Bulimia is a related eating disorder in which patients engage in repeated bouts of overeating (binges) followed by behaviors designed to prevent weight gain (purges). Self-induced vomiting is the classic example of purging, but purging behaviors include a wide variety of activities including abuse of laxatives or diet pills, long bouts of restriction, and exercise to the point of medical instability.
Recent genetic studies have found that patients with Bulimia often have problems in their satiety system. Satiety refers to all of the signals from the body that tell the brain to stop eating after starting a meal. Many patients with Bulimia have a decreased ability to feel satiated after a meal even if they are uncomfortably full. This disconnect between the physical discomfort of overeating while the brain still feels hungry produces intense anxiety that can only be relieved by the act of purging in an attempt to align mind and body again.