What is anorexia nervosa?


Anorexia nervosa is one of the most common eating disorders, characterised by persistent attempts to lose weight, weight loss, inappropriate preoccupation with food and weight, bizarre behaviour with food, intense fear of gaining weight, and amenorrhoea.


Anorexia can be a major symptom of internal and external medical conditions such as cancer and tuberculosis, and it can also be a symptom of mental health conditions such as anorexia nervosa or depression.

It can also occur in the elderly without any specific cause, as a result of declining physical fitness.


Symptoms usually begin between the ages of 10 and 30.

There is a strong fear of weight gain and obesity and indifference or resistance to treatment.

Inappropriate eating behaviours associated with weight loss are often secretive, and there is a reluctance to eat with family or in public.

The term anorexia is misleading, as actual decreased appetite is not common until late in the disease. Binge eating is sometimes involved, usually in secret and often at night. Binge eating is often followed by self-induced vomiting or purging behaviour using laxatives.

Laxatives and diuretics are often abused and significant amounts of exercise are habitual.

Inappropriate behaviour around food is common, such as hiding food throughout the house.

If the weight loss is severe, a variety of internal medical problems may occur, including hypothermia, amenorrhoea, oedema, and low blood pressure.


The diagnosis is made through an examination by a psychiatrist, history taking, and a question and answer process. A diagnosis of anorexia nervosa can be made if the following symptoms are present

DSM-5 Diagnostic Criteria for Anorexia Nervosa

A. The individual maintains a body weight that is below the minimum normal level for physical health in light of age, sex, and developmental trajectory.

B. Individuals with this disorder typically exhibit an intense fear of weight gain

C. The individual’s experience and meaning of weight and body shape is impaired.

After diagnosing anorexia nervosa, the disorder is subdivided into restrictive and binge and purge types as follows

(1) Restrictive: Binge or purge behaviours (i.e., spontaneous vomiting, laxative abuse, diuretics, or enemas) have not been regular in the past 3 months.

(2) Binge/purge type: recurrent binge or purging behaviour in the last three months.

Testing and differential diagnosis for other conditions that can cause weight loss, such as brain tumours or cancer, should be done.

Psychiatric consultation and examination is essential to differentiate from other neuropsychiatric disorders and to obtain an accurate assessment of current general health status.


Treatment of anorexia nervosa usually involves a multidisciplinary approach. Initially, outpatient treatment is recommended, but inpatient treatment is indicated for patients who do not respond to outpatient treatment, are at high physical risk, or lack psychosocial resources. Concurrent treatment of the patient and family is effective, and appropriate pharmacological treatment should be considered in addition to psychotherapeutic approaches.


The course of anorexia nervosa varies from spontaneous recovery to death due to severe complications. The overall prognosis is not favourable, with a mortality rate of 5-18%.

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