Why You Shouldn’t Check Your Smartphone Before Going to Bed

If you feel lost at night without your phone, you’re not alone. More than 90 percent of American adults own a cellphone, and 44 percent take it to bed with them, one study found. But those late-night texts and calls could be disrupting your nightly appointment with the sandman.

A growing body of research indicates that exposure to the blue light that glows from your smartphone and other electronics, such as computers and tablets, might be keeping you awake at night.

A key factor, scientists say, is that the LED light emitted by digital screens may prevent your brain from releasing the hormone melatonin, which tells the body when it’s time for bed and controls sleep and wake cycles. The result: “Sleep problems are becoming increasingly common,” according to Liese Exelmans, coauthor of a Belgian study showing that those who use smartphones or other media before going to bed had poorer sleep quality, shorter sleep duration, and more daytime fatigue.

What’s worrisome, Exelmans noted, is how these sleep problems can affect driving. She cites numbers from the Centers for Disease Control and Prevention showing that 5 percent of people reported nodding off or falling asleep while driving in the preceding 30 days.

Her advice: Don’t take your devices into your bedroom. And if you just can’t do that, dim the light on your phone and put it into airplane mode. If you use it as an alarm clock, try switching to a non-digital clock instead.