You have likely seen the headlines: “Doctors Warn: Your Sleeping Position May Affect Acid Reflux Symptoms.” While it may sound surprising, research suggests that the way you sleep can influence how often stomach acid travels back into the esophagus during the night.

For people who experience heartburn, acid reflux, or nighttime indigestion, understanding the relationship between sleep position and digestion may help improve comfort and sleep quality.

Why Sleeping Position Matters

To understand why sleep posture can affect reflux, it helps to look at how the digestive system works.

The esophagus is the tube that carries food from your mouth to your stomach. At the junction where the esophagus meets the stomach is a muscular valve called the lower esophageal sphincter (LES). Its job is to allow food into the stomach and then close to prevent stomach contents from moving back upward.

When the LES becomes weakened or relaxes at the wrong time, stomach acid can flow back into the esophagus, creating the burning sensation known as heartburn.

During the day, gravity naturally helps keep stomach contents where they belong. At night, however, lying down removes that advantage, making sleep position much more important.

The Best Position: Sleeping on Your Left Side

Many digestive specialists consider left-side sleeping the most favorable position for people with acid reflux.

The stomach sits primarily on the left side of the body. When you sleep on your left side, the stomach remains positioned below the esophagus, making it more difficult for acid to travel upward.

Studies have shown that left-side sleeping may reduce acid exposure in the esophagus and decrease nighttime reflux episodes.

Additional potential benefits include:

• Improved digestion.
• Reduced nighttime heartburn.
• Better sleep quality for some individuals.
• Less pressure on the digestive tract.

The Position Most Associated With Reflux

Sleeping on the right side may increase reflux symptoms in some people.

When lying on the right side, the stomach can be positioned in a way that may allow stomach contents to reach the esophagus more easily. Several studies have found that right-side sleeping is associated with more frequent reflux episodes compared with left-side sleeping.

If you frequently wake up with heartburn, the next section explains another simple adjustment that may make a dramatic difference.