toddlers with tablet

Screen time, although generally sedentary in nature, measures exposure to electronic screens such as phones, televisions, or computers (1). This specific sedentary activity seems to be on the rise. The time spent viewing media screens is increasing rapidly and has become the second most common type of sedentary behavior, behind adult sedentary jobs (2).


Increased time in front of a screen means less time being physically active, contributing to higher weight and BMI, increased caloric intake & unhealthy food choices. Studies have found that children may choose more active options if they are not watching TV. Additionally, children commonly eat more when they are watching TV, especially if they see ads for food. Commercials and other screen advertisements can lead to unhealthy food choices because most of the time, foods in ads that are aimed at children are high in sugar, salt, or fats. Limiting screen time can help children maintain a healthy weight as they grow.

While both sedentary behavior and screen time contribute to obesity due to lack of physical activity, there are numerous other conditions associated with screen time. According to social learning theory, children and adolescents learn by observing and imitating what they see on the screen, particularly when these behaviors seem realistic or are rewarding. Children 8 years and younger have not yet cognitively developed an understanding to comprehend persuasive content making them more vulnerable to advertising (3).


While some experts believe that well-designed educational programs may improve brain, literacy and social outcomes for young children, screen time should be limited and should not be permitted for children under 2 years old (except video calls with family). Allowing children to use media by themselves should be avoided. Digital media should be limited to 1 hour per day for children 2-5 years old (4). In child care centers, however, screen time should be limited to 30 minutes per week, it should be only for educational purposes and free of advertising (6). Parents should check with their provider’s policies to make sure the combined media time does not exceed 1 hour per day. Screen time should never be permitted during meals, snack time or within one hour of bedtime.


kids using tablets
  • Only use high quality programming and apps
  • Log screen time minutes and set limits; use timers
  • Avoid using media as a way to calm your child or keep him/her entertained
  • Create screen-free rooms and keep bedrooms, mealtimes, and parent–child playtimes screen free
  • Find alternative activities that don’t involve screen use
  • Turn screen time into active time (e.g. do physical activities during commercials)
  • Avoid using screen time as a reward or taking it away as a punishment (makes it too important)
  • Educate children about advertisements, commercials and programs they are viewing
substance abuse

Substance Abuse and Sexual Behaviors

Viewing advertisements on television and other screen time platforms such as video games, social media, and YouTube are likely to expose children to drugs, alcohol and sexual content which can lead to early onset deviant behaviors.

Mental Health

Acts of violence can lead to anxiety and fear. Because violence is often “glamourized” on television, acceptance of violence becomes an appropriate means of solving conflict resulting in learned aggression.

Cognitive Development

Heavy television-viewing (>2–3 hours/day) in early childhood has been linked with language delays and attention-deficit disorder during the early school years.


Increased duration of media exposure and the presence of computer, phone or television screens in the bedroom (which have been found to increase a child's watching to ~11 hours/day) have been associated with fewer minutes of sleep per night in young children. Even infants exposed to screen media in the evening hours show significantly shorter night-time sleep duration than those with no evening screen exposure (4). LEDs at night (iPads, phones, tablets) can interfere with the release of melatonin which affects sleep (5).

Children who have a TV in their bedroom watch 56% more TV daily than those who don’t. Children who watch TV for 3+ hours per day have a 65% higher chance of being obese than children who watch less than 1 hour.
child using a computer


  1. Lou, D. Sedentary Behaviors and Youth: Current Trends and the Impact on Health. San Diego, CA: Active Living Research; 2014. Available at
  2. Wu, L., Sun, S., He, Y., & Jiang, B. (2016). The effect of interventions targeting screen time reduction. Medicine, 95(27). doi:10.1097/md.0000000000004029
  3. Strasburger, Victor C., Amy B. Jordan and Ed Donnerstein. Health Effects of Media on Children and Adolescents, Pediatrics 2010;125;756; originally published online March 1, 2010; DOI: 10.1542/peds.2009-2563
  4. Radesky, J., MD, FAAP, & Christakis, D., MD, MPH, FAAP. (2016). Media and Young Minds. American Academy of Pediatrics,138(5). doi:10.1542/peds.2016-2591
  5. Heo, J., Kim, K., Fava, M., Mischoulon, D., Papakostas, G. I., Kim, M., . . . Jeon, H. J. (2017). Effects of smartphone use with and without blue light at night in healthy adults: A randomized, double-blind, cross-over, placebo-controlled comparison. Journal of Psychiatric Research, 87, 61-70. doi:10.1016/j.jpsychires.2016.12.010
  6. Caring For Our Children 3 Content. (n.d.). Retrieved February 07, 2018.
  7. Nutrition and wellness tips for young children: provider handbook for the Child and Adult Care Food Program. (2013). Alexandria, VA: U.S. Dept. of Agriculture, Food and Nutrition Service. Retrieved January 30, 2018.
Lindsay, A. and Byington, T. 2020, Screen Time | Make Time to Unplug, Extension, University of Nevada, Reno, FS-20-21

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