Conventional wisdom has been that a firmer mattress is best for neck and back pain. In fact, people in acute pain find that lying on the floor can give them some relief.

According to our 2016 survey of almost 62,000 subscribers, people with arthritis, back pain, and neck pain were happiest when they slept on an adjustable air mattress like a Sleep Number, which lets users precisely control the firmness.

According to Joel Press, M.D., physiatrist-in-chief at the Hospital for Special Surgery in New York, that preference may be because people in pain benefit from being able to adjust a mattress to match the level and type of pain they are experiencing on any given night. Jeffrey Goldstein, M.D., chief of spine service–education at NYU Langone’s Spine Center, says that a customizable mattress might let patients arrive by trial-and-error to the level of firmness that works best.

Though both doctors emphasized that no one mattress is guaranteed to soothe an aching spine, their general advice is indeed to opt for a firmer mattress, or to adjust your mattress to a firmer setting. Research supports that approach.

Another benefit is that a firmer mattress gives you instant feedback, says Press, so you will register exactly where your pain points are and make adjustments. Keep in mind that a mattress that’s more than 10 years old generally can’t offer sufficient support.

A firmer mattress also helps keep your body aligned, something your pillow can help with, too. Your neck should not be bent or twisted: It should form a straight line with your spine. “You wouldn’t walk around all day with your neck at a 45-degree angle,” Press says, so you probably don’t want to sleep that way, either.

Editor's Note: This article also appeared in the February 2017 issue of Consumer Reports magazine.