Many patients suffering from GERD or acid reflux are on acid blocking medications. When I tell them their symptoms aren’t necessarily due to overproduction of acid, they look surprised. I tell them Acid blockers help with the symptoms, but in most cases, it doesn’t address the underlying issue. This article will shed some light on the most common causes of GERD or acid reflux.
The Claim: Acid Reflux (GERD) Is Always Due to Excessive Stomach Acid?
As you will see, Acid Reflux is Absolutely Not always due to excessive stomach acid.
What Is Acid Reflux
Acid Reflux is a phenomenon whereby acid (and sometimes other substances) come upwards, from the stomach back into the esophagus/throat.
Since the symptoms revolve around acid, and long term consequences of acid in the esophagus are quite serious, acid blockers are often prescribed.
The Usual Culprit: Lower Esophageal Sphincter Dysfunction
The Lower Esophageal Sphincter (LES) is what separates the esophagus from the stomach. When it’s open it lets food go into the stomach. If it’s closed, it keeps things that should be in the stomach out of the esophagus. At rest, the sphincter tends to be open. Swallowing will stimulate the nervous system to hold the sphincter closed.
One of the most common causes of Acid Reflux or GERD is LES weakening  or failure to close altogether .
A number of factors are associated with a weak lower esophageal spincter, including:
- Factors that can weaken the sphincter
- Pressure gradients – if pressure through sphincter is weaker than abdominal or gastric pressure – it will open
- Dietary Fat intake
- Eating (due to effects of hormones secretin and cholecystokinin)
- Colonic fermentation (we don’t know why or how)
- Pregnancy (progesterone)
- Medications: Anticholinergic drugs, Nitrates, Calcium channel blockers, prostaglandins (pain meds)
We often experience Transient Relaxation of the LES; meaning the weakness doesn’t persist, its only there for 5-30 seconds , which explains why some diagnostic imaging may miss LES dysfunction.
Sometimes Acid Reflux is Due to Too much Acid, but these are special circumstances
There are a few conditions whereby our bodies secrete Gastrin (which stimulates more acid production). These conditions are relatively uncommon; most people with acid suppression medications do not have these conditions.
Gastrin Releasing Tumors
A particular type of tumor called gastrinomas have potential for excessive acid production. They are quite uncommon, only 3% of the population has these . A condition called Zollinger-Ellison Syndrome is the most common type, representing 30%  of that tiny 3%.
After Prolonged Use of Acid Blockers
When we have low stomach acid, our stomachs will make more gastrin; gastrin is a signal which looks to make more acid. The gastrin will get to its highest point (15% higher than it is supposed to be) by about the 4th month of treatment . Once a person stops the Acid blocker, we experience a transient over secretion of acid early on. Luckily, this tends to only last for about 7 days or so .
Infection with H. Pylori initially causes damage to the acid producing cells (causing decreased acid production) which in turn creates more gastrin. Upon irradiation of the bacteria, hypergastrinemia may result in over secretion of acid .
Is Reflux Always from Too Much Acid?
Nope. We find most cases are due to anatomical dysfunction rather than too much acid being produced. Investigating why the symptoms exist may be helpful in weighting all the options in treatment.