What Are Eating Disorders?
Eating disorders are mental health conditions characterised by persistent disturbances in eating behaviour — including restriction of food intake, binge eating, purging, or other compensatory behaviours — accompanied by significant distress and impairment. They involve complex disturbances in how a person relates to food, their body, and themselves.
Eating disorders are not lifestyle choices, phases, or expressions of vanity. They are serious conditions with significant psychological, physical, and social consequences. They frequently co-occur with anxiety disorders, depression, OCD, trauma, and substance use disorders.
Eating disorders affect people of all genders, ages, ethnicities, and body sizes. While they are more prevalent in women and typically onset in adolescence or young adulthood, they are significantly underdiagnosed in men, older adults, and people of colour.
Types of Eating Disorders
Anorexia Nervosa
Anorexia nervosa is characterised by persistent restriction of energy intake leading to significantly low body weight, intense fear of gaining weight or becoming fat, and a disturbance in the way one's body weight or shape is experienced. It has the highest mortality rate of any mental health condition, with deaths occurring from medical complications of starvation and from suicide.
Two subtypes are recognised: the restricting type (weight loss achieved through dieting, fasting, and/or excessive exercise) and the binge-eating/purging type (weight loss achieved through binge eating and/or purging behaviours).
Bulimia Nervosa
Bulimia nervosa is characterised by recurrent episodes of binge eating (eating a large amount of food in a discrete period with a sense of loss of control) followed by compensatory behaviours to prevent weight gain — most commonly self-induced vomiting, but also misuse of laxatives, diuretics, fasting, or excessive exercise. Self-evaluation is unduly influenced by body shape and weight.
Binge Eating Disorder (BED)
Binge Eating Disorder is the most common eating disorder. It is characterised by recurrent episodes of binge eating accompanied by marked distress, without the regular use of compensatory behaviours seen in bulimia nervosa. BED is associated with significant psychological distress and physical health consequences.
Avoidant/Restrictive Food Intake Disorder (ARFID)
ARFID involves an eating or feeding disturbance — such as apparent lack of interest in eating, avoidance based on sensory characteristics of food, or concern about aversive consequences of eating — that results in significant nutritional deficiency or functional impairment. Unlike anorexia, ARFID is not driven by concerns about body weight or shape.
Other Specified Feeding or Eating Disorders (OSFED)
OSFED covers presentations that cause significant distress and impairment but do not meet the full criteria for the above diagnoses. This includes atypical anorexia nervosa (where all criteria for anorexia are met but weight is within or above the normal range), purging disorder, and night eating syndrome.
Symptoms and Warning Signs
Behavioural Signs
- Significant restriction of food intake or avoidance of certain foods
- Eating large amounts of food in a short period
- Disappearing to the bathroom after meals
- Excessive exercise, particularly when unwell or in bad weather
- Wearing loose clothing to hide body shape
- Rituals around food (cutting food into small pieces, eating in a specific order)
- Avoidance of social eating situations
- Hoarding or hiding food
Psychological Signs
- Preoccupation with food, weight, calories, or dieting
- Intense fear of weight gain
- Distorted body image — perceiving oneself as larger than one is
- Extreme dissatisfaction with body shape or weight
- Mood disturbance linked to eating or body image
- Perfectionism and rigid thinking
Physical Signs
- Significant weight loss or fluctuating weight
- Fatigue, dizziness, and fainting
- Hair loss or growth of fine body hair (lanugo)
- Dental erosion (from purging)
- Swollen cheeks or jaw (from purging)
- Calluses on knuckles (from self-induced vomiting)
- Menstrual irregularities or loss of menstruation
- Gastrointestinal problems
Causes and Risk Factors
Genetic and Neurobiological Factors
Eating disorders have a significant genetic component. Twin studies suggest heritability of 50–80% for anorexia nervosa. Neurobiological research has identified differences in serotonin, dopamine, and reward processing systems. Temperamental traits associated with eating disorders — perfectionism, anxiety, and harm avoidance — also have genetic components.
Psychological Risk Factors
- Perfectionism and high personal standards
- Anxiety and obsessive-compulsive traits
- Low self-esteem and negative body image
- History of trauma or abuse
- Dieting history — particularly early or extreme dieting
- History of weight-related teasing or bullying
Social and Cultural Risk Factors
- Cultural pressures around body weight and shape
- Exposure to idealised body images in media and social media
- Participation in weight-sensitive sports or activities (gymnastics, ballet, wrestling)
- Family history of eating disorders, dieting, or weight-related concerns
When to Seek Professional Help
Seek professional help if:
- You are significantly restricting your food intake
- You are binge eating and/or purging
- Your relationship with food and your body is causing significant distress
- You are experiencing physical symptoms related to your eating
- You are concerned about a family member's eating behaviour
A GP is a good first point of contact and can assess both the physical and psychological dimensions of eating disorders. Under the National Health Act (Section 6), you have the right to be informed about your condition and to participate in decisions about your care.