I can distinctly say that the ED behavior started at 12. I was a fat kid, a really fat kid, and I come from a really fat family but for some reason I was the only one who got crap for it (because I'm the only girl maybe? I have no idea). Probably around age 8 or 9 it started to bother me, and by 12 I just decided I'd rather die than spend another day being fat. And that was that. Anorexia at first, then bulimia. I'm the bulimic always trying to be anorexic and failing miserably. So it goes.