Bulimia nervosa Health Article

Definition

Bulimia nervosa is an eating disorder characterized by binge eatingand engaging in inappropriate ways of counteracting the bingeing (using laxatives, for example) in order to prevent weight gain. The word "bulimia" is the Latin form of the Greek word boulimia, which means "extreme hunger." A binge is consuming a larger amount of food within a limited period of time than most people would eat in similar circumstances. Most people with bulimia report feelings of loss of control associated with bingeing, and some have mildly dissociative experiences in the course of a binge, which means that they feel disconnected from themselves and from reality when they binge.

The handbook for mental health professionals to aid in diagnosisis the Diagnostic and Statistical Manual of Mental Disorders, also known as the DSM-IV-TR.This book categorizes bulimia nervosa as an eating disorder, along with anorexia nervosa.

Description

Bulimia nervosa is classified into two subtypes according to the methods used by the patient to prevent weight gain after a binge. The purging subtype of bulimia is characterized by the use of self-induced vomiting, laxatives, enemas, or diuretics (pills that induce urination); in the nonpurging subtype, fasting or overexercising is used to compensate for binge eating.

The onset of bulimia nervosa is most common in late adolescence or early adult life. Dieting efforts and body dissatisfaction, however, often occur in the teenage years. For these reasons, it is often described as a developmental disorder. Although genetic researchers have identified specific genes linked to susceptibility to eating disorders, the primary factor in the development of bulimia nervosa is environmental stressrelated to the onset of puberty. Girls who have strongly negative feelings about their bodies in response to puberty are at high risk for developing bulimia.

The binge eating associated with bulimia begins most often after a period of strict dieting. Most people with bulimia develop purging behaviors in response to the bingeing. Vomiting is used by 80%–90% of patients diagnosed with bulimia. The personal accounts of recovered bulimics suggest that most "discover" vomiting independently as a way of ridding themselves of the food rather than learning about it from other adolescents. Vomiting is often done to relieve an uncomfortable sensation of fullness in the stomach following a binge as well as to prevent absorption of the calories in the food. Vomiting is frequently induced by touching the gag reflex at the back of the throat with the fingers or a toothbrush, but a minority of patients use syrup of ipecac to induce vomiting. About a third of bulimics use laxatives after binge eating to empty the digestive tract, and a minority use diuretics or enemas. Purging behaviors lead to a series of digestive and metabolic disturbances that then reinforce the behaviors.

A small proportion of bulimics exercise excessively or fast after a binge instead of purging.

Patients with bulimia may come to the attention of a psychiatristbecause they develop medical or dental complications of the eating disorder. In some cases, the adolescent's dentist is the "case finder." In many cases, however, the person with bulimia seeks help.

Causes

As of 2002, bulimia nervosa is understood to be a complex disorder with multiple factors contributing to its development. Researchers presently disagree about the degree of influence exerted by genetic factors, psychological patterns in the family of origin, and social trends.

GENETIC.Two recently published reviews (in 1999 and 2000) suggest that there is some heritability for bulimia. In other words, these articles suggest that there is a genetic component to bulimia. Neurotransmittersare chemicals that pass chemical messages along from nerve cell to nerve cell, and people with bulimia have abnormal levels of certain neurotransmitters. Some observers have suggested that these abnormalities in the levels of central nervous system neurotransmitters may also be influenced by genetic factors.

FAMILY OF ORIGIN.A number of recent studies point to the interpersonal relationships in the family of origin (the patient's family while growing up) as a factor in the later development of bulimia. People with bulimia are more likely than people with anorexia to have been sexually abused in childhood; studies have found that abnormalities in blood levels of serotonin (a neurotransmitter associated with mood disorders) and cortisol (the primary stress hormone in humans) in bulimic patients with a history of childhood sexual abuseresemble those in patients with post-traumatic stress disorder. Post-traumatic stress disorder is a mental disorder that can develop after someone has experienced a traumatic event (horrors of war, for example) and is unable to put that event behind him or her— the disorder is characterized by very realistic flashbacks of the traumatic event.

A history of eating conflicts and struggles over food in the family of origin is also a risk factor for the development of bulimia nervosa. Personal accounts by recovered bulimics frequently note that one or both parents were preoccupied with food or dieting. Fathers appear to be as influential as mothers in this regard.

An additional risk factor for early-onset bulimia is interest in or preparation for a sport or occupation that requires strict weight control, such as gymnastics, figure skating, ballet, and modeling.

SOCIOCULTURAL CAUSES.Emphasis in the mass media on slenderness in women as the primary criterion of beauty and desirability is commonly noted in studies of bulimia. Historians of fashion have remarked that the standard of female attractiveness has changed over the past half century in the direction of greater slenderness; some have commented that Marilyn Monroe would be considered "fat" by contemporary standards. The ideal female figure is not only unattainable by the vast majority of women, but is lighter than the standards associated with good health by insurance companies. In 1965 the average model weighed 8% less than the average American woman; as of 2001 she weighs 25% less.

Another factor mentioned by intellectual historians is the centuries-old split in Western philosophy between mind and body. Instead of regarding a human person as a unified whole comprised of body, soul, and mind, Western thought since Plato has tended to divide human nature in a dualistic fashion between the life of the mind and the needs of the body. Furthermore, this division was associated with gender symbolism in such a way that the life of the mind was associated with masculinity and the needs of the body with femininity. The notion that the "superior" mind should control the "inferior" physical dimension of human life was correlated with men's physical, legal, and economic domination of women. Although this dualistic pattern of symbolic thought is no longer a conscious part of the Western mindset, it appears to influence Western culture on a subterranean level.

A number of different theories have been put forward to explain the connections between familial and social factors and bulimia. Some of these theories maintain that:

• Bulimia results from a conflict between mother and daughter about nurturing and dependency. Girls are typically weaned earlier than boys and fed less. The bulimic's bingeing and purging represent a conflict between wanting comfort and believing that she does not deserve it.
• Bulimia develops when an adolescent displaces larger conflicts about being a woman in a hypersexualized society onto food. Many writers have commented about the contradictory demands placed on women in contemporary society— for example, to be sexually appealing yet "untouchable" at the same time. Controlling body size and food intake becomes a simplified solution to a very complex problem of personal identity and moral standards.
• Bulimia is an obsessionwith food that the culture encourages in order to protect men from competition from intellectually liberated women. Women who are spending hours each day thinking about food, or bingeing and purging, do not have the emotional and intellectual energy to take their places in the learned professions and the business world.
• Bulimia expresses a fear of fat rooted in childhood memories of mother's size relative to one's own.
• Bulimia results from intensified competition among women for professional achievement (getting a desirable job or a promotion, or being accepted into graduate or professional school) as well as personal success (getting a husband), because studies have indicated that businesses and graduate programs discriminate against overweight applicants.
• Bulimia results from attempts to control emotional chaos in one's interpersonal relationships by imposing rigid controls on food intake.

Nutrition experts have pointed to the easy availability of foods high in processed carbohydrates in developed countries as a social factor that contributes to the incidence of bulimia. One study found that subjects who were given two slices of standard mass-produced white bread with some jelly had their levels of serotonin increased temporarily by 450%. This finding suggests that bulimics who binge on ice cream, bread, cookies, pizza, and fast food items that are high in processed carbohydrates are simply manipulating their neurochemistry in a highly efficient manner. The incidence of bulimia may be lower in developing countries because dietsthat are high in vegetables and whole-grain products but low in processed carbohydrates do not affect serotonin levels in the brainas rapidly or as effectively.