NEW YORK — More teens than ever before aren’t getting a sufficient amount of sleep, and too much screen time — particularly from smartphones — is likely to blame, a new study finds.

Researchers at San Diego State University and Iowa State University looked at data from two large, nationally-representative studies covering more than 360,000 American teenagers, finding that a significant number of millennials are sleep deprived.

Person sleeping in bed
A new study finds that more teens than ever before are getting an insufficient amount of sleep, and smartphone use is believed the culprit.

One study examined, called the Monitoring the Future survey, helped the researchers calculate the percentage of children who average less than seven hours of shut-eye a night, while the other— referred to as the Young Risk Behavior Surveillance System survey— helped them evaluate the average number of hours of sleep an adolescent got on a school night.

On both metrics, today’s youth are lacking sufficient slumber, the researchers found.

In 2015, nearly 40 percent of adolescents got less than seven hours of sleep a night on average, which represented a 17 percent jump from just six years prior, and a 58 percent increase from a 1991 study.

This shift in sleeping habits was likely directly attributable to increased internet use, as supported by one statistic: teens who used the web for at least five hours a day were 50 percent more likely to get insufficient sleep than peers who only spent an hour online a day.

Lead researcher Jean Twenge points out that smartphone adoption reached critical mass around 2009, which may explain why trends have developed as they have.

“Teens’ sleep began to shorten just as the majority started using smartphones,” says Twenge in a university news release. “It’s a very suspicious pattern.”

Sleep deprivation is a very serious issue, Twenge warns, as it causes many youth to be inattentive in class, and drowsy during other activities.

“Our body is going to try to meet its sleep needs, which means sleep is going to interfere or shove its nose in other spheres of our lives,” explains Twenge, who has authored books on millennials. “Teens may catch up with naps on the weekend or they may start falling asleep at school.”

While technology can play a beneficial role in an adolescent’s life, it can become detrimental past a couple of hours of use a day, Twenge notes.

She particularly recommends that teens eschew their phones and tablets before bed, as the devices can interfere with restful sleep.

The full study was published last month in the journal Sleep Medicine.

About Daniel Steingold

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  1. Dr.Tickles says:

    That is because a majority of them become so traumatized throughout the day from being offended by viewpoints or opinions that differ from theirs that their brain just can’t handle the stress.