What's the Best Pillow Setup for Sleep?

Credit - Illustration by TIME

When most of us think about how to get the perfect night’s sleep, we consider things like how firm our mattress is, how cool or dark our room is, and what time we go to bed. One factor we sometimes fail to consider? Our pillow setup.

“I think pillows are often incredibly overlooked,” says Dr. W. Christopher Winter, a neurologist, sleep specialist, and author of The Sleep Solution.

Winter says he always asks patients what kind of pillow they have and where they bought it. “It’s really surprising how few people can actually answer the question,” he says. “It’s like they just always had the pillow or it just showed up in their bed at some point and they never really questioned it.”

Finding the perfect pillow is an opportunity for people to improve their sleep without buying a new mattress, which can be time-consuming and costly, says Winter, who also hosts the “Sleep Unplugged” podcast.

The following advice can help ensure your pillow setup will get you the best sleep possible.

Not too low, not too high

The most comfortable sleeping position is highly personal. Some people will feel most comfortable sleeping on their stomach, while others will get the best sleep on their side or back. (Generally speaking, side and back sleeping are best for the alignment of the spine.)

Pillow height is highly personal, too; there’s no scientific consensus yet on the ideal pillow height. But a good rule of thumb is to use a pillow that fills the gap between your shoulder and ear, as this helps align your neck and spine, says Craig Hensley, associate professor of physical therapy and human movement sciences at Northwestern University Feinberg School of Medicine.

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“If the pillow is too thick, it will bend and put stress on your neck,” he says. “If it’s not thick enough, it’ll bend your neck the other way, which could compress some of your joints.”

Find the right firmness and material

Most people sleep better with a firmer pillow, Hensley says. Firm pillows support the head and neck better than soft ones. Just beware of a pillow that’s too firm, as this can cause stiffness from hyperextension of the neck, says Dr. Rachel Salas, a sleep neurologist at the Johns Hopkins Center for Sleep and Wellness.

The composition of pillows matters, too. One study compared five different pillow types: polyester, foam, contour foam with a groove for the neck, feather, and latex (which is bouncy and moldable). The study looked at whether each pillow type contributed to participants waking up with a stiff spine, headache, or arm pain. The researchers found that feather pillows performed the worst, while latex pillows performed the best.

An added benefit of latex pillows is that they can protect against dust mites, Winter says. Certain materials, like goose down, are porous, and therefore more likely to trap dust mites than latex pillows.

Replace your pillows and wash your pillowcases regularly

If you wake up congested or with a post-nasal drip, it could be due to allergens in your pillow. One study found that 10% of a two-year-old pillow’s weight is due to dust mites and their excrement. Pillows can also contain dead skin, mold, and pet dander.

“If pillows are old, they can trap a lot of dust mites and human skin, and that can interfere with sleep quality,” Salas says.

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The Asthma and Allergy Foundation of America suggests replacing your pillow every two years. Hypoallergenic covers can be beneficial if you’re particularly prone to allergies.

You should also wash your pillowcases at least once a week. One study found pillowcases that hadn’t been cleaned in a week contained 17,000 times more bacteria than a toilet seat. This bacteria can be particularly rampant if you drool, sleep with makeup on, or sweat a lot.

Strive for a cooling effect

If your head gets too hot while you sleep, your sympathetic nervous system can become activated, according to one 2015 study. This can prevent you from achieving deep sleep, which is essential for health. Using a pillow with a cooling effect can help you sleep better, especially if you’re prone to overheating at night.

If you’re looking for a pillowcase that will keep you cool, avoid synthetic materials like polyester, since they can retain heat, says Dr. Sudha Tallavajhula, medical director of the Neurological Sleep Medicine Center at TIRR Memorial Hermann in Houston. Instead, opt for pillowcases made from natural fabrics like cotton, silk, and bamboo.

Pillows aren’t just for your head

When you picture the perfect pillow setup, it’s important to think beyond just the pillows under your head, Winter says.

Pregnant women, for example, might benefit from pillows that support their abdomen or legs. People with back pain can also benefit from using support pillows on their body. Hensley often recommends people with back pain who sleep on their back put a pillow under their knees, as this can decrease stress on the lumbar spine. People with back pain or sciatica who sleep on their side, he says, should put a pillow between their thighs, as this can lower the stress on the sciatic nerve.

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For those with shoulder pain, Hensley recommends sleeping on the opposite side of the injury, and placing a pillow under the injured shoulder. For example, if you have right-sided shoulder pain, sleep on your left side and place a pillow under your right shoulder.

Many people like to sleep with their arm under their pillow. But doing so can put too much weight on your arm, especially if you have a shoulder injury. If you feel the most comfortable sleeping with your arm under your pillow, consider a specialty pillow that comes with a slot for your arm, Winter says.

Some people will benefit from added height

Most people should only sleep with one or two pillows, Salas says. But there are exceptions to this rule. For example, sleeping slightly more elevated can help pregnant women dealing with shortness of breath and heartburn.

If you have gastroesophageal reflux disease (GERD), your sleep quality will also likely improve if your pillow setup is a little bit higher, Winter says. When you sleep slightly elevated, the contents of your stomach can flow downward more easily. “When we lie flat, they’re more likely to regurgitate through the esophageal sphincter,” he says. “When you’re more upright, gravity holds things down better.” (Tallavajhula adds that sleeping on the left side is better for people with acid reflux due to the position of the stomach.)

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Snoring can also improve if you use a pillow that’s a little bit higher. Snoring is often a sign of obstructive sleep apnea, a condition in which the airway becomes blocked and our breathing pauses. Sleep apnea should be treated with a CPAP machine. (Companies now make pillows that accommodate CPAP machines.) Allergies, obesity, and sleeping on your back can also cause snoring. Regardless of why you snore, sleeping with more pillows or a slightly higher pillow can help open your airway and reduce snoring.

“Something as simple as propping your head up can improve snoring, improve sleep apnea, and then it also tends to make elements of GERD much better,” Winter says.

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