A person with bulimia nervosa exhibits a preoccupation with food and often secretly binge eats. A binge is an amount of food that is definitely larger than most people would eat over a similar period of time and under similar circumstances (eg, most people will overeat on vacation). Bingers also exhibit a lack of control over eating during the episode, calorie intake ranging from 3,000 to 40,000 per episode. The incidence of this disorder is unknown, since it is secretive and is kept hidden by fear or shame. Bulimia nervosa often begins in adolescence, but recorded incidences range from ages 5 to 70.
Binge eating episodes are followed by various forms of purging. Vomiting can be induced by inserting a finger or other object down the throat. After a while, it may no longer be necessary to induce vomiting. The person will verify that everything ingested has been vomited before completing the purge. The immediate aftermath feelings are one of relief, of power, of being able to overeat but avoiding the consequences, of “winning” and fooling everyone. One young woman reported: “It’s the one thing my father can’t control.” These feelings are positively reinforced and help explain why the disorder continues. However, negative feelings such as self-hatred, self-hatred, fear of being found out, guilt, and being out of control follow the positive ones. Bulemics often promise never to do this again.
Other forms of purging include laxatives (typically 2 to 30 laxatives per use), diuretics, diet pills, or enemas. These methods do not achieve weight loss, but the feeling of getting rid of the intake is still satisfying and empowering. Non-purging methods include excessive exercise (up to five hours per day), which can be rationalized as physical fitness. Fasting, an attempt to compensate for excessive eating, is counterproductive in the sense that it causes bingeing again when the person feels hungry.
Physical ramifications of binge eating followed by purging can include swollen salivary glands, broken blood vessels in the eyes, ruptured stomach, esophageal tears, dehydration, electrolyte imbalance (which compromises heart function), and malnutrition. Because vomiting erodes the enamel on the inside of the teeth, an eight-year-old bulimic reports that dental repairs cost $10,000.
Bulimia nervosa has several causative factors. A biological factor points to serotonin in the brain and its regulation of satiety and food preferences, as well as in impulse regulation. Approximately 85% of bulimic patients suffer from hypoglycemia (low blood sugar), which can contribute to the urge to binge eat; over time, the behavior develops addictive qualities. A multilevel model for the aetiology of bulimia nervosa includes social, cultural, family and personal factors: society overvalues thinness and obesity is highly stigmatized; bulimic families express increased anger, aggression, and conflict (no conflict resolution skills), indirect communication, lack of support, and lack of economy; over-attention to food and weight in the family (the degree of symptoms is associated with the occurrence between mothers and sisters); excessive concern for pleasing others; strong peer group influences to be attractive (thin), gain the approval of other women, and attract boyfriends; feeling of inefficiency and low interoceptive awareness, generating high anxiety; a disconnection from unpleasant feelings by diverting attention to food. Bulimics may display other impulsive behaviors, such as drinking, sexual promiscuity, kleptomania, excessive spending, and drug use.