Causes and Risk Factors of Acid Reflux (GERD)
GERD commonly develops as a result of failure of the lower oesophageal sphincter or hiatal hernia.
1) Failure of lower oesophageal sphincter
This is the major cause of GERD. Lower oesophageal sphincter (LES) is a ring of muscle between the oesophagus and stomach. When a person swallows, the LES relaxes to allow food and liquid to travel into the stomach, and closes to retain the contents in the stomach for digestion. GERD develops when the LES is weak or relaxed inappropriately, thereby allowing the gastric acid and stomach contents such as food, enzymes and bile to flow backwards into the oesophagus.
Inappropriate relaxation of LES is the cause of acid reflux
2) Hiatal hernia
The oesophagus is a passage that joins the mouth to the stomach, passing through the chest cavity to the abdominal cavity via a hole in the diaphragm known as oesophageal hiatus. Hiatal hernia is a condition where the upper part of the stomach (normally located in the abdominal cavity) pushes or protrudes through the oesophageal hiatus into the chest cavity. This causes gastric acid to flow upwards into the oesophagus, resulting in an inflammation in the lining of the oesophagus and symptoms of GERD to surface.