Heartburn Overview

Causes

Almost everyone has occasional heartburn. If you have frequent, ongoing heartburn, you may have gastroesophageal reflux disease (GERD).

Normally, when food or liquid enters your stomach, a band of muscle at the end of your esophagus (called the lower esophageal sphincter or LES) closes off the esophagus. If this muscle fails to close tightly enough, stomach contents can back up (reflux) into the esophagus. This partially digested material is usually acidic and can irritate the esophagus, causing heartburn and other symptoms.

Heartburn is more likely to occur if you have a hiatal hernia , which is when the top part of the stomach protrudes upward into the chest cavity. This weakens the LES and makes it easier for acid to reflux from the stomach into the esophagus.

Heartburn can be brought on or worsened by pregnancy ...