This little luxury can lead to poorer grades, bigger waistlines, and more aggressive behavior.

By Amanda MacMillan
Updated September 27, 2017
Mark Bowden/Getty Images

Children with television in their bedrooms spend less time reading and sleeping, according to new research—and within months, are also more likely to perform poorly in school, gain excess weight, or develop video-game addictions. Although child development experts have long suspected that TV in the bedroom might have consequences like these, this is one of the first studies to track its effects over time.

The study, published in Developmental Psychology, followed more than 4,700 kids in the United States and Singapore, ages 6 to 17, for at least six months and up to two years. Overall, it found that kids who had bedroom access to media (defined as television and/or video games) spent more total time in front of a screen—which was subsequently associated with poorer grades in school, higher body mass index, physical aggression, and symptoms of video-game addiction.

The researchers found a few possible explanations for this “ripple effect” among their data: For starters, more screen time meant less time spent reading, sleeping, and engaging in other types of active play.

“This study shows that bedroom media have effects not just because of what children watch or play, but because of what they don’t do instead,” says lead author Douglas Gentile, PhD, professor of psychology at Iowa State University.

Children with TVs or video games in their rooms also tended to watch programs and play games that are more violent than they normally would elsewhere in the house—which could explain the rise in aggressive behavior, the authors say.

“When most children turn on the TV alone in their bedroom, they’re probably not watching educational shows or playing educational games,” says Gentile. “Putting a TV in the bedroom gives children 24-hour access and privatizes it in a sense, so as a parent you monitor less and control their use of it less.”

Gentile says that children today spend close to 60 hours a week in front of screens, a number that continues to trend upward. More than 40 percent of 4- to 6-year-olds have a television in their bedroom, according to national studies, as do the majority of kids 8 and older.

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The study was not able to show a cause-and-effect relationship between television in the bedroom and the various health and behavioral outcomes it measured, but the authors say it strongly suggests one. And although there are many things that can affect measures like school performance and body mass index, they did attempt to control for other factors such as age, gender, and socioeconomic status.

While this research only looked at televisions and video-game consoles, Gentile expects that tablets, smartphones, and digital handheld games are also likely having the same effects on kids—if not stronger, considering their widespread use and their always-connected nature. “It seems like parenting just keeps getting a little harder,” he says.

The study authors recommend parents stand firm about making sure digital devices aren’t used behind closed doors—or at least taking them out of the bedroom at night to charge, so kids aren’t using them all night long.

Gentile also believes it’s important to set rules about television when children are young—and to stick to them. “It’s a lot easier for parents to never allow a TV in the bedroom than it is to take it out,” he said. “It’s a question every parent must face, but there is a simple two-letter answer. That two-letter answer is tough, but it is worth it.”