Cause of GERD

A thick layer of muscle is present at the lower end of the food pipe (esophagus) and it acts like a valve. This is called the lower esophageal sphincter. 

When we swallow it allows food and liquid to flow into the stomach and prevents backflow. 

If the sphincter relaxes abnormally or weakens, stomach acid can flow back up into your esophagus.

The cause of GERD is multifactorial. A number of risk factors (discussed subsequently) can affect the disease process.

Increased sensitivity in the inner lining of the esophagus (known as hypersensitive esophagus) can also lead to severe symptoms even with minimal or no acid exposure (discussed later).