Toddlers and young children who spend more than three hours viewing a screen, either watching TV or playing on a tablet, are more likely to be sedentary by the time they reach kindergarten-age, a new study found.
Researchers from the National University of Singapore suggest limiting the exposure of toddlers and young children to screens may result in healthier behaviors later in life.
The findings published Tuesday in the peer-reviewed journal Lancet Child & Adolescent Health , are based on monitoring the screen time of 500 toddlers and preschool-aged children in Singapore.
Parents were asked to report their children’s exposure to video games or shows on televisions, computers or handheld devices such as a laptops or tablets. At the age of five, the children were given an activity tracker, which monitored their physical activity, how much they were sedentary and their sleeping habits.
On average, researchers found children in the study spent 2.5 hours a day on screens, with television occupying the longest viewing time. A third of screen time was on handheld devices. Only a few children spent less than an hour in front of a screen.
Children who spent more than three hours in front of a screen spent a half-hour less doing light physical activity and 10 minutes less doing moderate to vigorous physical activity (MVPA).
Bozhi Chen, a researcher at the National University of Singapore who co-authored the study, said in a statement the research strengthens existing associations between screen time and children’s health.
“Our findings support public health efforts to reduce screen viewing time in young children and suggest further research into the long term effects of screen viewing on movement behaviors is needed,” she said.
Existing research also linked too much screen time with behavioral problems, inadequate sleep and obesity but mostly focused on teenagers and other school-aged children, the recent study noted.
Sarah Benjamin-Neelon, an associate professor of public health at Johns Hopkins University, said the long-term effects of screen time on toddlers and young children remain uncertain, but the study offers “some insight into possible negative effects.”
“The suggestion is that we as parents can improve our children’s health outcomes by reducing screen time when they are toddlers,” said Mayo Clinic’s Children Center pediatrician Kelsey Klaas, noting the study does not prove such outcomes. “Early childhood is a great time to establish healthy behaviors.”
The World Health Organization and the American Association of Pediatrics recommend young children and toddlers be allowed only an hour a day of screen time.
The best way for parents to cut back on screen time, Klaas suggested, is to be active with their children.
“As parents, we need to put down our own phones and other distractions, turn off the TV, and can also help by providing some ideas for games or activities,” Klaas, who is unaffiliated with the study, told USA TODAY. “To be physically active, some amount of open play space, whether indoors or out, is necessary.”
Despite possible cultural differences between Singapore and the United States, Klaas cited a similar study in the United States that found similar levels of screen time in American children.
Some experts pointed out the study did not make a clear causal link between screen time and physical activity.
Dorothea Dumuid, a researcher at the University of South Australia who also is not affiliated with the study, said in a statement screen time may be an indication of other factors not addressed in the study.
Benjamin-Neelon warned the study did not take into account how active kids were when they were toddlers.
“It is possible that children who watched more screens at that time were also already less active,” she said.
Child care is another unaddressed factor , Benjamin-Neelon said.
“In the US, we know that young children are exposed to screens in childcare … but the authors did not have this information in their study,” she said. “Parents in the U.S. should investigate whether their young children are spending time in front of screens in childcare if they want to limit this exposure.”
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