Sleeping Beauty was on to something: A good night’s sleep (i.e., 6.5-8 hours) really does increase your attractiveness. In a Swedish study, a research team photographed 23 healthy adults who were either fully rested or sleep-deprived. When they showed the photos to a different group—65 untrained observers who rated them for health, attractiveness and tiredness—the sleepy subjects were consistently rated as looking more tired, less healthy and less attractive. Makes sense, since sleep is also proven to clear skin, fight wrinkles and reduce inflammation.

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