Each pillow recycles about 55 plastic bottles, and it comes with a soft eucalyptus lyocell cover that's designed to get softer with each wash.

"A small pillow under the hips ... can also help align the spine" while stomach sleeping, noted Abbasi-Feinberg. (Side sleepers can also try using a small pillow in between the knees.)

Based on Abbasi-Feinberg's suggestion, we chose this lumbar support memory foam pillow, which measures just 5.5 centimeters high. It's designed to promote proper spine alignment during sleep when propped under the waist, and although popular with back sleepers (as shown in the photos) reviewers call it great for stomach sleeping.

Note: Clip the coupon for an extra 10% off at checkout.

Promising review: "I use this pillow constantly. I sleep with it at my hips, and it really helps relax my hip flexors. It stays cool to the touch during the night. I also use it in my office chair for additional lumbar support. The pillow is thick but not overly so you can use it for sitting or sleeping. My only minor concern is that I wish it was wider." -- Haley