People, don't do this. Four good reasons:
1. You could catch your linens on fire. Cell phones have been known to melt or otherwise catch on fire because of a faulty battery. They can also overheat if left in a functional mode. This is advice from the category of Good Common Sense: if you need to have your cell phone nearby, then at least put it on a firm surface. Read more: "What's causing your cellphone to get so hot?"
2. It might be even Better Common Sense to not have your phone in the same room with you at all while you sleep. Why? Every time you get a text or a call, even if the sound is turned off, the screen flashes on, and in doing so, it emits blue spectrum light. Your body can still perceive blue spectrum light even if your eyes are shut, due to photoreceptor cells that are contained in your skin. Blue spectrum light has been shown to delay or block the production of the sleep-promoting hormone, melatonin, in the pineal gland. If your body is not getting adequate melatonin, it cannot effectively achieve sleep onset. So... perhaps turning the phone off entirely would make more sense, or at least turning it face down with the sound off would be the alternative if you just couldn't stand to not have your phone with you. Learn more: The melanocyte photosensory system in the human skin.
3. Though the jury is still out on this point, you might consider the fact that cellphones to emit a small amount of electromagnetic radiation (EMR). Sleeping with a constant stream of EMR emissions next to your head or even next to your bed may be yet one more reason to not have your phone in the same room with you at all while you sleep. Check out this detailed discussion at the David Suzuki Foundation, which does not take a position on the debate surrounding EMR and cell phone use.
4. Finally, having a cell phone in bed with your, or even next to you, means you are more likely to answer it, no? You are woken up by a text or a call... how much self control do you have? If you receive important calls at night because you are on call or in management or for some other legitimate reason, that's one thing. Using your cell phone as an alarm is common and, probably, harmless if you keep your phone plugged in away from your head. But we have seen patients in the sleep lab who are just having conversations with people in different time zones at that time. Patients who are taking calls from people who have no business calling at that time of night (meaning: people who are practicing very poor sleep hygiene and have no respect for other people's lifestyles). Patients who reach for their phones to check the time in the middle of the night, though there is no healthy reason to check the time in the middle of the night (it will not make you go back to sleep more easily, that's a guarantee!) Or patients who, because they can't sleep (see number 2), turn on their phones to find something to pass the time, which further interrupts melatonin production and more grossly enhances their sleeplessness. Are you worried you might have a cell phone addiction? Check out these various entries on cell phone overuse at Huffington Post.
Bedtime is supposed to be about sleep. If you are struggling to get sufficient sleep and keep your phone at your bed because you can't resist checking out the latest Pinterest link your friend has just texted you or playing your round of a smartphone game app as soon as your opponent's notification arrives--even if it's at 2am--then you need to be thinking about what your priorities are. You cannot live well with insufficient sleep. Insufficient sleep causes car accidents, loss of sex drive, impaired judgment, reduced performance on the job, increased risk for disease (especially cardiovascular, but stroke and diabetes, as well), accelerated aging of the skin, weight gain, memory loss, cognitive deficits, and depression. It's up to you to decide if that Pinterest link arriving at 2am is worth breaking a healthy cycle of sleep for, but we suspect that you will ultimately decide it's not.
