Bulimia Nervosa Harm Mechanisms

The intuition that bulimia is dangerous mostly because of stomach acid damage misses the actual killer. The leading cause of death in bulimia nervosa is hypokalemia-induced cardiac arrhythmia — repeated vomiting drives metabolic alkalosis, the kidney dumps potassium in response, and low serum potassium prolongs the QT interval and can trigger torsades de pointes or ventricular fibrillation. Crude mortality is roughly 3.9% with an SMR around 2, and about a quarter of inpatient cases show hypokalemia. The full harm profile includes at least seven distinct pathways: 1. Electrolyte derangement — the actual mortality driver via cardiac sudden death. 2. Esophageal injuries — Mallory-Weiss tears (mucosal tears at the gastro-esophageal junction), the rare but catastrophic Boerhaave syndrome (full-thickness rupture, 35-90% mortality depending on time to surgery), Barrett's esophagus from chronic reflux, strictures, and GERD. 3. Dental erosion on the lingual surfaces of upper teeth — the signature pattern dentists recognize — plus parotid gland hypertrophy ("chipmunk cheeks") and increased caries. 4. Hypokalemic nephropathy — chronic kidney damage from sustained low potassium. 5. Cardiac changes beyond arrhythmia, including cardiomyopathy from chronic malnutrition. 6. GI motility problems: gastroparesis, laxative dependence, paradoxical micronutrient deficiency despite eating. 7. Hormonal and skeletal: amenorrhea, osteoporosis (often permanent if not corrected early), and Russell's sign (knuckle calluses from self-induced vomiting). Overlaying all of it: extremely high comorbidity with depression, anxiety, OCD, and substance use, plus elevated suicide risk. Proton pump inhibitors like omeprazole are used clinically as damage-reduction for the reflux and esophagitis components, but they do not prevent electrolyte loss, mechanical tears, or the psychiatric compulsion. The only FDA-approved pharmacotherapy specifically for bulimia nervosa is fluoxetine, which targets the binge-purge drive rather than GI consequences; gold-standard treatment is CBT-E plus nutritional rehabilitation. This is informational, not medical advice. People experiencing eating-disorder symptoms should consult clinicians.