Gastroesophageal reflux disease (GERD) is a common occurrence when a ring-like muscle located at the bottom of the esophagus (the tube that carries food from your mouth to your stomach) opens for varying periods of time, or does not close properly and stomach contents come up into the esophagus. GERD is also called acid reflux or heartburn, because digestive juices—called acids—come up with the food. The esophagus is the tube that carries food from the mouth to the stomach.

When acid reflux occurs, food or fluid can be tasted in the back of the mouth. When refluxed stomach acid touches the lining of the esophagus it may cause a burning sensation in the chest or throat called heartburn or acid indigestion. Occasional heartburn is common and does not necessarily mean one has GERD. Persistent reflux that occurs more than twice a week is considered GERD, and it can eventually lead to more serious health problems. People of all ages can have GERD.