“Screen time” used to mean sitting around and watching TV. For kids, too much time in front of the TV is linked to obesity, as well as trouble in school. But screen time doesn’t refer just to television anymore. Smartphones, tablets, and other handheld devices are now everywhere.

These new screens pose new challenges for parents, says Dr. Jenny Radesky, a pediatrician at the University of Michigan. “There’s so much content available now on something a child can carry from room to room,” she explains.

Almost all this new technology was designed for adults, not children, Radesky says. For example, a recent study by her team analyzed ads on YouTube channels marketed to kids. They found that more than half featured some age inappropriate ads, such as those for violent video games.

Parents may find it hard to know how much time their kids really spend on handheld devices. Another study from Radesky’s team found that young children who had their own tablets used them almost two hours a day. But only about a third of their parents accurately guessed that amount.

Researchers are exploring how this type of media use affects kids’ developing brains. They’re interested in whether the use of phones and tablets alters the brain’s executive functioning, Radesky explains. That’s the ability to focus on important tasks, resist distractions, and use self-control.

“Devices like tablets give you lots of stuff that’s really exciting, all at once, with no waiting,” Radesky says. Researchers want to know: Does that get in the way of kids doing harder tasks that help them build life skills?

Studies have already shown that too much media use can affect other aspects of kids’ health, including mental health and physical activity.

“And sleep is a major one,” adds Radesky. “A lot of studies have shown that the more kids use media, especially around bedtime, the worse their sleep is.”

But some uses of handheld devices can have benefits. Kids can use video chat to talk with relatives who live far away. Some educational apps and programs designed especially for children can help them in school. So how can parents find a balance?

“There are ways to set some limits about how much time they can spend on devices,” Radesky says. You can set timers. Some apps let you stop content from continuing to play automatically. For more tips on limiting screen time, see the Wise Choices box.

It can be hard for parents to track what their children are doing on portable screens. But adults can model thinking critically about what they see when watching TV or other media with their kids. You can talk about what you like and don’t like about a show or ad. You can point out when and why you think something is false or misleading. This can help kids learn these skills and use them on their own.

“From an early age, make it a norm that you can talk about what’s on devices,” says Radesky. “You want kids to come to you if they see something creepy, or if they’re just confused, because they know you can help them understand it.”

Setting Screen Time Boundaries

• Set a good example. Be a role model and limit your own screen time.
• Create a house rule that limits screen time and enforce it.
• Don’t allow screens during meals or homework.
• Give your kids alternatives to screen time. Suggest playing outside, finding a new hobby, or learning a sport.
• Do other activities together, such as family board games, puzzles, or going for a walk.
• Don’t put a TV or computer in your child’s bedroom or let them go to bed with a portable device.

Researchers are releasing data from the 10-year study each year so scientists can analyze it as the project progresses.

What does the early data from roughly 4,500 participants say so far?

Social screen time

Basically, there's good news and worrisome news, says Martin Paulus, M.D.

The good news: More social media use seems to be associated with some positive effects among 9- to 10-year-olds.

"We can't just say all screen time is bad."

- Martin Paulus, M.D.

The youngsters who spent more time texting or video chatting with friends than playing video games or scrolling the internet were more engaged with family and community.

They were also more involved in sports and other physical activities and had less family conflict.

"We can't just say all screen time is bad," says Dr. Paulus. "At least at this age, those engaged in more social media may be ahead of the curve to some degree, doing a little better, with fewer outside problems."

Screen time and aggressive behavior

The bad news: More video games and traditional types of screen time—like watching TV—were linked to more aggressive behavior in some children. Specifically, this behavior was found in those whose brain scans showed a less developed frontal lobe.

The frontal lobe is the part of our brains that controls how we express ourselves, problem solve, and communicate. Less developed frontal lobes are linked to aggression and bullying, Dr. Paulus explains.

These children also reported more sleep problems and higher family conflict.

However, Dr. Paulus cautions that we can't assume one thing caused the other. The data simply reports links and does not prove that the screen time causes bad outcomes.

Advice for parents

"What I would say to parents is that if their children are spending a lot of screen time at home and teachers or others are reporting problems with disruptive behavior at school, then it might be time to think about what else they can do," he notes. "Maybe more physical activity, or music or art."

So is screen time bad for kids across the board? Based on the data so far, no.

"Screen media use is not uniformly bad for the brain or the child," Dr. Paulus says. Of course, there's still more data and more research to come—nearly nine years of it.

Here's a surefire conversation starter: Tell a group of parents that you're studying whether too much screen time affects the brain development of children.

Then stand back and wait for the avalanche of questions.

"I can't tell you how many times I'm asked if too much screen time is bad or how to set limits. The most frustrating part is, everyone wants an answer and I don't have one yet," says Gaya Dowling, Ph.D.

But some answers may be coming soon.

Researchers are asking kids exactly how they use their screen time—multiplayer video games, solo games, or social networking, for example.

