What is an eating disorder?

Eating disorders are serious mental health conditions characterised by abnormal eating behaviours, thoughts, and emotions. These significantly impact an individual's physical health and psychological well-being, and therefore their overall quality of life. Eating disorders often involve a preoccupation with food, body weight and shape, as well as distorted perceptions of body image. These disorders can affect people of all ages, genders, and backgrounds, and they often co-occur with other mental health conditions such as depression, anxiety, or substance abuse.

There are several types of eating disorders that have been identified and classified, including: anorexia nervosa; bulimia nervosa; binge eating disorder (BED); feeding or eating disorder not elsewhere categorised (FEDNEC) and avoidant/restrictive food intake disorder (ARFID). Each one, while similar in some respects to the others, is different and requires a different approach to resolve the disorder.

Anorexia nervosa

Anorexia nervosa is characterised by an intense fear of gaining weight and a distorted body image, leading to restrictive eating behaviours and significant weight loss. 

Key features of anorexia nervosa include:

Restricted food intake

People with anorexia nervosa severely limit their food intake, often by restricting the amount and types of food they eat. They may meticulously count calories, avoid specific food groups, or adopt extreme dieting behaviours.

Intense fear of weight gain

An overwhelming fear of gaining weight or becoming fat is a central aspect of anorexia nervosa. This fear persists even when individuals are significantly underweight, leading to continual efforts to control their weight through restrictive eating.

Distorted body image

Individuals with anorexia nervosa have a distorted perception of their body size and shape. They may see themselves as overweight or obese, despite being severely underweight. 

Physical complications

Anorexia nervosa can result in serious physical health consequences due to malnutrition and inadequate food intake. These complications can include extreme weight loss, nutritional deficiencies, electrolyte imbalances, gastrointestinal problems, cardiovascular issues, osteoporosis, and hormonal disturbances.

Psychological effects

Beyond the physical symptoms, anorexia nervosa can also lead to psychological distress including depression, anxiety, obsessive-compulsive behaviours, social withdrawal, and a preoccupation with food, weight, and body image.

Impact on functioning

Anorexia nervosa can also significantly impair an individual's ability to function in various areas of life including relationships, school or work performance, and daily activities. The condition can also strain interpersonal relationships and lead to social isolation.

Bulimia nervosa 

Bulimia nervosa is characterised by recurrent episodes of binge eating followed by compensatory behaviours such as self-induced vomiting, misuse of laxatives, and excessive exercise to prevent weight gain.

Key features of bulimia nervosa include:

Binge eating

Episodes of binge eating involve consuming a large amount of food within a short, discrete period while feeling a loss of control over eating. Binge episodes are often triggered by emotional distress or a sense of stress, and individuals may eat rapidly and in secret.

Compensatory behaviours

Following binge eating episodes, individuals with bulimia nervosa engage in compensatory behaviours to counteract the perceived effects of overeating and prevent weight gain. These behaviours may include self-induced vomiting, misuse of laxatives, diuretics, or enemas, fasting, or excessive exercise.

Preoccupation with body weight and shape

Individuals with bulimia nervosa are intensely preoccupied with their body weight, shape, and appearance. They may have a distorted perception of their body size and shape, often equating self-worth with their body weight or shape.

Shame and guilt

Feelings of shame, guilt, and self-disgust are common following binge eating episodes in bulimia nervosa. These negative emotions can perpetuate the cycle of binge eating and compensatory behaviours, contributing to the maintenance of the disorder.

Physical and psychological consequences

Bulimia nervosa can have serious physical and psychological consequences. Physical complications may include electrolyte imbalances, dehydration, gastrointestinal problems, dental erosion and cardiovascular issues. Psychological effects may include depression, anxiety, low self-esteem, and social isolation.

Impact on functioning

Bulimia nervosa can significantly impair an individual's ability to function in various areas of life including relationships, school or work performance, and daily activities. The disorder can also lead to secrecy around eating and social withdrawal, making it challenging for individuals to seek help or support.

Binge eating disorder (BED)

Binge eating disorder (BED) is characterised by recurrent episodes of binge eating, where an individual consumes a large amount of food in a short period while feeling a loss of control over their eating. BED is, associated with significant emotional distress, shame, and guilt related to the binge eating episodes.

Key features of binge eating disorder include:

Recurrent binge eating episodes

Individuals with BED experience recurrent episodes of binge eating, typically occurring at least once a week for three months or more. During these episodes, they eat large quantities of food rapidly, often to the point of discomfort or physical pain, while feeling a sense of loss of control over their eating.

