Yes, we all know we should put our phones down, turn the TV off and go to bed. But there’s always another episode to watch on Netflix or a Facebook post we don’t want to miss.

In our quest to live healthy, we focus on good nutrition and exercise. Yet sleep is also vital for both our physical and mental health, says Dr. Teresa Aoki, a sleep expert and associate professor of family and internal medicine at Des Moines University.

“The problem with sleep is that we take it for granted,” Aoki says. “We are in this busy schedule. Everybody is. And there are things that should have been done yesterday. Then the only time we get to sleep, we start stealing from our sleep time. It is a widespread problem, actually, inadequate sleep time.”

The U.S. Centers ...