Many people think that firmer mattresses offer more back support than soft ones. But a new industry-financed study found that at least some people with chronic back pain sleep better on a waterbed or body-conforming foam mattress.

Other research suggests that medium-firm surfaces are often best. A mattress that’s too hard might not provide even support and cause achy hips and shoulders, but if it’s too soft you could sink in, which can be equally uncomfortable. Consumer Reports’ research has found that there is no "best" mattress for everyone. So lie on a mattress for at least 15 minutes before buying it.

This article first appeared in the July 2008 issue of Consumer Reports On Health.

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