Published: 18 Jun 2025

ICD9: 307.1      ICD10: F50.00      ICD11: 6B80

Anorexia Nervosa (often shortened to anorexia) is a serious and potentially life-threatening eating disorder characterized by an abnormally low body weight, an intense fear of gaining weight, and a distorted perception of body weight or shape.
It's more than just being worried about weight; it's a complex mental health condition with significant physical and psychological consequences.

Here's a breakdown of the key features:

Restriction of Energy Intake: Individuals with anorexia significantly restrict their food intake, leading to a body weight that is persistently below minimally normal or expected for their age, sex, developmental trajectory, and physical health. This can involve limiting the quantity and/or types of food consumed.

Intense Fear of Gaining Weight: The fear of gaining weight or becoming fat is a central feature. This fear is often persistent and does not diminish even when the individual is underweight.

Disturbed Body Image: Individuals with anorexia often have a distorted perception of their body weight or shape. They may see themselves as overweight even when they are severely underweight. They may also place undue importance on their weight or shape in their self-evaluation, or deny the seriousness of their low body weight.

Diagnostic Criteria (Simplified overview from the DSM-5):

A. Restriction of energy intake relative to requirements, leading to a significantly low body weight in the context of age, sex, developmental trajectory, and physical health. "Significantly low weight" is defined as less than minimally normal or, for children and adolescents, less than that minimally expected.

B. Intense fear of gaining weight or of becoming fat, or persistent behavior that interferes with weight gain, even though underweight.

C. Disturbance in the way in which one's body weight or shape is experienced, undue influence of body weight or shape on self-evaluation, or persistent lack of recognition of the seriousness of the current low body weight.

Important Considerations:

Severity: Anorexia Nervosa is categorized based on BMI (Body Mass Index) in adults. In children and adolescents, BMI percentile is used. The lower the BMI (or percentile), the more severe the condition.

Types (though the DSM-5 doesn't emphasize these):
Restricting Type: Weight loss is achieved primarily through dieting, fasting, and/or excessive exercise.
Binge-Eating/Purging Type: The individual engages in recurrent episodes of binge eating or purging behaviors (e.g., self-induced vomiting, misuse of laxatives, diuretics, or enemas). Note that individuals with this type are still significantly underweight; otherwise, a diagnosis of Bulimia Nervosa or Other Specified Feeding or Eating Disorder (OSFED) might be considered.

Physical and Psychological Consequences: Anorexia can have severe physical consequences, including:
Heart problems (e.g., slow heart rate, irregular heart rhythms, heart failure)
Bone loss (osteoporosis)
Muscle weakness
Gastrointestinal problems
Electrolyte imbalances
Amenorrhea (absence of menstruation in females)
Anemia
Kidney problems
Dry skin and hair loss
Increased risk of death

Psychologically, it's often associated with:
Depression
Anxiety (especially social anxiety)
Obsessive-compulsive disorder (OCD)
Perfectionism
Low self-esteem
Social isolation

Causes: The exact causes of anorexia are complex and not fully understood. It is likely a combination of genetic, biological, psychological, and sociocultural factors. Factors that may contribute include:
Genetics: There's evidence that eating disorders can run in families.
Brain chemistry: Imbalances in certain brain chemicals (neurotransmitters) may play a role.
Personality traits: Perfectionism, obsessive tendencies, and anxiety are often associated with anorexia.
Societal pressures: Cultural pressures to be thin can contribute to the development of the disorder.
Trauma: Past trauma can sometimes be a contributing factor.

Treatment: Treatment for anorexia typically involves a multidisciplinary approach, including:
Medical monitoring and stabilization: Addressing any immediate health risks due to malnutrition.
Nutritional rehabilitation: Gradually restoring weight and normalizing eating patterns.
Psychotherapy: Addressing the underlying psychological issues, such as distorted body image, anxiety, and low self-esteem. Cognitive Behavioral Therapy (CBT), Family-Based Therapy (FBT, especially for adolescents), and other therapies are often used.
Medication: Medications (e.g., antidepressants) may be used to treat co-occurring mental health conditions.
Family involvement: Family therapy is often an important part of treatment, especially for adolescents.

Important Note: Anorexia Nervosa is a serious and complex illness. If you or someone you know is struggling with symptoms of an eating disorder, it's essential to seek professional help from a qualified medical doctor, mental health professional, or registered dietitian. Early intervention can significantly improve the chances of recovery. Do not attempt to self-diagnose or self-treat.

Where to find help:

National Eating Disorders Association (NEDA): [https://www.nationaleatingdisorders.org/](https://www.nationaleatingdisorders.org/)
National Association of Anorexia Nervosa and Associated Disorders (ANAD): [https://anad.org/](https://anad.org/)
The Emily Program: [https://www.emilyprogram.com/](https://www.emilyprogram.com/)

These organizations can provide information, resources, and support for individuals and families affected by eating disorders.