Obesity is associated with gastroesophageal reflux disease (GERD), and there is a linear association between GERD symptoms and body mass index. Factors that may play a role are pressure or behavior of the lower esophageal sphincter and impaired esophageal peristalsis, with decrease esophageal clearance. In addition, alteration of the angle of His and an increase of the trans-diaphragmatic pressure gradient play an important role. Today the bariatric procedures most popular for the treatment of morbid obesity are sleeve gastrectomy and the Roux-en-Y gastric bypass. While very effective in determining weight loss with improvement of comorbidities, in some patients these procedures can worsen preexisting reflux, or even cause de novo reflux.