How is it that eating disorders start?

Rewarding: At some point, all maladaptive behavior that is maintained was reinforced/rewarded. Be it a reward of removing something painful (e..G, feeling out of control & exerting control not eating; removing guilt from binging through purging) or adding something pleasurable (e.g., receive complements for loss of weight). Nearly all behavior results from genetics + environment + experience + reward.

Perfect storm: Typically anorexia, bulimia, &/or binge eating disorders develop as a means for coping with stressors. I often describe it as the perfect storm of symptoms and environmental stress. Pica and other a-typical eating disorders are something very different. In regard to anorexia, bulimia, & BED, there is often issues of control over the chaos perceived in one's life (the storm).