Anorexia nervosa, bulimia nervosa and binge eating, the three main types of eating disorder, are most commonly associated with psychological illness but do not stem from one single cause. Although concerns about weight and body image may play some part in the development of eating disorders, the actual causes are generally attributable to emotional difficulties, personality disorders and social or cultural pressures which the sufferer finds unmanageable.
In the case of anorexia nervosa, sufferers either starve themselves or restrict hugely their intake of food and are intensely preoccupied with not putting on weight. Their perceptions of their size and weight are normally extremely distorted.
Bulimia nervosa, on the other hand, is characterised by binge eating followed by self-induced vomiting or taking laxatives and, like anorexia, sufferers live in fear of becoming fat.
Binge eating, which involves consuming excessive quantities of food within very short spaces of time, is not followed by any kind of compensatory behaviour such as vomiting, exercise or laxative abuse and so quite often leads to obesity, although not necessarily so. Rather than being prompted by hunger, a binge eaterâ€™s behaviour is generally caused by emotional upset or depression.