When it comes to good sleep hygiene, limiting screen time is often at the top of the list. This applies to both adults and children, who routinely hear that the blue light behind laptops, cell phones, and tablets convince the brain to remain awake. According to researchers at Oxford University, there’s little evidence to show that daytime screen use prevents children from sleeping.
While this might sound like great news to iPhone-worshipping tweens, medical professionals are questioning the results already. With that in mind, it’s worth looking at what the study involved and how other evidence stacks up against it.
Why do we believe that screen time affects the way children sleep?
Sleep specialists around the world believe that too much screen time prevents children from sleeping. There are several reasons for this. The first relates to sleep hygiene: looking at backlit screens too close to bedtime. Similarly, having a backlit screen in a child’s bedroom can prove distracting, especially if they shun sleep in favor of using it.
The content children digest could also prevent sleep. As adults, we can use emotional and cognitive techniques to switch off before bedtime, even when we’ve just learned something exciting or worrying. To use recent events as an example, many adults who were either excited or worried by last night’s election as the polls closed could probably employ stress-reduction techniques to sleep better. Some of those techniques happen automatically, others require practice. Either way, kids don’t possess the same skills as adults and so they remain in a heightened state beyond bedtime.
Finally, there’s the blue light theory. As backlit screens are relatively new in the science world, this is a theory with only a little evidence behind it. It proposes that the blue light that comes from our screens disrupts our circadian rhythms, leaving our brains wondering whether it’s night or day. Once again, children have more sensitive circadian rhythms than adults. As such, there’s more scope for disruption.
What does the latest research into screen time suggest?
The study from Oxford looked at data from the U.S. Using surveys filled out by parents, those collecting the data assessed:
- How much screen time children were having. This includes video games, phones, TVs, and other such devices.
- How long children were sleeping for. Again, parents measured this.
One of the biggest issues with this type of study is reporting bias. People are more likely to participate in such surveys when they feel motivated to make a certain report. For example, surveys on hospitals might feature a lot of complaints, as people feel motivated to complain. Theoretically, parents might feel more motivated to report positive sleep patterns because they feel vindicated in honestly stating that their child sleeps well despite high screen time levels. This also means those who have seen poor sleep patterns might steer away from such surveys. Or, they could tweak the truth.
As the study focused on children between 6 months and 17 years, it’s also worth querying how accurate the honest reports were. While most parents will closely monitor their children’s sleep habits in the earlier years, this becomes more difficult as they grow independent. It’s unlikely that any teenager would want Mom or Dad watching for the moments they fall to sleep and wake up.
Admittedly, the sample size is very significant. It features 50,000 children from every state, which means it’s also highly representative of different demographics. The study found that children who overuse screens sleep for 7 hours and 21 minutes on average. Those who abstain sleep for 7 hours and 51 minutes on average.
What do these results mean?
In the context of different pediatric age groups, these results may not mean much. For example, toddlers should ideally get 11 to 14 hours per night. At a minimum, they need 9. In contrast, a teenager aged between 14 and 17 should grab between 8 and 10 hours per night. At a minimum, they need 7.
Essentially, anybody under the age of 14 who gets less than 8 hours per night may struggle to escape sleep deprivation. As multiple studies show, this can affect concentration, memory, and the development of socially appropriate emotional responses. In the infant to pre-teen age groups, the missing half-an-hour in heavy screen time users could have a significant impact.
So, while the research team at Oxford states that the effect of screen time is “extremely modest,” they may not be painting a full picture. For a true analysis, we’d need a longer study, with more reliable observations, and we’d need the differences between age groups to act as an influencing factor when interpreting the results.