How does acid reflux happen?

Acid reflux occurs when the lower esophageal sphincter (valve) is not working. This allows acid and food to freely reflux or move backward from your stomach into your esophagus. This happens because your abdomen is in a higher-pressure state than your chest. The symptoms may be exacerbated when you lie flat.

Here's how reflux can happen:

Normally, when you swallow food, it goes from your mouth, down your esophagus and to your stomach. As the food enters your stomach, it passes through a ring-shaped muscle called the lower esophageal sphincter (LES). A healthy LES opens to let food into the stomach and closes to prevent food and stomach acid from backing up.

When the LES is weakened, food and stomach acid can move back up into the esophagus and throat, causing reflux.

Continue Learning about GERD

What Increases My Risk for GERD?
What Increases My Risk for GERD?
No food after midnight! That was one of the “rules” for avoiding trouble that down-and-out Rand (Hoyt Axton) was given when he bought an extraterrestr...
Read More
What medications treat gastroesophageal reflux disease (GERD)?
Univ. of Nev. School of Medicine, Family MedicineUniv. of Nev. School of Medicine, Family Medicine
Many over-the-counter medications treat GERD through different ways. There are antacids, which neutr...
More Answers
Are there healthy reasons why the valve involved in GERD opens?
Dr. Mehmet Oz, MDDr. Mehmet Oz, MD
The valve between your esophagus and stomach that opens to let acid back up in GERD also opens for h...
More Answers
What Is Throatburn Reflux?
What Is Throatburn Reflux?

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.