The primary function of eating is to satisfy physical needs and a person is usually able to stop eating after feeling full. However, for people with bulimia nervosa and binge-eating disorder, their eating pattern is mostly driven by emotions rather than by physical hunger. They will use eating to satisfy psychological needs, such as venting or numbing emotions and avoiding stress. . People with bulimia nervosa and binge-eating disorder normally binge eat within a short period of time until they are uncomfortably full. Gradually, a vicious cycle is formed and eating becomes their only way to deal with emotions and stress. People with bulimia nervosa may perform health-harming compensatory behaviors after bingeing such as purging and abusing laxatives; while people with binge eating disorder may not have such kinds of compensatory behaviors but generally have problems with obesity.
For people with bulimia nervosa and binge eating disorder, they may provide a sense of distraction from their real world. When the eating behavior becomes out of control, it will cause physical, psychological and social impairments. Physically, patients may consume a large amount of high-caloric, high-fat and high-sugar food during their bingeing which may increase the tendency of obesity, and cardiovascular and gastrointestinal problems. If patients habitually adopt unhealthy compensatory behaviors after bingeing, such as purging or abusing laxatives, they may have side effects such as esophageal reflux or rupture, electrolyte disturbances, and constipation. Psychologically, repeated experience of loss of control may damage an individual’s self-image. The guilt and fear of becoming fat after bingeing may increase the risk of developing anxiety and depression. Most sufferers may isolate themselves from social situations in order to conceal their problems and avoid being judged by others.