The ABCD Study

Dr. Dowling is the director of NIH's landmark 10-year study looking at how environmental, social, genetic, and other factors may affect a child's brain and cognitive development and influence their life. One of the components of this study is the effect of screen time on brain development and health from age 9 into young adulthood.

The ABCD (Adolescent Brain Cognitive Development) study is the largest long-term investigation into, among many other things, how scrolling, texting, game-playing, and other screen time affects kids' behavioral development and mental health.

It's led by the National Institute on Drug Abuse and the National Institute on Alcohol Abuse and Alcoholism and supported by eight other NIH institutes.

The study started enrolling participants in 2016 and is tracking nearly 12,000 children at 21 research sites across the country.

The project is particularly significant because, as one researcher explained it, "these kids are really the first of the screen time generation. Their births were announced on social media. Their first memories of screens were in the home. They're fully digitally immersed."

Tracking brain development

The youngsters will undergo MRI scans every two years to track their brain development and will have yearly questionnaires and interviews. This will track how factors like technology use impact their mental health and success in school.

"We're asking about things like substance use, sports and arts participation, depression, family conflict, and sleep problems," Dr. Dowling says.

Researchers are asking kids exactly how they use their screen time—multiplayer video games, solo games, or social networking, for example. This will help the researchers determine if some types of digital media are better than others.

At the moment, the data on how much screen time kids get is based on what they and their parents tell researchers.

But, as Martin Paulus, M.D., points out, "there's almost no correlation between what parents report about kids' screen use and what the kids report." Dr. Paulus is studying initial screen time data from the ABCD study.

Researchers are hoping, with permission from the kids and their parents, to log screen time automatically on smartphones and other devices.

Looking ahead

Will this bring us closer to knowing if too much screen time is bad for kids?

"I do think the longitudinal aspect of ABCD will help us make more reasonable recommendations," says Dr. Paulus, but much depends on what the study finds over the long run.

After all, the way kids use screen time when they're 9 or 10 may change when they hit puberty. And every child is different.

"Some kids say it's easy for them to spend a couple of hours on their phone and then go do something else, while others see it as an escape and feel bad or get angry if they're not spending that screen time," he says.

The findings will likely interest many parents.

That includes Dr. Dowling herself, who admits she's struggling to set reasonable screen limits for her 12-year-old daughter and 13-year-old son.

"They often spend time on their digital devices when I would rather they were doing other things," she adds.

Feel like your screen time may be eating into family time? Here are tips for setting screen time limits.

Make family time a no-screen time

Mealtime and family gatherings should be screen-free. Gaya Dowling, Ph.D., NIH's director of the Adolescent Brain Cognitive Development study, says her kids might be glued to their phones at other times, but not at dinner. A no-screens-at-meals rule encourages everyone to make eye contact—instead of looking down at their phone—and to actually talk to each other.

Keep the bedroom screen-free

Don't put a TV or computer in your child's bedroom—it can disrupt sleep, increase screen usage, and isolate kids from the rest of the family.

Set a good example

Parents should be a good role model and set limits on their own screen time. "Parental screen usage is a factor that comes up a lot" when looking at the effects of children's screen use, says ABCD researcher Florence Breslin.

Get kids involved in other activities

"Emphasize physical activity. It's extremely helpful and preventive for mental health problems," says Martin Paulus, M.D., who oversees the ABCD study at the Laureate Institute for Brain Research in Tulsa, Oklahoma. The study is also looking at the effects of music and arts participation.

For many of us, limiting our computer use and getting away from all screens can be a challenge. "Screen time" means television screens, computer monitors, and even the handheld devices we use for checking email, listening to music, watching TV, and playing video games on the go.

Health experts say screen time at home should be limited to two hours or less a day. The time we spend in front of the screen, unless it's work- or homework-related, could be better spent being more physically active (increasing our energy out).

As a parent or caregiver, you can set a good example for your kids and set rules that limit their computer time, TV watching, and video game playing to reduce how much time they spend in front of a screen. Research by the Henry J. Kaiser Foundation shows that setting rules about media use is hard for many parents.

In 8- to 18-year-olds:

• 28% said their parents set TV-watching rules
• 30% said their parents set rules about video game use
• 36% said their parents set rules about computer use

However, the same study also showed that when parents set any media rules, children's media use is almost three hours lower per day.

Talk to Your Family

Explain to your kids that it's important to sit less and move more in order to stay at a healthy weight. Tell them they’ll also have more energy, and it will help them develop and/or perfect new skills, such as riding a bike or shooting hoops, that could lead to more fun with friends. Tell them you’ll do the same.

Set a Good Example

You need to be a good role model and limit your screen time to no more than two hours per day, too. If your kids see you following your own rules, then they’ll be more likely to do the same.

Log Screen Time vs. Active Time

Start tracking how much time your family spends in front of a screen, including things like TV- and DVD-watching, playing video games, and using the computer for something other than school or work. Then take a look at how much physical activity they get. That way you’ll get a sense of what changes need to be made.