Absence of compensatory behaviours

Unlike bulimia nervosa, individuals with BED do not engage in regular compensatory behaviours such as self-induced vomiting, misuse of laxatives, or excessive exercise to offset the effects of binge eating. After a binge episode, they may experience feelings of guilt, shame, or distress.

Emotional and psychological impact

Binge eating disorder is often associated with significant emotional distress, including feelings of guilt, shame, and low self-esteem related to their binge eating episodes. Individuals may also experience symptoms of depression, anxiety, and other mental health concerns.

Preoccupation with food

Individuals with BED may have a persistent preoccupation with food, eating, and body weight. They may spend a significant amount of time thinking about food, planning future binges, or feeling anxious about their eating habits.

Physical health consequences

Binge eating disorder can have serious physical health consequences, including obesity, diabetes, high blood pressure, high cholesterol, gastrointestinal issues, and cardiovascular problems. These health issues may result from the excessive consumption of food during binge episodes and the associated weight gain.

Impact on functioning

BED can significantly impair an individual's ability to function in various areas of life, including relationships, work or academic performance, and social activities. The disorder may lead to social isolation, withdrawal, and difficulties in coping with daily life stresses.

FEDNEC (feeding or eating disorder not elsewhere categorised)

FEDNEC includes eating disorders that do not meet the criteria for anorexia nervosa, bulimia nervosa, or binge eating disorder but still cause significant distress or impairment. It serves as a catch-all category for individuals whose symptoms may not neatly fit into the criteria for other eating disorders but who still struggle with disordered eating patterns or attitudes toward food, body image, or weight that significantly affect their psychological and physical well-being

Examples of presentations that might fall under FEDNEC include:

• Purging disorder: Engaging in recurrent purging behaviours (such as vomiting or misuse of laxatives) without meeting the criteria for bulimia nervosa.
• Night eating syndrome: Consuming a significant portion of daily food intake during nighttime awakenings, often accompanied by insomnia or other sleep disturbances.
• Other atypical eating patterns: This could include irregular or unusual eating behaviours, such as chewing and spitting out food, extreme pickiness or avoidance of certain foods, or ritualised eating habits that do not fit the criteria for other specific eating disorders.
• Subthreshold binge eating disorder: Engaging in binge eating episodes that do not occur with the frequency or intensity required for a diagnosis of binge eating disorder but still cause distress or impairment.

Avoidant/restrictive food intake disorder (ARFID)

ARFID is characterised by an apparent lack of interest in eating or avoiding certain foods, leading to significant nutritional deficiencies, weight loss, and impaired growth in children. Unlike other eating disorders, individuals with ARFID are not primarily motivated by concerns about body weight or shape, but rather by sensory sensitivity, fear of negative consequences associated with eating, or a lack of interest in food.

Key features of avoidant/restrictive food intake disorder (ARFID) include:

Avoidance or restriction of food

Individuals with ARFID may have an aversion to certain food textures, tastes, colours, or smells, leading them to avoid a wide range of foods. They may also restrict their food intake due to a fear of choking, vomiting, or other negative consequences associated with eating.

Nutritional deficiencies

Avoidance or restriction of certain foods can result in inadequate nutrient intake, leading to nutritional deficiencies and impaired growth and development, particularly in children and adolescents.

Impact on physical health

ARFID can have serious physical health consequences, including weight loss, malnutrition, dehydration, electrolyte imbalances, and gastrointestinal problems.

Psychological factors

Individuals with ARFID may experience anxiety, distress, or impairment related to their eating patterns. They may also have comorbid mental health conditions such as anxiety disorders, obsessive-compulsive disorder (OCD), or autism spectrum disorder.

Onset and course

ARFID can develop at any stage through childhood to adolescence and adulthood. In children, it may be associated with feeding difficulties in early years, while in adults it may develop in response to trauma, medical conditions, or psychological factors.

Orthorexia

*Not yet formally recognised as an eating disorder.

Although not formally categorised and recognised as an eating disorder in diagnostic manuals, orthorexia involves an obsessive focus on eating only foods perceived as healthy. This often leads to restrictive eating patterns with negative consequences for physical and mental health.

Eating disorders can have serious long-term as well as short-term physical health consequences, including malnutrition, electrolyte imbalances, gastrointestinal problems, cardiovascular issues, and bone density loss. They also have significant psychological effects, such as depression, anxiety, low self-esteem, and social isolation. Without proper treatment, eating disorders can be life-threatening.