It is a common complaint of our modern age that kids and teens don’t get enough sleep.

Video games, TV, social media, and other trappings of our increasingly tech-centric lives are often blamed, but a new study shows that long before Facebook or PlayStation 3, kids were sleeping less than experts said they should.

When researchers in Australia reviewed sleep recommendations and actual sleep times among children over the past century, they found that kids consistently slept about 37 minutes less than recommended at the time.

Each time, new technological marvels -- be it the light bulb in the early 1900s, TV in the 1950s, or computer gaming systems and social networking today -- were blamed for declining sleep times.

“The message that children don’t get enough sleep has been the same for over 100 years,” says researcher Tim S. Olds, PhD, of the University of South Australia.

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Sleep Recommendations Not Scientific

Olds says health policymakers have been making recommendations about how much sleep children should get each night for more than a century, with very little scientific evidence to back the recommendations up.

That is because studying optimal sleep times during childhood is very difficult.

Getting too little sleep has been linked to an increased risk for obesity, poor school performance, behavioral problems, and substance abuse.

But like adults, individual children and teens appear to have different sleep needs, Olds says.

When they explored sleep recommendations over the last century, Olds and colleague Lisa Anne Matricciani found 32 sets of age-specific sleep recommendations since the late 1800s and about 200 studies examining actual sleep times among children and teens.

On average, age-specific sleep recommendations declined by about 0.71 minutes per year between 1897 and 2009, and this paralleled a similar decline in sleep times.

Actual sleep times were consistently 37 minutes less than recommended over the observation period.

The study appears online today and in the March issue of the journal Pediatrics.

“The rationale for sleep recommendations was also strikingly consistent for more than 100 years: Children were overtaxed by the stimulation of modern living, although that stimulation was embodied in whatever the technological avatar of the time was,” the researchers write.

Some Kids Need More Sleep, Some Need Less

According to the National Sleep Foundation, school-aged children who are 12 and under need at least 10 to 11 hours of sleep each night, while teenagers need eight-and-a-half to nine-and-a-half hours of sleep.

Olds says parents should not be too concerned if their children or teens get a little more or a little less sleep each night, as long as they seem to be functioning well at home and school.

Pediatric sleep specialist William Kohler, MD, agrees.

Kohler is medical director of the Florida Sleep Institute at Florida Hospital in Tampa.

“A child who is alert and doing well in school with no behavioral issues is probably getting enough sleep,” he says.

But he adds that when there are issues, poor sleep quantity or quality should be one of the first suspects.

“We may not have good standards for understanding how much sleep an individual child needs, but there is plenty of good evidence that getting too little sleep or having poor-quality sleep leads to a wide range of health and behavioral problems,” he tells WebMD.