Dr. Robert Karman, MD, addresses three common beliefs about catching z's.

Woman in Sleep Mask
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It Is More Than a Passive Time of Rest

"Sleep is an active process that anchors many physiological processes," says Dr. Karman of Expert Sleep Medicine in Louisville, Kentucky. During deep sleep, your brain further ingrains memories; reinforces learning; and clears out a waste protein that, if built up over time, can be a risk factor for dementia. A lack of rest also alters your metabolism and can cause you to gain weight.

Playing Catch-up On Weekends is Not in the Cards

The current recommendation for adults is seven hours of shut-eye, notes Dr. Karman, but many people don't get that much. "Sleeping in on the weekends can often make us feel better, but it doesn't undo the harm of too little rest during the week," he says. "You can't pay back the sleep debt's effects on your metabolism [and other physiological processes]."

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Beauty Sleep is a Real Thing

Sort of. "You'll age more gracefully, live longer, and have a better quality of life if you get better sleep," says Dr. Karman. It can also minimize risk factors that are associated with strokes.

Dream On

Skip the sheep. Turn to these dreamy finds for a good night's sleep.

Best Items for A Good Nights Sleep
Credit: Hector Manuel Sanchez; Styling: Mary Beth Wetzel

Now that you've learned a few things about sleep, it's time to relax and get some well deserved sleep.