People put a lot of effort into choosing a mattress. But picking the right pillow can be just as important says one expert, Ana C. Krieger, medical director of the Center for Sleep Medicine at NewYork-Presbyterian/Weill Cornell Medical Center. The distance between the neck and bed can make all the difference.

Stuffed with stuff

A pillow should align the hip, back and neck to keep the spine as straight as possible. Amid a wide variety of materials and shapes, including latex, contouring foam and hypoallergenic, Dr. Krieger lumps pillows into just two categories: natural and synthetic. Down and feather pillows can be good because they discourage dust mites and can be molded easily or folded in half when shifting positions during the night. They also tend to stay cool and last long, she says.

Synthetic pillows have the advantage that they keep their shape and height, but they only last about half as long as feather pillows. And Dr. Krieger discourages synthetic pillows with a fixed shape. “If you move out of the position, you’ll be uncomfortable and wake up, and we know you’ll move out of that position,” she says, noting that there is not a lot of hard science focusing on pillows.

Position matters

Side sleepers should choose a pillow that can clear the distance between the shoulder and the ear, to maintain neck alignment. “People who sleep on their side may like feather or down pillows because they can remold,” Dr. Krieger says. “But a slightly firm synthetic might be better to provide consistent support without misaligning the neck,” Dr. Krieger says.

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