What causes gastro-oesophageal reflux and disease?
When a person has reflux the contents of the stomach and stomach acid regurgitates, or back-washes from the stomach back up into the esophagus. Normally there is a barrier called the lower esophageal sphincter (LES) which is a lower muscle of the esophagus . The majority of the time it is contracted (or tight), closing off the esophagus from the stomach, helping to stop the back flow of stomach acid and contents. In people with reflux the LES does not function normally. It could be either immature (infants), weak or have a tendency to relax inappropriately.
