Patients assume that purging is an effective means of expunging calories consumed during binge-eating episodes. (See pp. 172-173 for information on calories retained after purging.) The emptiness they experience after vomiting provides the evidence that this is, indeed, true. It is not uncommon for patients to report that initially purging helped them lose weight despite significant binge-eating episodes. Over time, however, most patients who continue to purge find that body weight does increase. Usually purging is part of a cycle of bingeing and purging. Some patients binge and purge multiple times per occurrence. Other patients purge normal-sized meals; some purge if they feel even slightly full or if they have eaten something they feel is fattening; and still others purge everything they eat.