National Eating Disorders Awareness: What are Eating Disorders?

From February 23 through March 1, the National Eating Disorders Association is hosting it's annual awareness week to promote knowledge and understanding of eating disorders. The charity reports that last year all U.S. states plus 51 international countries took part in raising awareness through events. The theme of this year is simply named "I Had No Idea" and aims to help society overcome misconceptions about eating disorders through raising awareness. As it is not only the social implications of eating disorders which are misunderstood, this article aims to briefly explain the medical aspects of a few both common and uncommon eating disorders.

Please note that most of this information comes from the latest edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V). Whilst it is considered to be "the bible of psychiatry", some professionals do not think it is completely flawless and accurate. This list is not exhaustive and many additional eating disorders are thought to exist.

Types of Eating Disorders

Anorexia Nervosa

Anorexia is possibly the most well-known eating disorder. This may be due to the fact that it is the most portrayed in the media through both fictional characters and affected celebrities. Anorexia is estimated to affect up to 1% of American women. Over 90% of sufferers are thought to be female. The DSM-V diagnostic criteria for anorexia is:

  • restriction of food intake to an amount which is considered too low based on that expected of the sex, gender, age and level of physical activity of the sufferer, leading to a low body weight. In the DSM-IV, the body weight criteria for anorexia was that an individual weighs less than 85% of their ideal body weight. This technical requirement has been traded for the less confining "significantly low body weight".
  • an intense fear of weight gain in spite of low body weight and unlikelihood of gaining weight. The sufferer's thoughts are preoccupied with food and weight.
  • inability to recognize the fact that they are at a low weight and engaging in unhealthy behaviors. The sufferer usually has a poor body image and general lack of confidence.

There are two subtypes of anorexia. The binge eating / purging subtype requires the all of the above criteria to be met, plus that the individual often binges (consumes large amounts of food in short periods of time) and purges for a duration of at least three months. Purging is an attempt to discard calories through voluntarily vomiting or abusing laxatives, diuretics and enemas. The restricting subtype requires all of the above criteria to be met and that the individual does not binge or purge.

The potential complications of anorexia are severe. It is estimated that up to one fifth of sufferers will die of their eating disorder, giving it the highest mortality rate of all mental illnesses. Sufferers may die due to the physical side effects, such as malnourishment or a heart attack, or the psychological side effects, such as depression leading to suicide. Those who don't die potentially face physical complications such as heart problems, osteoporosis (weakening of the bones which only affects women) and infertility.

Bulimia Nervosa

Alongside anorexia, this is another commonly known eating disorder. It is thought to affect up to 2% of women, who are estimated to represent 80% of sufferers. The DSM-V diagnostic criteria for bulimia is:

  • regular consumption of an excessive amount of food in a short period of time (known as 'bingeing'), in situations where eating that amount of food would not be considered normal.
  • During these binges, the individual feels like they cannot control their eating or that they cannot stop.
  • The individual regularly goes to extreme lengths to compensate for binges. Their methods differ depending on their subtype. The purging subtype means an individual often voluntarily vomits or abuses laxatives, diuretics and enemas. The non-purging subtype is not accurately named; the individual still often compensates for binges except in manners which may be considered less destructive, for example through excessive exercise.
  • They should engage in these behaviors once a week or more for three months.
  • Similarly to anorexia, the individual's mind is preoccupied with thoughts of food and weight.
  • Again, like anorexia, bulimia is associated with a poor body image and low confidence. Suffers may not realize or understand the seriousness of their illness.
  • The sufferer cannot be diagnosed with bulimia if they have recently been diagnosed with anorexia.

The nature of bulimia means that sufferers are less likely to be underweight than people with anorexia. Many bulimics do become underweight and suffer from weight-related health consequences. However, bulimia can have devastating medical side effects regardless of weight. In severe cases, self-induced vomiting can lead to heart failure and epilepsy. Complications also include tooth decay, irregular bowel movements and an irregular heartbeat. Non-purging bulimia can also lead to heart problems. Both subtypes are associated with other mental illnesses.

Eating Disorder Not Otherwise Specified (EDNOS) or Other Specified Feeding or Eating Disorder (OSFED).

This disorder has two names, the former being used in the DSM-IV and the latter in the DSM-V. The acronym 'EDNOS' will be used here as it is still the most commonly used term. EDNOS is a self explanatory eating disorder - it is used as a 'catch-all' diagnosis for individuals who meet most, but not all, criteria for other eating disorders. This diagnosis has been praised for allowing individuals with uncommon eating disorders to get help rather than having to suffer until they potentially worsen enough to be diagnosed with another eating disorder. However, the use of the EDNOS diagnosis has also been criticized for allowing different eating disorders to be lumped together, resulting in poor treatment. Another common complaint about EDNOS is the claim that it is not taken as seriously as other eating disorders. The DSM-V advises mental health professionals to use this diagnosis less, especially as changes to the diagnostic criteria for other eating disorders remove factors which may have excluded individuals from a different diagnosis.

