Sleep Resources

What is the Best Side to Sleep On?

If you want to truly get a good night’s sleep, then we urge you to check out this comprehensive breakdown of expert-recommended sleeping positions.

By Alex Reale

Mattress Nerd consulted Dr. Tom Ingegno, DACM, MSOM, LAC, to ensure that this article met our editorial standards

Are you having trouble falling asleep and staying asleep, or do you find yourself waking up with aches and pains on a frequent basis? The root cause of these medical conditions may lie in your preferred sleep position. In fact, the quality of your sleep experience can depend entirely on which side you prefer to sleep on. Believe it or not, if you’re one of the majority of people who sleeps on their side, then you may be shocked to know that it does actually matter if you’re a right-sider or left-sider. Keep reading to get an idea of why it may be time to switch sleep sides.

Avoid Your Right Side

As shocking as it may sound, there is in fact a stark difference between sleeping on your left and right side, and you should ultimately avoid sleeping on your right side if you want to maximize your sleep experience, both from a comfort perspective and a wellness perspective.

To understand why your left side is one of the best sleeping positions, we need to consider the way the human body is set up. Our organs, especially those focused on digestion, are positioned in such a way that sleeping on the right side can actually work against our bodily functions, whereas left-side-sleeping does the opposite. Here are just some of the ways sleeping on your left side can benefit you in the long run.

Digestion: When we’re digesting food, our small intestines push waste through to our large intestines via the ileocecal valve, which is located on the lower right end of our abdomen. Sleeping on your left side allows for gravity to assist with the transfer, while sleeping on your right side is akin to trying to push a boulder up a hill.

Esophageal health: Have you ever woken up with bad heartburn? If you have, and you tend to be a right-side-sleeper, then this can be attributed to a theory revolving around gastric juices in our stomach. Sleeping on our left side allows these acidic juices to remain lower in your esophagus as you sleep, so you don’t need to worry about wet burps and other nasty acid reflux-related symptoms.

Brain health: It’s not just your stomach and intestines that have to deal with waste. Our brains are also filled with all kinds of gunk, namely interstitial waste. By sleeping on your left side, you can aid your brain in cleansing this waste, which can potentially reduce your risk for brain-related disorders and diseases such as Alzheimer’s, Parkinson’s, and more. Speaking of brain health, make sure you take a look at our best pillows for side sleepers list.

Breathing: Many people suffer from breathing issues in their sleep such as obstructive sleep apnea or the tendency to snore. By sleeping on your side, you can prevent your tongue from falling into your throat and blocking your airway. Related: Understanding Sleep Apnea.

Pregnancy health: Sleeping while pregnant can be a real challenge. Pregnant women are advised to sleep on their left sides in order to optimize blood flow for themselves and their babies, reduce the chances of health problems such as GERD (gastroesophageal reflux diseases), and lessen the amount of pressure on the spine. For more information, take a look at our best mattresses for pregnant women roundup.

These are just a couple of the benefits that come with left-side-sleeping. If you’re not a left-side-sleeper yet, it may be a good idea to start transitioning. However, if you want to really get an excellent sleep experience, plenty of evidence points to back sleeping as the best sleep position.

Related: Best Mattresses for Side Sleepers

Back is Still Best

A very common sleep problem that people face is waking up in the morning with back pain. While this can sometimes be attributed to the type of mattress or pillow you use, you need to also consider your position. If you’re ready to say goodbye to lower back pain and related issues, and if you want to have an overall better sleep experience, then we urge you to consider trying back sleeping.

By sleeping in a neutral position such as on your back, you’re doing your spine a massive favor. Gravity is helping your entire body center over your spine, preventing any additional stress on sensitive areas. If you want to assist with your back pain reduction efforts, you should look into placing a pillow underneath your knees. This can help with maintaining the natural curve of your body while also reducing additional weight placed on your spine.

Aside from optimal spinal alignment, another potential health benefit of sleeping on your back is the reduction of heartburn, but in order to take full advantage of this benefit, you’ll want to make sure you have a proper pillow as well to keep your head and neck elevated. Similar to how we talked about side sleeping helps keep gastric juices lower in your esophagus, this can also help with preventing them from coming up higher in your throat and causing acid reflux.

One additional benefit of sleeping on your back is that it can help with skincare. Stomach sleepers and side sleepers keep their faces pressed against the pillow all night long. Even if you wash your pillowcase on a frequent basis, if you’re stomach sleeping, you can still experience issues with your skin, like clogged pores and dryness. By sleeping on your back, your face may not face such problems. If you’re interested in trying, take a look through our guide on how to train yourself to sleep on your back.

Related: Best Mattresses for Back Sleepers

Changing Sleep Positions

Sleeping on your back can be extremely beneficial for you, but if you’re not used to it, it can be difficult to transition. Luckily, there are simple methods you can try to assist with your conversion to a new, more worthwhile position.

First off, you’ll want to make sure you’re using the right mattress. Back sleepers want to pick a new mattress that is higher on the firmness scale, because a softer mattress will cause their hips to sink in, throwing off the natural curve of the body. Our best firm mattresses guide has some options that we think work great for back sleepers.. You’ll also want to pick a firm pillow that keeps your head elevated at just the right level, but nothing too firm, as over-elevation can cause neck pain. Remember, the key to proper back sleeping is spinal alignment. 

Next step to transitioning to back sleeping: as you’re falling asleep, spread out your arms and legs, almost like a starfish. Most people make the mistake of strictly sleeping in a straight line with their arms and legs bunched up against their bodies, which can lead to joint pain and accidental rollovers. Sleeping with your limbs outstretched can keep you on your back and help with distributing your weight, leading to less joint pain and less pressure on your spine.

We mentioned earlier how placing a pillow under your legs while you sleep can help with spinal alignment, but it can also assist with your mission of becoming a back sleeper. Our body may force us to roll off our back because it senses pain or discomfort in the spine. To prevent this from happening, you can use a pillow under the knees to relieve excess spinal pressure – just make sure it’s not a flat pillow! 

Another tactic is to build a pillow fort. To do this, you just need to place a set of pillows on either side of your body, almost like a barrier. This wall of pillows will prevent you from inadvertently rolling over onto your side in the middle of the night. 

A similar strategy that you can use in lieu of or in conjunction with the pillow fort is the tennis ball trick. For this method, you just need to place a tennis ball in either one of the pockets of your sleep pants. While you sleep, if you try to roll over, the balls will dig into the sides of your legs, forcing you to remain on your back. It may take a while to get used to this, but with time, it can condition you to maintain the back position all night.


There are many factors that can impact our sleep experience, but if you want to do something to improve your rest sooner rather than later, we recommend working on your sleep posture and position. Start looking into ways you can transition into back or left-side-sleeping so that you can move forward on your journey to a well-deserved, restful sleep. And of course, make sure that you are sleeping on one of the best mattresses for side sleepers.

Meet Our Medical Reviewer

Dr. Tom Ingegno, DACM, MSOM, LAC

Dr. Tom Ingegno, Doctor of Acupuncture and Chinese Medicine, has over 20 years of experience in the integrative and functional medicine space. He owns and operates Charm City Integrative Health, a multifaceted clinic that NYT bestseller and futurist David Houle called, the “Future of Medicine.”