The DSM-IV, the diagnostic manual for psychology professionals, defines anorexia nervosa as:
a) Recurrent episodes of binge eating. An episode of binge
eating is characterised by both of the following:
1) eating, in a discrete period of time (e.g. within any 2-hour period), an
amount of food that is infinitely larger than most people would eat during a
similar period of time and under similar circumstances
2) a sense of lack of control over eating during the episode (e.g., a feeling
that one cannot stop eating or control what or how one is eating)
b) Recurrent inappropriate compensatory behaviour in order to prevent weight
gain, such as self-induced vomiting; mis-use of laxatives, diuretics, enemas, or
other medications; fasting; or excessive exercise
c) The binge and inappropriate compensatory behaviours both occur, on average,
at least twice a week for 3 months
d) Self-evaluation is unduly influenced by body shape and weight
e) The disturbance does not occur exclusively during episodes of Anorexia
Nervosa
It further specifies two types of the disease - purging type and non-purging type.
Purging: during the current episode of BN, the person has
regularly engaged in self-induced vomiting or the mis-use of laxatives,
diuretics or enemas
Non purging: during the current episode of BN, the person has used other
compensatory behaviours, such as fasting or excessive exercise, but has not
regularly engaged in self-induced vomiting or the mis-use of laxatives,
diuretics or enemas
As with anorexia nervosa, the usefulness of these criteria is rather limited beyond that of aiding in the recognition of the illness by medical professionals. Here, too, they are of little use in explaining the nature of the disease and how it affects those who suffer from it.
Low self-esteem is widely recognised as a point of commonality not only amongst bulimics, but among all those afflicted by eating disorders. This diminished sense of self-worth, combined with psychological, emotional, physical and even social issues which the individual finds themselves unable or unwilling to face, can lead to the development of dysfunctional coping mechanisms. Bulimia nervosa is one example of this.
Bulimics seek to block out or numb themselves to the serious issues which underlie their illness by feasting on large quantities of food, often consuming in a single sitting more than the recommended intake for an entire day. They are then overcome by an uncontrollable urge, some describing it as a panic, to rid themselves of the food they've consumed. This is done either by induced vomiting, mis-use of laxatives and enemas or compulsive exercising as a way of compensating for the over-indulgence.
Bulimia often goes undetected due to the fact that many who suffer from it remain within the expected weight range for their age, height and frame. In fact, a certain percentage of bulimics are known to be overweight. As a result, it may go undetected until the individual experiences life-threatening complications from the illness.
The physical effects of bulimia include dehydration, erosion of tooth enamel, electrolyte imbalances, cardiac arrhythmias and damage to the oesophagus potentially leading to rupture, haemorrhage and even death.
Like anorexia, bulimia nervosa is most prevalent in Caucasian women who come from middle to upper-class backgrounds. It's prevalence amongst males and non-whites is also on the rise. It, too, is almost exclusively seen in heavily industrialised countries.