Dr. Hayden says to avoid sleeping on your stomach. "Many stomach sleepers present with severe neck problems in midlife," he explains. "In order to sleep in the prone position, you must turn your head to breathe, which places tremendous stress on the joints in the neck while the muscle tone that protects the joints is greatly reduced. The joints will wear out, which can manifest by disc disease, bone spurs, and possibly extremity pain. This can be avoided just with proper alignment during rest."