In the past, we’ve written a lot about GERD and other esophageal diseases that are caused by a weak or damaged lower esophageal sphincter. But, we’ve never really focused on what causes the LES to weaken, or to damage, eventually resulting in an acid reflux disease.

Although we can’t always control the factors that cause our lower esophageal sphincter to deteriorate, there are some things we can do to make sure we are caring for our LES, particularly if we fall under the risk factors for GERD.

Here’s everything you should know about the lower esophageal sphincter and how to prevent it from becoming damaged.

What Is The Lower Esophageal Sphincter?

The lower esophageal sphincter, or LES, is the muscle that connects the esophagus to the stomach. This muscle remains closed the majority of the time, only opening to let food through to the stomach or to regurgitate stomach gas.

If a person’s LES is weak or damaged, though, the muscle can lose its ability to close (as with GERD), or it’s ability to open (as with Achalasia). When the LES fails to close, it allows stomach acid to splash up from the stomach into the esophagus, causing severe acid reflux and heartburn.

On the other hand, when the LES fails to open, swallowing food becomes very difficult. Both of these conditions are very challenging and can only be cured with surgery.

What Causes A Weak Lower Esophageal Sphincter?

There are a variety of reasons why the lower esophageal sphincter may weaken, and most of these are preventable. Here are a few of the preventable factors that lead to a weak LES.

Overeating Or Being Overweight

When a person regularly overeats or is overweight, their stomach swells and puts a lot of extra pressure on the LES. Over time, the LES loses its shape and its strength, allowing acid to flow upward, causing further damage to the LES.


Smoking exposes the esophagus to a lot of toxins and chemicals that damage the membranes in the LES, causing it to weaken. In addition to this, smoking raises the acidity of stomach fluids which can impact the LES more strongly than regular stomach acid.

Drinking Alcohol

Alcohol is known to be a trigger for people with GERD, but for those who do not have it, regular consumption of alcohol can reduce the LES’ ability to close. Alcohol relaxes the muscles in the LES and allows stomach acid to flow upward, which over time also causes considerable damage to the LES.

Certain Medications

There are a number of medications that can damage your LES by causing it to relax. If they are consumed regularly, the LES will remain relaxed and result in acid reflux, causing damage to the muscles and membranes. Blood pressure medication, sleeping pills and sedatives, antibiotics, antidepressants, iron and potassium supplements, and proton pump inhibitors, all cause damage to the LES.

Certain Foods

Trigger foods are something people with GERD always have to avoid, but if you feel that you are at risk for developing GERD, you will really want to avoid certain foods as well. High-fat foods, for example, tend to cause the LES to relax. Cutting how much high-fat foods you consume every day can help protect your LES.

More Information

If you suffer from heartburn and acid reflux more often than you’d like, then you may want to protect your lower esophageal sphincter from all of these risks. Not all heartburn and acid reflux is a symptom of GERD, but if your diet and lifestyle often trigger episodes of heartburn and acid reflux then you may be causing damage to your LES and developing GERD. To learn more about gastroesophageal diseases, contact us today, or book an appointment.