Some people believe your preferred sleeping position can reveal truths about your personality, mental health, and even the state of your romantic relationships — but the science on that is somewhat shaky. What researchers have uncovered is that the way you sleep could affect the quality of your digestion. Sleeping on your side is thought to enforce a more comfortable positioning of a valve in your intestine and the gastric juices in your esophagus. The latter theory is supported by studies that show a lowered incidence of heartburn in those who sleep on their side. Some results even show that sleeping on your left side is even more beneficial than sleeping on your right.