Eating Disorders Features
-Distinction was probably too simple originally
-anorexics can also experience periods of binging
-the core of anorexia is
significantly low weight range
Anorexia Nervosa
Extreme fear of gaining weight
Body weight below the normal range (<85%)
Amenorrhea: the absence of a menstrual cycle
May involve such things as: restricted intake, purging (expelling calories through vomiting/diarrhoea) and excessive exercise
Bulimia Nervosa
Binge eating:
o Eating an unusual amount of food in a discrete period of time o Lack of control during episode
o Negative affect after binge
o Pleasure followed by guilt and shame
This is followed by weight compensatory behaviour (could be purging or extreme restriction)
Time frame: at least once per week for 3 months
Self-evaluation influenced by shape (i.e. self-worth based on weight) Binge eating disorder
No (or very little) compensation for the binge eating
Usually put on weight
Time frame: at least once per week for 3 months
Similar feelings of pleasure followed by guilt; but guilt doesn’t result in compensation Prevalence
Relatively infrequent and thus hard to collect data
You need high risk samples covering adolescence and adulthood
Overall prevalence around 2-3% under umbrella of eating disorders- shown by Preti data
Anorexia less common at around 0.5% lifetime
Bulimia is around 1-3% lifetime Sex distribution
Primarily a female disorder
Overall 6-8 times more females
Anorexia most dramatic- 95% of sufferers are females
The way ED’s are defined lean them towards ‘female behaviour’
There could be male equivalents e.g. body builders, runners use drugs, obsessed with muscle gain etc.
Onset
Tend to occur early- disorders of adolescence/early adulthood
Most cases begin during ages 10-20 years (in both BN & AN-show in Preti data)
Anorexia has a mean of 16 years. With almost no cases starting after mid 20’s
Bulimia has a mean of 18 years. First cases appear a little earlier, but a few initial cases seen into middle age (has a longer tail than Anorexia)
BED similar to BN Course
Discrepancy between lifetime and point prevalence- suggests they are temporary disorders
Binge disorders often episodic/short-lived
Anorexia longer- often several years
Long-term data- 75%+ of women no longer have disorder after approximately a decade- but often still show symptoms
Common comorbidity
Mood disorders
o Such overlap with depression that researchers had tried to argue that anorexia was just a variant of depression
