No single cause of eating disorders has been found to date. There are a variety of influences with eating disorders, including personality and genetics, as well as biochemical, socio-cultural, familial, and experiential factors. Each individual is different, and no two stories are the same. It is important to be educated about eating disorders and find the type of treatment that works best for each person.
There are a variety of types of eating disorders: Anorexia, Bulimia, Binge Eating Disorder, Other Specified Feeding or Eating Disorder (OSFED), and Avoidant/Restrictive Food Intake Disorder (ARFID).
Anorexia 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, by:
- Persistent behaviours that interfere with maintaining an adequate weight for health. Typically, these behaviours 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 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; therefore failing to gain weight or grow is just as concerning as weight loss;
- 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 – behaviour 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;
- Disturbance in how the person experiences their weight and shape. The person overestimates their body size, usually evaluates it negatively, and feels their weight and shape matter more than most anything else about them; and
- The person does not fully appreciate the seriousness of their condition. Anorexia is linked with cardiac arrest, suicidality, and other causes of death.
Anorexia was previously associated with the loss of menstrual periods which made it difficult or impossible to identify in males or in pre-pubescent children or teens – this aspect is no longer necessary for diagnosis.
Other symptoms may include:
- Depressed mood
- Anxiety (especially social anxiety)
- Obsessive-compulsive disorder
- Social withdrawal
- Irritability, insomnia, and intense preoccupation with food, all of which can be directly related to insufficient nutrition
- Feelings of inefficacy
- Rigid, all-or-nothing thinking
- Strong desire for control
While the causes of anorexia nervosa are not completely understood by medical and psychological professionals, it is acknowledged that an array of biological, social, genetic, and psychological factors play a role in increasing the risk of its onset.
Bulimia Nervosa is a life threatening mental illness characterized by:
- Recurring episodes of food restriction followed by binge eating. A binge-eating episode is characterized by:
a) The consumption of an unusually large amount of food within a relatively short period of time.
b) Feeling out of control over what and how much is eaten.
- Recurring behaviours that follow bingeing, which are meant to “purge” the body of food and prevent weight gain. These behaviours can include excessive exercise, fasting or severe restriction, self-induced vomiting, and misuse of laxatives, diuretics, or enemas. Note: Vomiting can cause severe dehydration and damage to the esophagus and mouth. Dehydration can also be caused by the misuse of laxatives and diuretics and excessive exercise. These types of purging can lead to imbalances in essential body minerals and salts, which can cause cardiac arrest and/or stroke. In addition, they do not get rid of most of the calories eaten during a binge.
- The person tends to negatively evaluate their weight and shape and feels these matter more than most anything else about them; and
- The restricting, bingeing, and purging cycle occurs at least once a week for three months. Individuals with bulimia often experience shame or embarrassment about their bingeing and purging and may go to extreme lengths to hide these behaviours. They often fall within a “normal” weight range, though there may be frequent fluctuations, making it difficult for loved ones to recognize the eating disorder. Bulimia is commonly linked with depression and may also be linked with self-harm and suicidality.
Binge Eating Disorder
Binge-eating disorder is characterized by recurring episodes of binge eating. It is important to note that overeating and binge-eating are not the same. Overeating can be described as consuming more food than your body needs at a given time. When a person overeats, it may be simply because the food is available and is very appetizing. An example of overeating may be eating a second serving of dessert after a full meal. Most people overeat on occasion. Binge-eating is much less common and is marked by psychological distress.
- A binge-eating episode is characterized by:
a) The consumption of an unusually large amount of food during a relatively short period of time.
b) Feeling out of control over what and how much is eaten and when to stop
- A binge-eating episode also includes three or more of the following:
a) Eating very quickly
b) Eating regardless of hunger cues, even if one is already full
c) Eating until uncomfortably or painfully full
d) Eating alone due to embarrassment about the type and quantity of food ingested
e) Feelings of self-disgust, guilt, and depression
- The binge-eating episodes are not followed by compensating behaviours, such as in bulimia (excessive exercise, self-induced vomiting, or the misuse of laxatives or diuretics).
- Binge-eating is seen as a disorder when the bingeing episodes occur at least once a week for three months or more.
Other Specified Feeding or Eating Disorder (OSFED)
The eating disorders in this category are related to anorexia nervosa, bulimia nervosa, and binge-eating disorder but differ in that not all of the same conditions apply.
- Atypical anorexia nervosa: all of 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,
- Bulimia nervosa (of low frequency and/or limited duration): all of the same characteristics as for bulimia nervosa, however the cycle of bingeing and purging occurs less frequently than once per week and/or for fewer than three months.
- Binge-eating disorder (of low frequency and/or limited duration): all of the same characteristics as for binge-eating disorder; however the binge-eating episodes occur less frequently than once per week and/or for fewer than three months.
- Purging disorder: Persistent purging behaviours without the presence of binge-eating episodes.
- Night eating syndrome: The excessive consumption of food following an evening meal or after waking from sleep in the night, which causes extreme psychological distress and interferes with daily functioning.
Avoidant/Restrictive Food Intake Disorder
Symptoms of this eating disorder typically show up in infancy or childhood. A child may avoid foods with certain textures or colours, or a traumatic experience involving food, such as becoming physically ill after food consumption, may result in a fear of eating.
ARFID does not include experiences of body dissatisfaction or disturbances in the way body weight or shape are perceived. However, if left untreated, it can develop into anorexia nervosa or bulimia nervosa later in adolescence or adulthood.
Through this eating disorder, the body’s requirements for nutrition and energy are consistently not being met. This manifests in one or more of the following:
- Significant weight loss (or not achieving expected weight gain in children), or
- Significant nutritional deficiency leading to suboptimal development, or
- Dependence on nutritional supplements, or
- Marked interference with psychosocial, and potentially physical, functioning
Note: a diagnosis of ARFID requires that the inadequate food intake is not better explained by limited access to food or by a medical condition.
All information taken from the National Eating Disorder Information Centre website © 2014