What is heartburn?
Heartburn is a burning discomfort that is generally felt in the chest just behind the breastbone. The burning sensation results when harsh stomach juices come in contact with and irritate the delicate lining of the esophagus, the tube-like structure that connects the mouth to the stomach.
Why do stomach juices irritate the esophagus?
These juices, which are produced by the stomach to help the body break down food, contain a powerful acid called hydrochloric acid. While the stomach is naturally protected from this potent acid, the esophagus does not share the same protective qualities as the stomach. So, if acidic stomach contents come into contact with the esophagus, its skin-like lining can be irritated or injured and result in the sensation known as heartburn.
What causes heartburn?
Heartburn is caused when acidic stomach juices reflux — or flow backward — into the esophagus. This generally occurs when the lower esophageal sphincter (LES) — the natural valve that keeps stomach acid in the stomach and out of the esophagus — relaxes or is not functioning properly.
When functioning normally, the LES opens like a door that allows food into the stomach but not out the same way. However, at times the LES relaxes and allows stomach juices to flow upward into the esophagus. This relaxation exposes the esophagus to the harsh acid from the stomach. Physicians refer to this as gastroesophageal reflux.
