by Elizabeth Cespedes, MS

Children in the United States consume an average of 7 hour/day of screen media.  Television is the biggest culprit, but time spent on cellular phones, in front of the computer, on a tablet, or playing video games contribute a good bit of that time too.

Screen media is present throughout children’s lives – at school, in free time and even in bedrooms. But is this constant exposure bad for children’s health? The answer seems to be yes, especially because of the link between excessive screen time and less sleep. Multiple studies have found that more time spent viewing television or other screen media predicts less daily sleep in children, from infancy through adolescence. Having a television or a computer in the bedroom is worse, leading to more total media use, and regardless of this total use, to a later bedtime and fewer hours of sleep.

Time spent in front of the screen can displace time spent in other activities such as reading, physical activity or sleeping. There may also be biological effects of screen media use before bedtime that explains why bedroom screens seem to be especially harmful. The content of the programming, whether scary or exciting, may lead to mental and emotional arousal that makes it difficult to go to sleep. And, exposure to blue light can directly impact children’s sleep-wake rhythms. These rhythms are regulated by a master circadian “clock” found in the brain, and light calibrates this clock. Blue light released from screens suppresses melatonin production leading to delayed sleep onset.

Overall, sleep loss can have negative effects on children’s behavior, attention and academic performance. Additionally, shorter sleep in childhood has been linked to excessive weight gain and risk of childhood obesity.

Beyond losing sleep or displacing time spent in other activities, greater exposure to screen media means seeing more marketing, typically for unhealthy foods. Studies show that children as young as three recognize commercials but may not understand their persuasive intent. These advertisements aren’t limited to the TV. Other types of screen media are prevalent and might influence risk of overweight and obesity in children and adolescents.

So what can families do? Several interventions have been showed to be effective in reducing children’s screen time, including using electronic TV monitoring devices, contingent feedback systems (e.g. screen time is earned by time spent cycling), and clinic-based counseling. Another promising strategy for reducing screen time and preventing childhood obesity is to focus on the entire home environment and to improve multiple family routines and habits that might have synergistic benefits for children’s health. Key behaviors include reducing screen time, establishing a screen-free bedtime routine, increasing the number of family meals without the television and time spent in active play.

Parents’ actions on screen time depend on the age of the child as well. Though the American Academy of Pediatrics recommends no screen time for children under 2 years, eliminating all screen exposure for older children is not realistic or even desirable. Screens can be helpful as well as harmful. Media can be used as an educational tool in the classroom, and for teens, social media is often a way to feel connected to peers. But monitoring children’s media diets – how much and what’s in it – might improve children’s health.

About the Author:

About the author: Elizabeth Cespedes is currently a doctoral candidate in the departments of Nutrition and Epidemiology at the Harvard School of Public Health investigating sleep and diet in relation to obesity and diabetes in adult and pediatric cohorts, including Project Viva. She has worked with the OPP since 2011 including as a bilingual health educator for Healthy Habits, Happy Homes and as a research assistant helping to adapt High Five for Kids for the Mexico City context.



Your comment will be posted after it is approved.

Leave a Reply