Acid reflux is when acid from the stomach leaks or backwashes (refluxes) up into the gullet (esophagus). This may cause heartburn and other symptoms. The condition is called GERD (Gastroesophageal Reflux Disease).
When we eat, food passes down the esophagus into the stomach. Cells in the lining of the stomach make acid and other chemicals which help to digest food. Stomach cells also make mucus which protects them from damage from the acid. The cells lining the esophagus are different and have little protection from acid.
There is a circular band of muscle (a 'sphincter') at the junction between the esophagus and stomach. This relaxes to allow food down, but then normally tightens up and stops food and acid leaking back up (refluxing) into the esophagus. In effect, the sphincter acts like a valve.
Acid reflux is when some acid leaks up (refluxes) into the esophagus. Esophagitis means inflammation of the lining of the esophagus. Most cases of esophagitis are due to reflux of stomach acid which irritates the inside lining of the esophagus.
The lining of the esophagus can cope with a certain amount of acid. However, it is more sensitive to acid in some people. Therefore, some people develop symptoms with only a small amount of reflux. However, some people have a lot of reflux without developing esophagitis or symptoms.
By Mortin - Copyright 2009
Last modification 31/12/2009
What is Acid Reflux?- References