When acidic stomach contents flow backward (reflux) from the stomach into the esophagus, people experience the symptoms of gastroesophageal reflux disease or GERD.
Heartburn feels like a burning in the chest below the breastbone, most frequently felt after bending, lying down, or eating. Heartburn is often worse at night and is usually relieved by antacids.
However, not all people suffering from GERD experience heartburn.