What's the best sleep position? Experts explain back, side and stomach sleeping

You went to bed feeling fine — so why, eight hours later, do you wake up like you've been in a fight and lost? Your neck is twisted into a pretzel, your lower back is screaming and your partner's giving you the side-eye because you sounded like a chainsaw all night. Surprise: Your sleep position might be to blame.

But here's the tricky part — there's no universal "best sleep position" or single best way to sleep that works for everyone. The right one depends entirely on your body and your needs — whether that's back pain, neck pain, shoulder pain, snoring, acid reflux or pregnancy. And it gets more complicated because a sleep position only works as well as the pillow and mattress supporting it. That means you could sleep in the "right" position for your body and still wake up feeling wrecked if the rest of your setup isn't doing its job.

That's where understanding the mechanics helps. Once you understand how different positions affect your body — and how they influence your spinal posture overnight — you can do something about those morning-after regrets. Yahoo talked to sleep experts and doctors to break down what works, what doesn't and how to figure out if your nightly habits are the culprit behind your daytime discomfort.

What are the most common sleep positions?

The three main sleep positions are side sleeping, back sleeping (also called supine) and stomach sleeping (prone). But chances are, you're a mix of these positions — including variations like the "starfish position," where back sleepers lie with their arms raised near their head or pillow, a position about 7% of people favor .

"Most people don't sleep the same way all the time, and we change sleeping positions subconsciously throughout the night," explains neurobiologist Major Allison Brager , an assistant professor at the United States Military Academy at West Point who specializes in sleep and circadian rhythms.

Sleep position problems usually show up when you spend too much time in one position without proper support from your mattress or pillow. Think of it like sitting in a chair all day. Even a high-quality ergonomic chair can cause you pain if your desk's too high, your monitor's positioned wrong or your keyboard is at an awkward angle.

Side sleeping

For some, side sleeping can be a genuinely helpful sleep position — but only when your spine, shoulders and hips stay aligned throughout the night, maintaining healthy sleep posture.

Side sleeping is best for those who …

• Snore or have mildsleep apnea. Side sleeping can help keep airways more open than back or stomach positions, which is why it's commonly recommended by sleep specialists .

• Have acid reflux or frequent heartburn . Sleeping on your left side tends to reduce reflux, while right-side sleeping may worsen it. "In that position, the stomach is above the esophagus, which can lead to increased acid reflux events and heartburn due to gravity," says Dr. Keith Summa , an assistant professor at Northwestern University Feinberg School of Medicine. That advice is backed by research using overnight pH monitoring, which shows less acid exposure and faster clearance when people sleep on their left side.

• Are in the later stages of pregnancy (around 28 weeks or later).Side sleeping is recommended to avoid prolonged back sleeping. While the left side is often emphasized, evidence suggests that right-side sleeping is also considered safe.

• Have a deviated septum or nasal congestion.Experts at the Cleveland Clinic note that side sleeping may help.

Who should avoid side sleeping

Wake up with your shoulder screaming? Or maybe it's your neck, your hip or that weird numbness in your arm instead. In those cases, side sleeping might be the problem — not the solution. If your mattress doesn't allow your shoulders and hips to sink in evenly while still supporting your waist, you can end up sleeping on a subtle slope all night long. And that's not exactly a recipe for waking up feeling good.

Pillow and mattress considerations for side sleepers

When it comes to choosing the best mattress for side sleepers, spinal alignment is key — and it matters even more than whether your mattress is soft or firm . That said, side sleepers tend to prefer a slightly softer mattress to cushion their shoulders and hips while preventing the spine from sagging into a curve.

To help with alignment and pressure, pull your legs up slightly toward your chest and slide a thin pillow between your thighs and knees to help keep your hips balanced. This can reduce pressure on your spine by nearly half, according to the National Spine Health Foundation . For your head, try a thick pillow that keeps the top portion of your spine straight and parallel to the mattress .

Back sleeping

Back sleeping doesn't get enough credit. Snoozing this way "promotes an even distribution of your body weight, which can limit pressure on your spine by keeping it balanced," says Summa.

