What Causes Acid Reflux at Night?

Acid reflux happens when the muscles at the lower part of the esophagus, called the lower esophageal sphincter, which stop food from leaving the stomach, become weak or relaxed. During the day, you are more likely to be upright, standing or sitting up. So when stomach acid escapes, gravity and saliva quickly return the content to the stomach. You’re also more likely to manage GERD symptoms by staying upright, swallowing saliva, or taking antacids when you’re awake. 

Evidence shows that acid reflux usually happens in the first two or three hours of sleep. It usually occurs when a person lays down soon after consuming heavy meals. Studies suggest that those with GERD are more likely to experience acid reflux when they consume heavy meals late at night (about two hours before bedtime). Other factors that may trigger acid reflux include consuming fatty foods, spicy foods, alcohol, and caffeine, smoking tobacco, stress, pregnancy, weight gain, and taking drugs that affect the functioning of the esophagus like anticholinergic drugs (e.g., antidepressants and muscle relaxants) and anti-inflammatory drugs (like diclofenac and ibuprofen).

Acid Reflux Sleeping Positions 

The way you sleep can directly affect how often you feel symptoms, how severe those symptoms are, and how long the acid sits in your esophagus. 

• Left Side

Sleeping on your left side is the best sleeping position for acid reflux. Gravity will work in your favor on your left side as your stomach stays below your esophagus, making reflux more difficult. Should stomach acid escape, gravity can return it to your stomach quicker than when on your right side or on your back, which is why the left is usually the best side to sleep on to avoid acid reflux. Plus, lying down on your left side produces reflux symptoms that tend to be more gaseous, which may be annoying but much less distressing than liquid reflux that comes with lying down on your right side. Studies show that symptoms are less frequent and less severe when a person sleeps on their left side rather than their right side or back, making it a more desirable sleep position for people with GERD.

• Incline + Left-Side

Sleeping at an incline means sleeping with your head elevated 6 to 8 inches off your body by putting extra pillows under your head and upper back. According to an article published in the journal Missouri medicine, head of bed elevation (sleeping at an incline) is proven to manage GERD. It limits how often stomach acid escapes to the esophagus, allows your body to get stomach acid back to your stomach quicker, and reduces the symptoms of GERD. Likewise, a 2012 study suggests that elevating the head while lying down may reduce nighttime acid reflux and help manage heart burn and poor sleep from nocturnal gastroesophageal reflux.

Combining the left-side sleep position with an incline can be the best sleep position for acid reflux. The compound inclined, left-side sleeping position makes acid reflux at night virtually impossible because your esophagus is now positioned well above the level of stomach contents, even if your stomach is full. And, if you do reflux, gravity can quickly return the contents to your stomach. This sleep position may decrease your GERD symptoms and protect you from prolonged acid exposure to your esophagus, throat, lungs, and sinuses.

Sides to Avoid Sleeping on for Acid Reflux

Sleeping positions that may be the best for some could aggravate GERD symptoms and impair sleep in people with GERD. Here are two sleeping positions people with GERD should avoid:

• Back Sleeping: Avoid Whenever Possible

Sleeping on the back increases how often acid reflux happens at night. When you sleep flat on your back and acid escapes from your stomach, it can flow freely into your esophagus and remain there. Studies show that symptoms are often more frequent in this position and tend to last longer because the acid cannot flow back to the stomach. 

Your symptoms may also be more severe if you have stomach fat, which pushes down on your stomach, forcing contents to escape. Back sleeping should be the #1 position to avoid at night if you suffer from nighttime acid reflux.

• Right Side: It’s Not Right for Acid Reflux

Position #2 to avoid at night is sleeping on your right side. When lying on your right side, your stomach is actually above your esophagus, creating a leaky faucet spouting stomach acid into the delicate lining of your esophagus. This is especially true when your stomach is full. Interestingly, when lying flat on your right side, your reflux symptoms tend to be more liquid, leading to regurgitation, coughing, and choking, which can be very devastating in the middle of the night. Since gravity is doing nothing for you in this position, the amount of time acid lingers in your esophagus is much longer. A study showed that people who sleep on their right side get an earlier diagnosis of GERD when they have it than those who sleep on their left, which is telling on how severe nocturnal GERD symptoms are when a person sleeps on their right side.

Additional Tips to Control Acid Reflux at Night

In addition to adjusting your sleep position, you can make lifestyle changes that may help manage acid reflux at night and promote a well-rested night. Some of these lifestyle recommendations include:

• Limiting alcohol intake, heavy meals, fatty meals, and nighttime snacks

• Eating in the early hours of evening time

• Managing bodyweight if you’re overweight or obese

• Quitting smoking 

• Avoiding drugs that may limit the functioning of the esophagus like non-steroidal anti-inflammatory drugs (NSAIDs)

A doctor may also prescribe medications or recommend surgery to treat GERD when appropriate. Talk with your doctor about your symptoms so they can prescribe treatment or lifestyle recommendations to manage your condition and improve your sleep health.

Proper sleep positioning can help control your acid reflux symptoms at night and improve your sleep quality. The best sleeping position for acid reflux is the left-side sleep position, combined with an incline. Avoid sleeping on your back and right side, as these positions tend to worsen GERD symptoms. Lifestyle changes, such as limiting alcohol intake, heavy meals, fatty meals, and nighttime snacks, eating early in the evening, managing body weight, quitting smoking, and avoiding drugs that affect the functioning of the esophagus, may also help manage acid reflux at night.