Next time you wake up in a cold sweat, pay attention to your sleep position. This article from Van Winkle’s tipped us off to a series of studies that compared the types of dreams we have with the way we sleep. One small study (63 participants) found that people were much more likely to experience nightmares (and lower overall sleep quality) when lying on their left side.
Another larger study (670 participants) found that people had the most vivid and generally pleasant dreams sleeping facedown (though some of those face-planters reported dreams of drowning or seeing UFOs).
Science hasn’t found one optimal sleep position—and these studies show correlation, not causation. But if you find yourself having nightmares again and again, rolling over can’t hurt.