Gastroesophageal reflux disease (GERD) and obesity coexist in many patients. The association is not coincidental, since obesity plays a major role in the pathophysiology of GERD. Obesity is associated with a higher number of transient lower esophageal sphincter relaxations and abnormal peristalsis. Central obesity increases the trans-diaphragmatic pressure gradient and disrupts the anatomy of the gastroesophageal junction by causing hiatal hernia formation. Sleeve gastrectomy influences GERD pathophysiology.