most people with bulimia eat large amounts of food then make themselves vomit or purge. typically, they will do this at least once a week or more often. bulimic people often think about how their bodies look, and usually, the motive behind purging is the want to be skinny. the person may also have anorexia nervosa. however, most with bulimia have a normal weight or are overweight, which makes it difficult to know when someone has bulimia from just simply looking at them. it is also common to have calluses or bruising on the fingers from purging.