Back sleeping is best for those who ...

• Deal with neck pain.Sleeping on your back keeps your head and neck in a neutral position, rather than cranked to one side. "There's a lower risk of neck and shoulder misalignment this way," says Summa.

• Have certain types of lower back pain .This position can reduce strain on the spine, especially when the lower back is properly supported. In fact, sleeping on your back puts the least pressure on your spine .

• Toss and turn at night.It's generally easier to change positions from your back than from your side, which can help restless sleepers settle more comfortably.

Who should avoid back sleeping

If you snore regularly or have sleep apnea , back sleeping is your worst option. Gravity pulls the soft tissues at the back of your throat downward, which can block your airway and make breathing even harder, notes Summa. Untreated acid reflux is another reason to skip this position, as lying flat makes it easier for stomach acid to flow up into your esophagus, making symptoms worse.

Pillow and mattress considerations for back sleepers

Your mattress should support your lumbar curve without creating a gap between your lower back and the bed. Medium to medium-firm mattresses often work well here, though it's not a hard-and-fast rule.

As for pillows, Mayo Clinic sleep experts suggest placing a pillow under your knees to help relax your back muscles and maintain the curve of your lower back. (Need even more support? Place a small, rolled towel under your waist.) Finally, pick a head pillow that supports your neck and lets your head sink in.

Stomach sleeping

If there's one position experts universally frown on, it's stomach sleeping. And for good reason: It places the most pressure on your lower back .

Stomach sleeping is best for those who ...

It's a very short list. However, Carleara Weiss , a sleep scientist and assistant professor at the University at Buffalo, State University of New York, says that sleeping on your stomach may help people with certain lung diseases or difficulty breathing by releasing pressure on the lungs. But that's about where the benefits end.

Who should avoid stomach sleeping

Pretty much everyone else. If you wake up with neck pain, lower back pain or just feel stiff all over, stomach sleeping is probably why. You're forcing your head to stay turned to one side for hours (hello, neck strain), and depending on your mattress, your back can end up overextended all night, says Weiss.

Pillow and mattress considerations for stomach sleepers

If you're committed to stomach sleeping, a firmer mattress can help prevent your spine from over-arching. Placing a thin pillow under your lower abdomen can also support spinal alignment. As for your head, skipping a pillow altogether is ideal — but if that's not realistic, use the thinnest one possible to minimize neck strain.

How to know if your sleep position is causing pain

There's an easy way to tell if your sleep setup is the issue. Notice when your pain is worst. If you're stiffest right when you wake up but loosen up once you start moving, your sleep position or mattress is probably working against you.

Finding what works — and learning how to sleep in a way that supports your body — requires some detective work. Summa recommends "paying close attention to your body" and testing different positions systematically. When you lie down each night, do a quick body scan for tension or discomfort. Try one position for a full week, noting areas of tension or discomfort each night, before deciding whether it's a keeper, says Summa.

How to change your sleep position

Changing a sleep position you've had for years isn't easy, but it's doable. Here's how to start.

Use pillows

Experts at the Cleveland Clinic recommend looking for a pillow tailored to your sleep position. For help zeroing in on yours, take a look at Yahoo's tried and tested best pillow picks , including body pillows and wedge pillows.

• If you're trying to become a side sleeper,place a pillow along your back or front to keep you from rolling onto your back or stomach. "Pillows provide proprioceptive reinforcement to sleep on your side," Brager explains. In other words, they act as a physical barrier that your body bumps into when you try to roll, training you to stay put.

• If you're trying to become a back sleeper,place both arms in the same position to keep your spine aligned. You can also place pillows around your midsection and hips to prevent you from rolling over during the night.

Consider your mattress

If your current mattress is old, sagging or too soft or firm for your needs, no amount of pillow-arranging will fix the underlying problem. When in doubt, consider shopping around for a new mattress. Use our expert guides to find a bed that works for you:

• How to choose a mattress

• Mattress types explained

• Mattress firmness: A guide to mattress firmness options

• Mattress Sizes: dimensions, differences and how to choose the right one

• How to buy a mattress online

Give it time

If you've been sleeping the same way for years, your body needs time to adjust. Give yourself at least a few days to a few weeks to adapt to a new position before deciding it's not working.

