived appearance flaws. A person could be attractive, but in their head they see a distorted image of a monster

http://kidshealth.org/teen/your_mind/body_image/body_image_problem.html