As a further possible eating disorder (with some proximity to obsessive-compulsive disorders), we must also now include orthorexia (prevalence figures still very vague; probably also 1–3% of the general population).
Anorexia is characterised by intentionally induced weight loss (through avoidance of high-calorie foods, excessive physical activity or other measures such as self-induced vomiting, use of laxatives, appetite suppressants or diuretics), persistently low body weight (at least 15% below expected weight or BMI below 17.5), the presence of a body image disturbance, the constant fear and simultaneous rigid conviction of being too fat, and ultimately hormonal consequences including amenorrhoea in women and loss of potency in men. Anorexia is associated with a high degree of denial. In clinical practice, alongside the restrictive, "ascetic" form of anorexia, we also see bulimic forms with periodic binge-purge cycles. Common somatic consequences include, in addition to the often increasingly threatening underweight and the aforementioned hormonal disturbances (due to oestrogen deficiency and cortisol elevation), thyroid dysfunction, the development of osteoporosis, renal insufficiency, electrolyte imbalances and cardiac arrhythmias. The mortality rate from the direct consequences of anorexia is 15%. Bulimia is similarly characterised by a persistent preoccupation with food, but here with an irresistible craving for food and subsequent binge-eating episodes with loss of control and intake of large quantities of high-calorie foods. The "fattening" effect of these episodes is counteracted by measures such as self-induced vomiting, misuse of laxatives, appetite suppressants and periods of fasting. A morbid fear of becoming fat is also present in bulimia. Bulimia is frequently preceded by anorexia. Typical somatic consequences of bulimia include dental enamel damage, oesophageal and gastric mucosa inflammation, swelling of the parotid glands, electrolyte imbalances, cardiac arrhythmias and renal insufficiency.
Binge eating disorder is defined as an eating disorder in which binge-eating episodes occur as a possible response to psychological distress, ultimately leading to obesity. It thus also involves eating episodes for the purpose of emotion regulation, with experienced loss of control, followed by feelings of disgust and shame, but without counterregulatory measures.
Orthorexia is the term we use for a syndrome characterised by a compulsive focus on (supposedly) healthy eating and exaggerated concern about which foods may be unhealthy and which must be avoided, followed by restrictive eating behaviour and avoidant dietary rules, ultimately resulting in malnutrition and/or nutritional deficiency.
