Three Ways TV Keeps Kids Up — and Maybe Adds Pounds

From TV to video games and smartphones to tablets, screens are the best worst thing to happen to parenting. They’re great learning tools and often lifesavers for younger kids, but many of us may worry about how much our kids use them — and what the effects of too much use might be. Unfortunately, sleep is one of those areas that can particularly suffer if parents aren’t vigilant about regulating kids’ screen use before bed.

Up to 90 percent of Americans use some type of electronic device within an hour before bed a couple times a week — and that behavior starts young.

When researchers looked at 67 different studies on media and sleep, 90 percent of them showed more screen time meant less sleep. Parents know the misery of dealing with a kid who hasn’t had enough sleep, but that’s just the beginning.

“Children with reduced sleep will suffer from decreased ability to concentrate, to form memories and learn effectively, making it difficult for them to achieve their full academic potential,” says Dr. Mark Joseph Buchfuhrer, medical director of the Comprehensive Sleep Center at Good Samaritan Hospital in Los Angeles.

Research also shows too little sleep leads to more weight gain. Kids may be too tired to get enough physical activity or they may eat while watching TV. Additionally, insufficient sleep could disrupt metabolism.

“Parents should always monitor the amount of time a child is using a screen, especially with watching television or playing video games prior to bedtime,” says Dr. Danelle Fisher, chair of pediatrics at Providence Saint John’s Health Center in Santa Monica, Calif. “Reduced sleep quality and quantity can affect growth and well-being.”

TVs, smartphones, tablets and other screens can hurt kids’ sleep in at least three ways.

1. More screen time means less sleep time.
Kids often stay up watching TV or playing games instead of sleeping. “Sitting with a media screen is very compelling and will take time away from sleep as children will try to postpone bedtime,” Buchfuhrer says. One study of more than 2,000 fourth and seventh graders found kids got 20 fewer minutes of sleep when they slept near small screens like smartphones. They were also almost 40 percent more likely to say they didn’t feel well rested. Kids with TVs in their rooms got 18 fewer minutes of sleep.

2. Light from electronic devices affects sleep hormones.
The hormone melatonin regulates the human body’s circadian rhythm, or internal clock. The body releases melatonin at night and suppresses it with the morning light. But it’s not just sunlight that influences melatonin’s release. Almost all screens emit short-wavelength “blue light.” Research suggests this blue light also suppresses melatonin, disrupting kids’ internal clocks.

In one study, adults using e-readers before bed felt less sleepy at bedtime, took longer to fall asleep and felt less alert the next morning compared to those reading paper books. Their bodies also secreted less melatonin, shifting their internal clock later. Kids aren’t immune to these effects. Their developing bodies may even be more susceptible to it.

3. Electronics are stimulating.
Ever had trouble falling asleep after watching a horror flick or action film? Kids minds race just like yours after watching or playing something exciting.

“We know that screen time before bed is a stimulant and can interfere with the ability to fall asleep and may also impact how restful sleep is,” Fisher says. Kids can’t switch off that buzz any more than you can.

“TV and computer games make it more difficult for children to wind down,” Dr. Buchfuhrer says.

Screens and sleep can become a vicious cycle too. “Lack of sleep promotes daytime fatigue, which may make it difficult for children to engage in physical activities and thus further induce them to participate in sedentary activities, such as watching TV and computer/tablet games,” Dr. Buchfuhrer says. “Promoting better and longer sleep should result in healthier, happier children who will do better in school, behave better and have less risk for obesity, diabetes and heart disease.”