These classifications come from the DSM-IV, The ‘Diagnostic and Statistical Manual of Mental Disorders’ Fourth Edition, which is published by the American Psychiatric Association. It provides a standard criteria for all known and recognised mental disorders, used in the United States of America and also in varying degrees around the world.
There are three types of eating disorders: Anorexia, Bulimia and ED-NOS (Eating Disorder Not Otherwise Specified). An understanding of Anorexia and ED-NOS is essential in comprehending the sub-types of Bulimia.
The most important thing to remember about Anorexia is that is defined by a weight criterion: “refusal to maintain more than 85% of normal weight.” For adults this equates to a BMI of under 17.5. There are two sub-types of Anorexia: a) Restrictive & b) Binge/Purge type Anorexia.
a) Restrictive Anorexia is the most common type of Anorexia, and is characterised, among other specifications such as the cease of the menstrual cycle (in girls), by a severe restriction of food.
b) Binge/Purge Anorexia also involves an extreme restriction of intake, with inclinations to ‘purge’ food or perceived fat by inducing vomiting, the abuse of laxatives or excessive exercising.
However without fulfilling the weight criterion, a diagnosis of Anorexia is invalid, despite any or all Anorexic behavioral and/or psychological tendencies.
Bulimia is characterised by episodes of binge eating (an uncontrolled consumption of food in a relatively short period of time) followed by an innapproprite ‘compensation’. There are then two sub-types of Bulimia: a) Purging & b) Non-Purging type Bulimia.
a) Purging Bulimia is the most common type of Bulimia, and involves forced vomiting or the abuse of laxatives after binges.
b) Non-Purging Bulimia accounts for 8% of all Bulimia cases. It involves excessive exercising (sometimes called Exercise Bulimia), or periods of extensive fasting after binges. Fasting can last for any number of hours, days, weeks or months.
Note how similar Binge/Purge Anorexia is to Bulimia. The major difference is the weight criterion which excludes non-underweight patients being diagnosed ‘Anorexic’. Many that fear they “eat too much to be Anorexic” are actually unaware they suffer from the equally as dangerous ‘Non-Purging Bulimia’.
ED-NOS is a category for all eating disorders that don’t exactly fit the parameters for either Anorexia or Bulimia, far too broad to address in detail. It can mean any of one number of things:
a) A person who severely restricts food intake but is not yet underweight by DSM-IV standards.
b) A female who meets all other criteria for Anorexia but continues to have regular menstrual periods.
c) A person who regularly binges without engaging in inappropriate compensatory behaviors such as purging (also known as Binge Eating Disorder, see below).
d) Someone who binges and purges but does not meet the frequency or duration requirements for a diagnosis of Bulimia.
e) Someone who regularly purges after eating regular amounts of food, but is not yet “clinically underweight.”
f) Someone who regularly chews food and spits it out without swallowing, but does not meet the criteria for either Bulimia or Anorexia.
g) Any individual who is recovering from or just about to enter one of the ‘specified’ eating disorders.
Binge Eating Disorder (B.E.D.), sometimes referred to as ‘Compulsive Eating’ is practically its own diagnosis in its own right. Proposals are being put forward for the fifth edition of the DSM to this very effect. Note again the similarities between Non-Purging Bulimia and Binge Eating Disorder. The important distinction lies in the purging of Bulimia not present in ED-NOS.
Even though Non-Purging Bulimia and ED-NOS may not get quite as much publicity as its more infamous ‘cousins’, it is important to remember that any eating disorder has the potential to be lethal.
The last edition of the DSM was published in 1994 and is in desperate need of revision in regards to eating disorders, given that over 50% of eating disorders fall into the ED-NOS category. The DSM-5 is due for publication in May 2013.
Please note this was written by a sufferer of Non-Purging Bulimia, rather than a professional doctor.