I am having a pretty good week as far as my acid reflux is concerned. Not had to take any extra medication for about 5 days even on the lower dose medication that I am taking.
The cause of GERD is pretty complex. There are quite a few different causes of acid reflux disease and any number of them can be operating in an individual at various times. But also a person my have all the symptoms but never actually have heartburn.
Some people produce an excess amount of acid but this is actually not the main contributor of GERD. The main problem seems to be the Lower Esophageal sphincter (LES) which is the valve that opens to allow contents into the stomach, but shuts off to prevent the contents returning into the esophagus (normally).
In my own case the LES is not operating properly because I have a hiatus hernia which seems to prevent the valve from closing properly. But other people have different problems with the LES.
The LES is a ring of muscle surrounding the base of the esophagus where it enters the stomach. It is very active most of the time relaxing every time we swallow and then contracting to close off tightly preventing food returning. One of the problems is abnormal relaxations, called transient LES relaxations; they can happen when not swallowing and can last for a lot longer than the normal opening and closing, up to several minutes. This prolonged relaxation allows stomach acid to reflux into the esophagus causing heartburn.
A second problem with the LES is weakening of the muscle where the contractions are weak and are not strong enough to prevent reflux.
One other problem is esophageal contractions. When we swallow the muscles of the esophagus cause a ring like wave starting in the upper esophagus and travel downward to the lower esophagus contracting to push food etc into the stomach.
When this is defective food is not pushed into the stomach in people with GERD and the contractions are also too weak to push acid back into the stomach. This reduces the clearance of acid from the esophagus which is worse at night when trying to sleep.
