The term eating disorder covers a range of unique mental illnesses that involve disordered eating behavior. The one issue all eating disorders have in common- besides a lack of control over eating habits- is that they can progress and cause serious, even permanent damage to your mental and physical health. But even though they are serious illnesses, eating disorders are treatable. Eating disorders may be caused by several factors. These include genetics, brain biology, personality traits, and cultural ideals. Any two people with the same eating disorder can have somewhat different symptoms and experiences. It’s also possible for someone to move between diagnoses if their symptoms change – there is often a lot of overlap between different eating disorders.