EDNOS is more of an amalgamation of eating disorders rather than a specific eating disorder. As such, the criteria is based on a lack of criteria met for other eating disorders, such as:

  • All criteria for anorexia is met except for a low body weight. EDNOS is usually diagnosed even if the individual has lost a large amount of weight through anorexic behaviors. This is known as atypical anorexia nervosa.
  • All criteria for bulimia is met except the individual does not binge and purge often enough, or they have been doing so for less than three months.
  • All criteria for Binge Eating Disorder is met except the individual does not binge often enough, or has been doing so for less than three months.

These are common reasons why EDNOS is diagnosed but the full list is extensive. The diagnosis can be made due to the absence of any criteria for another eating disorder. The complications of EDNOS are wide-ranging, but some research suggests that it has a higher mortality rate than anorexia. Other complications tend to be similar to whichever other eating disorder the sufferer's condition is similar to.

Binge Eating Disorder (BED)

This eating disorder was recognized in the recently published DSM-V after being added to the appendix of the DSM-IV as a "diagnosis for further study". Despite it's new status as an officially recognized disorder, BED is thought to be the most common eating disorder, estimated to affect up to 5% of Americans alone. This is more than the estimated sufferers of anorexia and bulimia combined. As eating disorders are usually associated with a restrictive intake, many sufferers of BED are thought to be unaware of their eating disorder.

  • Similarly to bulimia, BED requires an individual to regularly consume an excessive amount of food in a short period of time ('bingeing') and that they feel out of control during this.
  • The individual should also meet at least three of the following criteria: eating very fast; eating until they are too full; bingeing even when they are not hungry; choosing to eat alone because of shame; experiencing negative feeling relating to their eating habits. These factors indicate that the sufferer's eating habits are uncontrollable and they know this.
  • The individual feels very unhappy due to their eating habits.
  • They engage in this behavior once a week or more for a duration of three months.
  • They do not compensate for their binges, nor do they also suffer from anorexia or bulimia.

Although some BED sufferers are of a healthy weight, the weight gain associated with bingeing does mean most are overweight or obese. Therefore, most potential health problems are related to weight. Particular risks include high blood pressure and cholesterol, heart disease and type 2 diabetes. From a medical point of view, BED is considered less harmful in the short term than eating disorders associated with weight loss. In the long term, however, BED can cause life-threatening medical conditions if left untreated. Like all other eating disorders, it is not uncommon for sufferers to have another mental health problem, particularly depression. These can be exacerbated by BED, or vice versa.

Currently unrecognized Eating Disorders

Similarly to how BED wasn't until 2013, not all suspected types of eating disorders are currently recognized by the DSM. These include:


Diabulimia is a suspected eating disorder which affects people suffering from type 1 diabetes. These diabetics have to use insulin to control their illness, which can have the unwanted side effect of weight gain. Diabulimia refers to diabetics who intentionally lower their intake of insulin in an attempt to lose weight. The term is controversial because there is currently no officially recognized eating disorder with such a direct link to a physical health problem. There is also discussion as to whether diabulimia is a subtype of another eating disorder rather than a separate one. This proposed eating disorder is very dangerous as it has the same consequences as poorly managed diabetes. At the worst it can cause strokes, comas and death.


Orthorexia nervosa is a suspected eating disorder defined in 1997 by Steven Bratman, a medical doctor who believed he was suffering from it. The idea that this is an eating disorder is controversial as sufferers display behavior which is very different from other eating disorders - they intend to lead a healthy lifestyle. Whilst this does not sound disordered in theory, orthorexia refers to the obsessive need to eat healthily. Sufferers may cut out entire food groups from their diet on the basis that these foods are 'unhealthy' even if they are not generally considered so. Such food groups may include meat and animal products, processed foods, sugar, artificial flavors and preservatives, gluten and refined carbohydrates. Orthorexics' obsession with food can ironically lead to malnutrition and weight loss, alongside potentially being linked to mental health issues such as anxiety. As orthorexics are very restrictive in their diet, they may be at risk of developing anorexia.

Getting Help

If you are concerned that you or someone you know is suffering from an eating disorder and want to seek help, a good first step would be to contact a charity such as the National Eating Disorders Association in the USA or Beat in the UK. These charities can provide practical advice about how to overcome an eating disorder as well as psychological support. If possible, it is also a good idea to visit a doctor - charities will be able to advise you on any available financial support if this is a concern. Whilst only a trained professional can diagnose an eating disorder, if you or someone you know identifies with one it is never too early (or late) to ask for help.

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