Kids need sleep: Study shows the difference a half-hour makes

A little bit of sleep goes a long way. 

That’s the message from a new study published this week in the journal “Pediatrics,” in which researchers found that even a small increase or decrease in shut-eye can have a major impact on the behavior of otherwise healthy children in elementary school. 

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In this study, 34 children ages 7 to 11 were divided into two groups: one whose parents put them to bed an hour later than normal, the other whose parents turned off the lights an hour earlier. The researchers monitored the children’s sleep, to make sure they were actually snoozing because of the early bedtimes. Then, the students’ teachers – who did not know whether their pupils were getting more or less sleep – evaluated the children’s behavior over the course of a week.

The results were clear: A cumulative extension of sleep duration of about 27 minutes meant detectable improvement in behavior, while a cumulative restriction of sleep of about 54 minutes led to a deterioration in children’s restless-impulsive behavior and general emotional wellbeing, as determined by their teachers.

Simply put, the kids who slept less were grumpy. 

(I’m sympathetic.)

This is not the first study to show the importance of sleep for children. A study of high school students in the 1990s, for instance, showed that those teens who slept an average of 25 more minutes a night got better grades than their night owl peers. 

But what’s telling about this new research is the short amount of time – only five days – that it took for teachers to notice a significant difference in children’s behavior. Additionally, the child participants in the study did not have any prior sleep problems, and regularly slept at least 8.5 to 9.5 hours a night. 

It doesn’t take much, the data shows, for sleep – or lack thereof – to have an impact.

“Given the positive impact of moderate sleep extension and the negative impact of moderate sleep restriction, it is important that parents, educators and student are provided with sleep education featuring data on the critical impact of sleep on daytime function,” the researchers wrote. “Sleep must be prioritized, and sleep problems must be eliminated.”

Easier said than done, some parents say. Sleep is one of the major battle grounds for parents and their kids; check out our earlier post about new research on the controversial "cry it out" method.