Make Screen Time = Active Time

When you do spend time in front of the screen, do something active. Stretch, do yoga and/or lift weights. Or, challenge the family to see who can do the most push-ups, jumping jacks, or leg lifts during TV commercial breaks.

Set Screen Time Limits

Create a house rule that limits screen time to two hours every day. More importantly, enforce the rule.

Create Screen-free Bedrooms

Don’t put a TV or computer in your child's bedroom. Kids who have TVs in their room tend to watch about 1.5 hours more TV a day than those that don’t. Plus, it keeps them in their room instead of spending time with the rest of the family.

Make Meal Time = Family Time

Turn off the TV during meals. Better yet, remove the TV from the eating area if you have one there. Family meals are a good time to talk to each other. Research shows that families who eat together tend to eat more nutritious meals. Make eating together a priority and schedule family meals at least two to three times a week.

Provide Other Options

Watching TV can become a habit, making it easy to forget what else is out there. Give your kids ideas and/or alternatives, such as playing outside, getting a new hobby, or learning a sport.

Don't Use TV Time as Reward or Punishment

Practices like this make TV seem even more important to children.

Understand TV Ads & Placements

Seeing snack foods, candy, soda, and fast food on television affects all of us, especially kids. Help your child understand that because it’s on TV—or your favorite TV characters/actors eat or drink it—doesn’t mean a food or drink is good for you. Get your kids to think about why their favorite cartoon character is trying to get them to eat a certain brand of breakfast cereal.

According to the Kaiser Family Foundation, kids ages 8-18 now spend, on average, a whopping 7.5 hours in front of a screen for entertainment each day, 4.5 of which are spent watching TV. Over a year, that adds up to 114 full days watching a screen for fun. That’s just the time they spend in front of a screen for entertainment. It doesn’t include the time they spend on the computer at school for educational purposes or at home for homework.

The CDC recommends kids get at least 60 minutes of physical activity each day. The time kids spend watching TV, playing video games, surfing the web, is time they could be physically active.

As a parent or caregiver, you play a big part in shaping children's eating and drinking habits. When you make it a habit to consume foods and beverages that are low in added sugars, saturated fat, and salt and are high in fiber, the children you care for may learn to like these foods as well. If a child you are caring for does not like a new food right away, don't be upset. Children often need to see a new food many times before they will try it.

Be a role model. As a parent or caregiver, you also have an effect on children's physical activity. You do not need to be an expert at any activity. Just get up, move, and show children how much fun being active can be. They may grow to like it too. You can set a good example by going for a walk or riding a bike instead of watching TV, playing a video game, or surfing the internet. Find an activity that you enjoy and can do together.

Talk about being healthy. As you learn more about how to improve your health, take the time to talk to your children about how a certain food or physical activity may help them. For example, when going for a walk, bring your children with you and let them pick the route. Discuss how walking helps you feel better and is a fun way to spend time together.

Use your children's food and beverage choices as teaching moments. Speak up when you see unhealthy choices. Direct children to healthier options or say, "You can have a little of that, but not too much." Talk to them about why an overly salty or heavily sugared snack is not the best choice. Avoid making them feel guilty about their food or beverage choices. You can also praise your children when they choose a healthy item like fruit.

Use comments like these

• "Great choice!"
• "You're giving your body what it needs with that snack!"
• "I like those, too."

With physical activity, try upbeat phrases like these to keep your child excited

• "You run so fast, I can hardly keep up!"
• "You are building a strong, healthy heart!"
• "Let's walk 10 more minutes to make us stronger."

Make sure your child gets enough sleep. Getting enough sleep can improve your child’s mental, emotional, and physical health. Not getting enough sleep may lead to many health issues, including obesity. Find out how many sleep hours experts recommend for your child, depending on his or her age.

Believe in the power to change. Know that eating healthy and moving more are the building blocks to better health. Work together to form healthy habits.

Promote good health beyond your family. Other adults may play a role in your child's life, too. You can share ideas about healthy habits with them. For instance, many parents and caregivers work outside the home and need others to help with childcare. Family members, day care providers, babysitters, or friends may shape your child's health habits. Talk to them to make sure they offer healthy meals, snacks, and drinks. Check that caregivers are also providing plenty of active playtime and limiting inactive time spent with TV, video games, or other devices.

If your child is in school, you can help promote healthy habits in several other ways

• Find out more about the school's breakfast and lunch programs.
• Find out about the school’s physical education program, and look for opportunities to be active during the school day.

Consider other influences. Just as they do for you, your children's friends and the media can also affect healthy choices.

Some TV, online, and other ads try to persuade children to consume high-fat foods and sugary drinks. You can help your children be aware of these pressures. Speak with your children about choices while you watch TV, surf the internet, or go to the movies with them. Talk about how media outlets and influencers sell products or convey values through famous athletes, child celebrities, cartoon and action figures, and made-up images. Use programs and ads to spark chats about your values. These talks may help your child make healthy choices outside the home.