Advice on sleep for kids is mixed

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Updated: February 13, 2012 8:04PM

For a century, experts have been saying kids don’t get enough sleep, partly because the blinking lights of technology keep them up. But there’s no hard evidence for these claims, according to a study Monday in the journal Pediatrics.

In fact, researchers at the University of South Australia found that, between 1897 and 2009, children’s daily sleep decreased about 75 minutes, while the recommendations for how much sleep children should get declined by 70 minutes.

As the numbers keep pace, “experts have always recommended that children get about 40 minutes more sleep than they do, no matter how much sleep they get,” says researcher Timothy Olds, whose new report also finds a common belief over the years that children are overtaxed “by the stimulation of modern living.”

In the early 1900s, artificial lighting, radio and the cinema were cited for delayed bedtimes. By the 1990s, video games, the Internet and mobile phones were blamed.

When it comes to prescribing sleep, most recommendations “are guesses,” says study co-author Lisa Anne Matricciani.

The key to knowing if a child has adequate sleep is whether the child “wakes up refreshed in the morning,” says Stanford University Medical Schoo sleep specialist Rafael Pelayo.