Eating disorders: Anorexia and bulimia
An update on eating disorders. Eating disorders such as anorexia nervosa and bulimia can threaten psychological well being, physical health, and sometimes even life itself.
In all cases, sufferers have a preoccupation with food, a distorted body image and eating behaviours that are out of control.
Anorexia nervosa is a life-threatening disorder that involves self-induced starvation and refusal to eat to maintain normal healthy weight for height.
Although anorexic patients have an appetite, it is suppressed by their rigid control of eating because of their obsessive fear of weight gain. Over 90 per cent of sufferers are women and the prevalence of anorexia is estimated to be 0.5 - 3.7 per cent .
Anorexics tend to be affluent, perfectionist and high achievers. Sufferers also tend to be depressed, withdrawn socially and reluctant to express their feelings.
The act of strict dieting provides an illusion of control and anorexics can develop strange rituals around eating, often refusing to eat in the presence of others. . Patients have an abnormal weight loss of 15 per cent or more of their body weight.
The physical signs of starvation include brittle nails and hair, dry skin, feeling cold and, in women, menstrual problems.
A more common eating disorder is Bulimia nervosa, being two to three times more prevalent than anorexia. Bulimia nervosa sufferers typically consume large quantities of food (up to 5000 kilocalories) and then rid their body of the excess calories by vomiting, the abuse of laxatives or diuretics.
This "binge and purge" behaviour is often hidden because sufferers eat normally in public and the eating disorder is kept secret.
Physical signs include the erosion of tooth enamel caused by the acidity of vomit, a puffy face due to swollen salivary glandsscars and abrasions on the fingers caused by self-induced vomiting and dehydration.
Looking for the cause
The onset of eating disorders is often associated with a stressful life event such as entering a new school, lack of independence or with an emotionally troubled family environment.
Female athletes are often more vulnerable to eating disorders than the general population, particularly in sports where low body weight and fat level are perceived to be an advantage, such as gymnastics, ballet and long-distance running.
Eating disorders are primarily psychological. People with eating disorders experiment with various weight control diets and it has been suggested that dieting itself may be causative. It is now accepted that dieting is a feature of the disorder but not a cause.
Some studies have shown that there may be a genetic factor in the development of both anorexia and bulimia . Scientists are studying various genes that may interact with the environment and other factors to increase susceptibility Biochemical imbalances of the brain chemicals called neurotransmitters, which control appetite, moods and sleeping patterns may also be involved.
Early diagnosis is essential and treatment involves a comprehensive plan of medical care, psychosocial interventions, nutritional counselling and sometimes medication management.
The main treatment aim is to gradually and gently restore normal food behaviour and body weight and provide a sense of control and increased self-esteem.
Despite the complexities of eating disorders, sufferers have an excellent chance of a complete recovery, especially if the illness is recognised early.
References 1. National Institute of Mental Health (2001) Eating disorders: Facts about Eating Disorders and the Search for Solutions. NIH Publication No. 01-4901
2. Strober M, Freeman R, Lampert C, Diamond J, Kaye W. (2000). Controlled family study of anorexia nervosa and bulimia nervosa: evidence of shared transmission of partial syndromes. Amer J. Psych. 157(3): 393-401.
References: European Food Information Council (EUFIC) Date last updated: 17 November 2006