Bulimia nervosa is characterised by a cycle of binge eating and purging behaviours. Binge eating involves a discrete time period where a person feels a loss of control over their eating, as they consume more or different food than usual, and do not feel able to stop eating or limit their intake [10, 11, 1408]. Bingeing is often followed by compensatory behaviours designed to prevent weight gain (e.g., vomiting, use of laxatives, fasting or excessive exercising). As with anorexia nervosa, a person’s perception of their value and self-worth is disproportionately influenced by their body weight, size, and shape [10].
The cycle of bingeing and purging is maintained by the belief that control over one’s eating, weight, and shape will increase a person’s self-worth, and that by restricting and compensating after a binge they are effectively managing weight. However, restricting food intake leads to binge eating which then results in compensatory behaviours [1414]. Negative mood states such as sadness, frustration, anger, fear, or loneliness, can exacerbate this cycle [1418, 1419].
As described in Chapter A4, people with bulimia nervosa may present with symptoms of extreme dietary restrictions and/or exercise plans without purging behaviours [1408]. Further, people with bulimia nervosa are often ashamed of their eating behaviours, and attempt to hide or conceal their symptoms [428, 1420]. Some people even report deliberately selecting certain compensatory behaviours, such as vaping, because they are easy to conceal [1421]. As such, bulimia nervosa can be an isolating disorder [1414]. As with anorexia nervosa, the outward symptoms can be difficult to observe, particularly as people with bulimia nervosa may not display the same dramatic loss in weight. Physical signs a person may present with may include [1410, 1414, 1422]:
- Fatigue.
- Bloating and constipation.
- Gastric acid reflux, which can lead to difficulty swallowing or indigestion.
- Abdominal pain and distension.
- Calloused knuckles.
- Hoarse voice.
- Delayed digestion.
- Electrolyte abnormalities, such as hypokalaemia (low potassium).
- Muscle spasms.
- Heart palpitations.
- Nausea.
- Poor kidney function.
- Dental erosion.
- Enlarged glands.
- Poor colon function.