Good night, sleep tight, and don't look into that tablet light.
Dads and moms who are concerned about the quantity and quality of their children's sleep should keep mobile devices like phones, tablets and laptops out of kids' bedrooms, according to a new study published Monday in JAMA Pediatrics.
It's no surprise that using a mobile device before bedtime is associated with trouble falling asleep and staying asleep, as well as more daytime sleepiness. Most of us know that the light from tablets and phones can mess with circadian rhythms, making it harder for us and our kids to get a good night's sleep, for example.
But the authors also report that simply having access to a device in the bedroom — even if it is not used before bed — is associated with increased odds of poor sleep length and quality for kids.
"Sleep is an often undervalued but important part of children's development, with a regular lack of sleep causing a variety of health problems," study leader Ben Carter from King's College London said in a statement. "With the ever growing popularity of portable media devices and their use in schools as a replacement for textbooks, the problem of poor sleep among children is likely to get worse."
Already, the researchers report, 72% of all kids and 89% of adolescents have at least one mobile device in the bedroom, and most of them regularly use it before bedtime.
For kids, a good night's sleep is defined as falling asleep relatively easily, staying asleep throughout the night, and only waking up after nine or 10 hours of rest.
Keeping mobile devices out of a kid's room is no guarantee that children will have a perfect night of sleep, but it can certainly boost the odds of it happening, the authors found in a meta-analysis of 11 different studies that looked at the relationship between kids and mobile devices.
For example, the researchers found that 31.5% of kids who do not have mobile devices in their room reported that they don't get enough hours of sleep a night, compared with 41% of kids who have access to a device and 45.4% who use their devices just before bed.
They saw a similar pattern for sleep quality, or how hard it is for kids to fall asleep and stay asleep. About 34% of kids with no access to mobile devices at bedtime reported poor sleep quality, compared with 44% of kids who had a device in the sleep environment and 52% of kids who used a device before going to bed.
Kids with no devices in their room also reported less daytime sleepiness than their peers who kept devices in the bedroom.
Although this particular study does not examine why devices interfere with sleep quantity and quality, the authors say it is probably a combination of factors.
They note that digital content can be psychologically stimulating and that light emitted from devices affects circadian timing, making it difficult to fall asleep. As for the effect on sleep of having a device in the room and not using it, experts say that may be due to the "always on" nature of social media.
Although more work needs to be done to learn exactly how mobile device use can affect sleep, the authors say that the take-away for parents is to get those devices out of the bedroom, at least during sleeping hours.
"It is imperative that teachers, healthcare professionals, parents, and children are educated about the damaging influence of device-use on sleep," they wrote.
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