What causes gastroesophageal reflux disease (GERD)?
In normal digestion, the lower esophageal sphincter (LES) opens to allow food to pass into the stomach and closes to prevent food and acidic stomach juices from flowing back into the esophagus. Gastroesophageal reflux occurs when the LES is weak or relaxes inappropriately, allowing the stomach’s contents to flow up into the esophagus. The severity of GERD depends on LES dysfunction, as well as the type and amount of fluid brought up from the stomach and the neutralizing effect of saliva.
