Sleep researchers have advised people to keep their smartphones far away from their bed, as they have led to a rise in sleep-related problems.
Sure, you can flip your phone to quiet mode. But the draw to roam in the early hours is powerful. Sleep researchers say this isn't good for you. You might as well get up and drink a shot of espresso.
David M. Claman, director of the Sleep Disorders Centre at the University of California San Francisco Medical Centre, has said that it's a very slippery slope, as once you've picked up your phone to see what time it is, it leads to checking your email and to lying awake with anxiety.
He said that when one wakes up in the middle of the night and checks his phone, he will inevitably get frustrated and worried by something he has seen, leading the body to tense up.
Then you find yourself tossing and turning, thinking about an email, a text or a meeting in six hours.
Claman said smartphones in the bedroom had led to a rise in sleep-related complaints from his patients.
He said that for people in their 20s and 30s, the phone is becoming a more common contributing factor to insomnia, the Sydney Morning Herald reported.
Sleep researchers say that looking at a blue light, which is produced by smartphone and tablet screens, sets off brain receptors that are intended to keep us awake and interferes with circadian sleep patterns.
Experimental research has found that if people use a tablet for up to two hours before bed, it takes an extra hour to fall asleep.
Orfeu M. Buxton, a neuroscientist and assistant professor in the division of sleep medicine at Harvard Medical School, said the phone in the bedroom could set off what he called "threat vigilance", which is a type of anxiety that keeps you awake.