when you swallow food passes down your throat and through your esophagus to your stomach. a muscle called the lower esophageal sphincter controls the opening between the esophagus and the stomach and remains tightly closed except when you swallow food. when this muscle fails to close the acid-containing contents of the stomach can splash back up into the esophagus. this backward movement is called reflux. when stomach acid enters the lower part of the esophagus it can produce a burning sensation commonly referred to as heartburn. gastroesophageal reflux disease (gerd) occurs when reflux is frequent enough to affect your daily life and/or damage your esophagus.
what is gastroesophageal reflux disease?