Is 'Beauty Sleep' a Myth?
This man had eight hours of sleep before he took the photo on the left, and stayed up all night before he took the photo on the right.
Credit: John Axelsson | Karolinska Institute

Turn out the old beauty sleep adage is right pulling one too many all-nighters really does take its tole on your looks, a new study shows.

People who get eight hours of sleep appear healthier , more rested and more attractive than those who stay up all night, said study researcher John Axelsson, of the Karolinska Institute in Sweden.

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For the study, researchers asked 23 people ages 18 to 31 sleep for eight hours one night and have their picture taken the next day. The pictures were taken between 2 p.m. and 3 p.m. in a well-lit room, with a fixed distance between their faces and the camera.

On another night, those same people got five hours of sleep . Researchers then kept them awake for 31 hours and took their pictures again at the same time of day.

The participants were asked to groom themselves the same way for each photo session, with no makeup and their hair loose and combed back. They were also asked to make relaxed, neutral expressions in each photograph.

The photos were then shown to 65 observers, who did not know how much sleep the people in the pictures had gotten the night before. The observers rated the sleep-deprived people as 6 percent less healthy, 4 percent less attractive and 19 percent more tired-looking on average than the photographs taken when they were well-rested.

"The study suggests that your sleep, and how you sleep, affects how other people perceive you, and probably how they treat you," Axelsson told MyHealthNewsDaily. "Sleep is the best beauty treatment that we have."