FAQs

What's the healthiest sleep position overall?

The best sleep position for you depends on your body and whatever health issues you might be managing. However, here's the general hierarchy of preferred sleep positions, according to the Cleveland Clinic :

• Back sleeping:This position puts the least pressure on the spine and is often preferred from a body-alignment standpoint.

• Side sleeping:Sleeping on your side is considered an acceptable alternative — and is often recommended for people who snore or have sleep apnea.

• Stomach sleeping:This position is generally discouraged, as it places the most strain on the spine and neck.

No matter which position you choose, the key is to ensure your spine is naturally aligned – that's where mattress and pillow choice come into play.

What does my preferred sleep position say about me?

Not much, honestly! Your sleep position is more likely to be influenced by physical comfort, pain patterns and health conditions than by personality traits. So don't read too much into those viral posts claiming back sleepers are confident, or side sleepers are sensitive. Your body chooses positions based on what feels physically sustainable, not whether you're an introvert or an extrovert.

What is the best sleep position for back pain?

While Summa recommends sleeping on your side in a comfortable, aligned and well-supported position to help minimize neck and back pain, it's not a universal recommendation. In practice, the most beneficial sleep positions for your back are either sleeping on your side (with your knees partially bent and pillows tucked between your legs) or on your back — provided you don't have sleep apnea — with a pillow under your knees.

What's the best sleeping position for sciatica?

While there's no best sleeping position for sciatica pain , you can adjust your current sleep position to be more comfortable:

• Sleeping on your backpromotes proper spine alignment, which can offer nighttime relief. To help ensure your head, shoulders and hips are in a straight line, place a small pillow under your neck and head — not your shoulders. Also, try sliding a pillow under your knees.

• Sleeping slightly elevatedcan help if spinal stenosis is behind your sciatica. Simply slide a large wedge pillow under your head and upper back.

• Sleeping in the fetal position,on your side with knees curled up, can also help with spinal stenosis

• Sleeping on your sidecan take pressure off your sciatic nerve. It's best to lie on the side opposite your pain and to place a pillow between your knees.

Is it bad to sleep on your stomach every night?

Generally speaking, yes, as the mechanics of stomach sleeping aren't great. Your neck stays rotated for hours, and your back can arch excessively depending on your mattress type. Stomach sleepers run the risk of developing lower back pain over time. But if you've made it this far without issues, you might be the exception. Just pay attention to any new aches that crop up as you age.

Can my sleep position worsen health concerns like sleep apnea or heartburn?

Unfortunately, yes. Back sleeping often makes snoring and sleep apnea worse . It can turn manageable snoring into a full-blown breathing obstruction because gravity pulls the back of your throat closed. And if you have heartburn, lying flat creates a highway for stomach acid to travel straight up your esophagus. Right-side sleeping makes reflux even worse since your stomach ends up positioned above your esophagus. So if you have these conditions, position matters a lot.

What is the best sleep position during pregnancy?

Side sleeping is generally recommended during the second and third trimesters. That's because lying flat on your back later in your pregnancy can put pressure on major blood vessels, which may make you feel dizzy and reduce blood flow to the uterus, according to the American College of Obstetricians and Gynecologists . Research suggests this guidance becomes especially important after about 28 weeks.

For comfort and support, ACOG recommends placing a pillow between your knees and another under your belly, or using a full-length body pillow. As Summa points out, those pillows also help counter the lower back strain from your uterus weighing you down.

Meet our experts

• Major Allison Brager ,PhD, neurobiologist and assistant professor at the United States Military Academy at West Point

• Carleara Weiss, PhD, RN, sleep science and assistant professor at the University at Buffalo, State University of New York

• Keith C. Summa ,MD, assistant professor at Northwestern University Feinberg School of Medicine in Chicago