Eating Disorders



An eating disorder is a mental health condition in which a person can use the control of food, and at times their weight, as a means to try to cope with difficult situations and feelings.

Eating disorders are most common between 13-17 years old but can occur in any age group. They affect both males and females, can often be kept secretive and not everyone with an eating disorder is underweight.

With treatment most people can recover but this can be a life threatening illness - anorexia nervosa in particular carries one of the highest mortality figures for any psychiatric disorder. Recognition and timely management is therefore vital.

Signs and symptoms

Eating disorders include:

  1. Anorexia Nervosa – Characterised by: low BMI <18.5kg/m2 OR rapid weight loss of >20% of total body weight within a 6 month period, restriction of nutritional intake, sometimes vomiting, excessive exercise, use of appetite suppressants or diuretics, fear of gaining weight, disturbance in body image. Endocrine dysfunction inclduing amenorrhoea, loss of libido, delayed puberty in children.  
  2. Bulimia Nervosa – Characterised by: Recurrent episodes of binge eating, preoccupation with food, feeling loss of control, preventing weight gain by use of laxatives, diuretics, other medications and excessive exercise. There may also be a history of anorexia nervosa and atypical anorexia nervosa.
  3. Binge Eating Disorder
  4. Atypical Eating Disorders
  5. Avoidant Restrictive Food Intake Disorder (ARFID)


  • Full psychiatric history and screening of risk level – is there an urgent need for crisis services? Consider other mental health conditions and/or co-existing personality disorders
  • Record weight, height, BMI and date taken (must be within 1-2 weeks of referral)
  • Complete physical observations, physical examination and consider need for other investigations e.g. ECG
  • Complete baseline bloods (must be within month of referral): FBC, U+E, Urea,TCO2, LFTs, TFTs, Calcium, Phosphate, Magnesium, Glucose
  • Consider (but do not limit assessment) to use of screening tools such as SCOFF

If following initial assessment it is felt that patient meets criteria for an eating disorder refer straight away for age appropriate eating disorders service input for ongoing management (CAMHS for under 18s).

If any of the following are present make an URGENT referral:

  • BMI <15
  • BMI <15 and losing >1kg per week
  • Pregnant
  • Insulin dependent diabetic
  • Medical complications as result of eating disorder (specify)
  • Psychiatric co-morbidities



In a medical inpatient context it is important to use urgent blood/ECG investigations to determine and firstly treat any potentially life threatening complications:

  • Severe dehydration
  • Controlled and extremely cautious replacement of electrolyte disturbance including low potassium/phosphate/sodium/calcium/glucose and albumin
  • Cardiac abnormalities such as arrhythmias/QTc prolongation
  • Hypothermia

Long-term management is predominantly through psychological therapies e.g. targeted CBT. Robust psycho education, for patient and family, should be provided as well as signposting to support organisations. Medication may be used though not in isolation.  

Editorial Information

Last reviewed: 03/04/2024

Next review date: 02/04/2025

Author(s): Core Trainee in Psychiatry, NHS Lothian & Medical Education Fellow, NHS Lothian.

Author email(s):

Approved By: NHSGGC MyPsych Editorial Board

Reviewer name(s): NHSGGC MyPsych Editorial Board.