Bulimia and binge eating disorders are serious psychiatric illnesses.
Eating disorders in general are characterised by the over valuation of shape and weight, an over investment in controlling weight and shape, and severe disturbances in eating.
When people think of eating disorders and what a person with an eating disorder might look like, they often think of anorexia – being severely underweight. However, for conditions such as bulimia nervosa and binge eating disorders, the weight of the individual does not determine a diagnosis.
With both of these conditions, a person can be of any weight – but are usually in the healthy weight range, and sometimes even in the overweight and obese range, particularly for those with binge eating disorders.
Bulimia and binge eating disorders both include recurrent episodes of binge eating, which involves eating in a period of time (normally around 2 hours) an amount of food that is definitely larger than what most people would eat during a similar period, and a sense of lack of control over eating during the episode.
In both conditions, the binge eating behaviour must occur on average at least once a week for 3 months to meet the criteria for a diagnosis. Despite the similarities, there are still significant differences between the two conditions.
In addition to the recurrent binge eating episodes, individuals with bulimia also engage in compensatory behaviours which are used to prevent weight gain following a binge. This may involve self-induced vomiting which is most common, misuse of laxatives or diuretics, fasting, or excessive exercise.
Finally, as with all eating disorders, the behaviour is triggered by self-evaluation that is influenced by body weight and shape.
Binge Eating Disorder
The main difference between binge eating disorder and bulimia is the absence of compensatory behaviours in binge eating disorder. The diagnosis also puts more emphasis on what is occurring during the binge.
In this condition, the binge eating episode is associated with eating more rapidly than normal, eating until feeling uncomfortably full, eating large amounts of food when not physically hungry, eating alone due to embarrassment over the amount of food, feeling disgusted, depressed or guilty afterwards and being markedly distressed.
How do Bulimia and Binge Eating Disorders differ from Anorexia?
On the surface, anorexia is characterised by severe energy restriction and individuals with anorexia are commonly underweight.
Binge eating disorder and bulimia on the other hard are characterised by periods of bingeing which means that people can be overweight.
The other main difference is that people with anorexia suffer from a distorted view of their own body which is not experienced by individuals who are diagnosed with bulimia or binge eating disorder. People with bulimia, and even binge eating disorder, are concerned about their body shape and weight but do not have the distorted view that is present in anorexia.
It is important to note however, that not everyone fits perfectly into these diagnoses as some people may exhibit characteristics from more than one eating disorder – for example in anorexia there is a binge/purging subtype that exhibits characteristics of both anorexia and bulimia.
There is also a diagnosis called Other Specified Feeding or Eating Disorder (OSFED) which refers to conditions that don’t fit the standard diagnosis, but the eating behaviours are causing clinically significant distress.
The Energy Balance of Binge Eating
A binge generally lasts for around 2 hours and during this time a person will eat a significant amount of food to the point of being uncomfortably full.
During a binge, a person can consume anywhere from approximately 1500 to 3500 calories, which for a teenage girl, can represent from 75% to 175% of daily requirements.
For individuals with a binge eating disorder, this means that their energy balance is shifted largely in the direction of weight gain.
For individuals with bulimia, purging occurs following a binge to compensate for the calories consumed.
However as the binge usually lasts for around 2 hours, a significant amount of calories are absorbed before the purge happens. Regardless of the size of the binge, in general around 1200 calories are still absorbed even after purging. This explains why individuals with bulimia are not often underweight.
For more information about bulimia and binge eating disorders, and eating disorders in general, have a look at http://eatingdisordersinfo.org.au, a site that has been developed by the National Eating Disorders Collaboration to help young people with eating disorders.
Author: Ashleigh Hamilton, BHlthSc (Nutr & Diet), MSc (Diet), APD.
Accredited Practicing Dietitian and Nutritionist, Ashleigh Hamilton, is passionate about a whole of body approach to health which encompasses both physical and mental aspects. She works with people to make lifestyle changes that will benefit their health for the future, using a range of counselling techniques including aspects of cognitive behavioural therapy, mindfulness and person-centred therapy.
To make an appointment with Brisbane Dietitian and Nutritionist, Ashleigh Hamilton, try Online Booking – Mt Gravatt or call Vision Psychology (Mt Gravatt) on (07) 3088 5422.
- Kaye, Walter H., et al. “Amount of calories retained after binge eating and vomiting.” American Journal of Psychiatry 150 (1993): 969-969.