Obesity has increased dramatically in the last 30 years, affecting 33% of the adult population in the United States. Increase in body mass index has been shown to be associated with the increase in the prevalence of gastroesophageal reflux disease (GERD) symptoms, esophageal mucosal injury, and GERD complications. The putative mechanisms responsible for the close relationship between GERD and increased body mass index include increased intragastric pressure, increased gastroesophageal pressure gradient, esophageal motor and sensory abnormalities, increase in prevalence of hiatal hernia, increase in serum female hormonal levels, diet, and increase in comorbidities. Whilst the current efforts are to focus on one major underlying mechanism, it is highly likely that multiple factors contribute to the increased prevalence of GERD in the obese patient.