The Lower Esophageal Sphincter (LES) is what separates the esophagus from the stomach. When it’s open it lets food go into the stomach; when 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.

A number of factors are associated with a weak lower esophageal sphincter, including:

• Pressure gradients – if pressure through the sphincter is weaker than abdominal or gastric pressure – it will open
• Dietary Fat intake
• Eating (due to effects of hormones secretin and cholecystokinin)
• Chocolate
• Alcohol
• Caffeine
• Smoking
• Colonic fermentation (we don’t know why or how)
• Pregnancy (progesterone)
• Medications: Anticholinergic drugs, Nitrates, Calcium channel blockers, Prostaglandins (pain medications)

We often experience Transient Relaxation of the LES. This means the weakness doesn’t persist, it's only there for 5-30 seconds [3], 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 which result in over production of stomach acid. These conditions are relatively uncommon; most people taking 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 [4]. A condition called Zollinger-Ellison Syndrome is the most common type, representing 30% [1] of that tiny 3%.

After Prolonged Use of Acid Blockers

When we have low stomach acid, our stomachs will make more gastrin, which is a signal to make more acid. The gastrin will get to its highest point (15% higher than it is supposed to be) around the 4^th month of treatment [1]. Once a person stops the acid blocker, they experience a transient over secretion of acid early on. Luckily, this tends to only last for about 7 days [1].

H. Pylori

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 [1].

Summary

Although acid reflux is often treated with acid blocking medications, it's usually not from over production of acid. The most common cause of acid reflux is lower esophageal sphincter dysfunction. Treatment with antacids is appropriate to block the symptoms but addressing the underlying issues should be the top priority. Book in with our naturopath to discuss how we may work towards ideal gut function!