Side Sleeping: Which Side Is Best?

The Health Benefits of Side Sleeping

We spend about one-third of our lives sleeping. When you sleep soundly, your body has a chance to rejuvenate and recover from the previous day's activities. While sleeping, your body may move around in various positions, and the most common sleep position is side sleeping.

Experts agree that sleep is an important aspect of living, and most people are not getting enough sleep. In fact, the Centers for Disease Control (CDC) reports that about 35% of people get less than seven hours of sleep a night and that about 1 in 20 people has fallen asleep at the wheel while driving. So getting the best sleep each night should be one of your main goals.

Could your sleep position be affecting your health? Is there a better (or best) way to be sleeping? If so, which position is best for you, and which side should you be sleeping on?

This article will look at how your sleeping affects your health and examines if there is a sleep position that is best for you.

woman sleeping on her left side

Adene Sanchez / Getty Images

How Sleep Affects Health

Getting a good night's sleep—seven to eight hours worth—can help you feel good, but it can also have an effect on a variety of your body's systems.

From a cognitive standpoint, not getting enough sleep may affect how your brain functions. Problems may include:

Other problems may also cause these impairments, so be sure to see your healthcare provider if you experience any of these.

Lack of a good night's sleep may also have an effect on your heart health. It may cause changes to your heart rate, leading to tachycardia (elevated heart rate). It may also lead to high blood pressure.

Poor digestion may also be associated with disturbed sleep or sleeping in a position that is not conducive to adequate digestion. Heartburn may also result from poor sleeping positions.

What Is Side Sleeping?

Side sleeping occurs when you avoid sleeping on your back or on your stomach and you choose to sleep on one side or the other. Sometimes people choose to sleep on the right side, and other times choose the left side. Some people spend some of each night on one side and then switch to the other.

There are some people who choose to sleep on one side. Sometimes, someone may sleep so soundly that they move to one side without knowing it; they simply wake up on their side.

There are some health benefits to side sleeping regardless of which side you choose. Side sleeping may help with brain health, helping to distribute toxins throughout the brain so your body can eliminate them. It may also help keep your spine in alignment, leading to less low back or neck pain.

But, there may be a good reason to choose to sleep on your left or right side only.

Left Side

Sleeping on your left side means that your left shoulder is down while sleeping and your right shoulder is up. There may be more positive health benefits to sleeping on the left side when compared to the right side or in the supine (on your back) or prone (face down on your stomach) positions.

Benefits

There are several potential health benefits to sleeping on your left side. If you are pregnant, many experts recommend left-side sleeping for comfort and to improve blood flow to your intestines and uterus. This may keep your baby happy and make your time during pregnancy more comfortable.

Sleeping on your left side may also provide relief from heartburn symptoms. It is thought that sleeping on your left side puts your stomach and esophagus in the best position to reduce gastro-esophageal reflux disease (GERD). (Some people with GERD are able to sleep on their right side with no problems.)

It is also thought that sleeping on your left side places the lower esophageal sphincter in an elevated position relative to the stomach (and its acidic contents), which can improve digestion. The stuff you ate last night can rest comfortably in your stomach juices and digest properly while you sleep.

Right Side

Sleeping on the right side means that the right shoulder is down, and there may be a few health benefits for this position. Believe it or not, there is some—albeit limited—research that right side sleepers are more relaxed and experience fewer nightmares than left side sleepers.

Benefits

One of the benefits of right-side sleeping is that it may decrease nervous system activity. It is not clear why this happens, but it may lead to decreased anxiety and depression.

Decreased nervous system activity during right-side sleeping may lead to lowered blood pressure and heart rate as well. This can be especially helpful for people with cardiovascular disease. Surprisingly, some research has indicated that people tend to gravitate to right-side sleeping naturally as they age. This is thought to be an automatic mechanism for controlling heart rate and blood pressure, protecting the aging heart.

Sleep Positions to Avoid

There are a couple of sleep positions that should be avoided if at all possible. If you have neck pain, then sleeping on your stomach is not recommended. When you are prone, you have to have your head cranked to one side or the other to breathe. Spending long periods of time with your neck heavily rotated in one direction may cause pain and stiffness in your cervical spine.

If you snore or have sleep apnea, you may want to avoid sleeping on your back. Sleeping supine may cause your uvula to move towards the back of your throat, leading to snoring or to loss of oxygen intake during sleep. This leads to sleep that is not as restful as it should be for optimum health.

If you have glaucoma, recent research has found that sleeping on your side may elevate eye pressure. One study found that the eye that is down (left eye for left side sleepers) demonstrates an increased eye pressure when compared to the upper eye in side sleepers. If you have one sided glaucoma, you should sleep with the affected eye up.

Staying in the side sleeping position may be challenging, so you may need to experiment with using propping pillows or a long body pillow to remain in the side position. It often takes a few tries to find the best pillows and positioners for you.

Summary

As you sleep, you may move around a bit or remain in one position. If you are able to, sleeping on your side may be the best option for you. There may be specific health benefits to sleeping on your right or left side, and you can optimize these benefits by working to remain in the side sleeping position during the night. There is varied research into which side is best for any condition. Bottom line: the best position for you is the one that gives you optimum and restful sleep each night.

A Word From Verywell

Sometimes side sleeping is a must if you have certain medical conditions, and occasionally side sleeping happens without you being aware. If you have certain conditions, you should choose to sleep on one side or another to maximize the health benefits of sleeping in that position. Work with your healthcare provider to ensure that you choose the best side for your specific situation.

Frequently Asked Questions

  • How can you avoid hip pain when sleeping on the side?

    To keep your hips comfy while side sleeping, place a small towel to act as a cushion underneath your bottom hip. You may also slightly rotate your pelvis forward by placing your top leg on top of a pillow. This may place your bottom hip in a slightly better position without having the weight of your pelvis upon it.

  • How can you relieve shoulder pain from sleeping on the side?

    Keeping your shoulders in a neutral position can help maintain comfort while sleeping. Pillows and bolsters to rest your arms upon can help, and working with a physical therapist (PT) may be an option. Your PT can show you stretches that can relieve shoulder pain that may occur from side sleeping.

  • Where should you put your arms when sleeping on your side?

    Your top arm can rest comfortably on a pillow that is draped over the side of your body. To place your bottom arm in a comfortable position, slightly rotate your torso so your bottom arm comes forward. This takes the weight of your body off your shoulder joint.

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Brett Sears, PT
Brett Sears, PT, MDT, is a physical therapist with over 20 years of experience in orthopedic and hospital-based therapy.