What is Anorexia Nervosa?

Anorexia nervosa typically begins around puberty, but can occur at any age. It is a life threatening mental illness characterized by, over a period of at least three months:

1. Persistent behaviours that interfere with maintaining an adequate weight for health. These behaviours may include: restricting food, compensating for food intake through intense exercise, and/or purging through self-induced vomiting or misuse of medications like laxatives, diuretics, enemas, or insulin. 
   Anorexia nervosa was previously associated specifically with weight loss, making it difficult to recognize in children and adolescents. Children and adolescents need to gain weight in order to support healthy growth and development, so failing to gain weight or grow is just as concerning as weight loss;
   
   
2. A powerful fear of gaining weight or becoming fat. The individual may feel this way even if they are maintaining a weight that is too low for their health. Their fear may translate into the use of a variety of techniques to evaluate their body size or weight – behaviours known as body checking. These techniques can include frequent weighing, obsessive measuring of body parts and the persistent use of mirrors to check for “fat.” It is important to note that weight loss or a lack of weight gain rarely calms body anxieties;
   
   
3. Disturbance in how the person experiences their weight and shape. The person overestimates their body size, usually evaluates it negatively, and may feel their weight and shape matter more than most anything else about them; and
   
   
4. The person does not fully appreciate the seriousness of their condition. Anorexia is linked with cardiac arrest, suicidality, and other causes of death.

Note: 

Anorexia nervosa was previously associated with the loss of menstrual periods which made it difficult or impossible to identify in prepubescent youth or individuals who do not menstruate – this aspect is no longer necessary for diagnosis. 

Atypical anorexia nervosa shares the same characteristics as anorexia nervosa; however, the person’s weight is within or above the “average” range for age and height. This could occur, for instance, when a person starts at a higher weight and drops weight to the point that they are experiencing cardiac instability.

Common Co-Occurring Illnesses

The individual experiencing an eating disorder may also be affected by other mental illnesses, including: 

• Depression or depressed mood
• Anxiety (including generalized or social anxiety)
• Obsessive-compulsive disorder
• History of trauma or post-traumatic stress disorder

Anorexia nervosa may also be associated with self-harm and suicidality.