Below are negative effects
of screen time including current AmericanAcademy of Pediatrics and World
Health Organization recommendations for screen time.
At the bottom is a summary of child, teen,
and adult screen time negative effects.
The World Health Organization (WHO)
and American Academy of Pediatrics (AAP) have made screen time recommendations. AAP calls for no screen time
at all for children until 18 to 24 months, except for video chatting, and reports children ages 2 to 5
should get an hour or less of screen time per day. The WHO similarly recommends no screens for kids under 2,
and less than an hour a day for kids 2 to 5.
“The basic pattern that has been found
in dozens of studies is that children learn better from a person who is with them face-to-face than from
a person on a screen, even if it’s the exact same person doing the exact same thing,” says
Georgene Troseth, PhD, a psychologist at Vanderbilt University.
Evidence is strong that
screens aren’t an effective teaching tool for the baby and toddler set, and they could
displace the kinds of face-to-face interactions that actually help young kids learn. A 2005 review
led by developmental psychologist Daniel Anderson, PhD, now a professor emeritus at the University
of Massachusetts, Amherst, found that television viewing consistently failed to teach kids age 2 and
younger as much as live interaction (American
Behavioral Scientist, Vol. 48, No. 5,
“video deficit” was seen in simple imitation tasks, in language learning and in
Research has shown evidence to
support limiting screen time for babies and young children. One longitudinal study of 2,441 mothers and
children, led by University of Calgary psychologist Sheri Madigan, PhD, found that more time per week
spent on screens at ages 24 months and 36 months was linked with poorer performance on screening tests
for behavioral, cognitive and social development at 36 months (JAMA
Pediatrics, Vol. 173, No. 3,
Early data from a landmark
National Institutes of Health (NIH) study that began in 2018 indicates that children who spent
more than two hours a day on screen-time activities scored lower on language and thinking tests, and
some children with more than seven hours a day of screen time experienced thinning of the brain’s
cortex, the area of the brain related to critical thinking and reasoning.
Increasing screen times results in
increase of blue light. Blue light coming from any screen has been shown to disrupt
sleep. There are filters
in certain devices, but not all have this capability.
Muscles around the eye,
like any others, can get tired from continued use. Concentrating on a screen for extended periods
can cause concentration difficulties and headaches centered around the temple and eyes. Children may
also use screen devices where lighting is less than ideal, causing fatigue from squinting.
Gazing at the same
distance for an extended time can cause the eye's focusing system to spasm or temporarily
"lock up." This condition, called an accommodation spasm, causes a child's vision to
blur when he or she looks away from the screen. Some studies also suggest computer use and other
close-up indoor activities may fuel rising rates of myopia (nearsightedness) among children,
although this is not yet proven. More time playing outside may result in healthier vision
development in children.
Studies show that people
blink significantly less often when concentrating on a digital screen, which can leave eyes dry and
irritated. Desktop and laptop computer use can be especially tough on children's eyes, because
they're usually situated higher up in the visual field than a book, for example. As a result,
the upper eyelids tend to be open wider—speeding up evaporation of the eye's tear
The firmest associations
are between screen time and obesity and screen time and depressive symptoms, according to a
systematic review of reviews published by University College London (UCL) psychologist Neza Stiglic,
PhD, and Russell Viner, PhD, a professor of adolescent health at UCL (BMJ
Open, Vol. 9,
No. 1, 2019). Most research on obesity
focused on television viewing and found that more time spent watching TV was associated with a
higher body mass index or body fat composition. Multiple studies also found that screen use of more
than two hours a day was correlated with depressive symptoms. The reviewers found moderate evidence
linking screen time to poorer quality of life, higher caloric intake and less-healthy
There is evidence that
children who watch a lot of television during the early elementary school years perform less well on
reading tests and may show deficits in attention.
According to one study, infants 6 to 12 months old who were
exposed to screens in the evening showed significantly shorter nighttime sleep than those who had no
evening screen exposure.
For preteens and teenagers, excessive
use of screens late at night will affect their sleep, and keeping screens out of the bedroom is
advised. Too much time spent on social media as well as lack of sleep can affect behavior and
cognitive performance in school and interfere with learning. It has also been shown that excessive
screen time and sleep deprivation are linked to obesity, which in turn can affect self-esteem and
lead to social isolation and more screen time.
According to a recent study, 92 percent of babies had
used a mobile device before their first birthday. Nearly 35 percent have their own mobile device at age 2
and that number is 75 percent among 4-year-olds. Nearly a quarter of kids ages 2 and under have TVs in their
rooms, and at age 4, almost 50 percent do. On the other hand, the American Academy of Pediatrics Studies
suggest that screen time may be affecting the normal development of fundamental learning, language, and
Learning. Kids younger than 30 months have a limited ability to learn
from video, according to some studies. They learn more from live interaction with people and immediate
feedback. The American Academy of Pediatrics discourages media use by children under 2 and says there is
no proven educational or developmental benefit at this age. Screen time also takes away from
unstructured play time, which is important for learning and problem solving.
Language skills. Research has shown that TV can hamper language development in
kids by displacing time spent interacting with caregivers.
Emotional development. Some experts worry that using digital devices as
“shut-up” toys to occupy kids during day-to-day tasks like grocery shopping or eating out
might prevent them from learning how to regulate boredom, distress, and other impulses and
Vision. In recent years, many countries are experiencing epidemic
levels of myopia, or short-sightedness, and indoor time may be to blame.
Sleep. Research has linked screen use among children with shorter,
lower-quality sleep. A 2014 review paper of school-aged kids and adolescents correlated screen time with
poorer sleep. They saw especially strong links between screen time and delays in bedtime, as well as a
shorter period of time spent asleep. A study published a year later found that compared with kids who
didn’t sleep near a small screen (like a cellphone screen), those who did sleep near a small
screen reported about 20 fewer minutes of sleep and were more likely to report insufficient rest or
Weight. Several studies have found that the more TV children
watch, the more like they are to be overweight. Kids with TVs in their bedrooms are more at risk, and
childhood TV habits affect the risk of being overweight as adults.
During the preteen and teen years, the brain goes
through major transformations. This may be why teens are especially vulnerable to the impacts of screen time
on brain function and emotional well-being.
Learning. One study found that kids and young adults who spend a lot of
time on TV and video games were twice as likely to suffer from attention
Self-confidence. More time watching videos or other content on digital devices
means less time exploring and creating their own experiences, stories, or art.
Social skills. Online experiences can build community and foster communication
and creativity. Teens might hide behind the screen to avoid tricky or awkward conversations. That lack
of face-to-face interaction can also feed online bullying.
Emotions and personality. In 2010, researchers found that kids who logged more than two
hours a day in front of a computer or TV screens had a higher chance of psychological difficulties on a
standard questionnaire. Studies in young men show that playing violent video games is linked to more
aggression and less sensitivity to others. Also, imaging studies have found that internet addiction and
game addiction can shrink the brain regions responsible for planning and executive functions, empathy,
compassion, and impulse control.
Addiction and reward seeking. A recent survey found that 50 percent of teenagers admitted being
addicted to their mobile devices. The brain’s dopamine center is extra sensitive during the
teenage years, making the rush of playing video games feel even more intense and addictive.
Sleep. Similar to the findings in adults, screen time can have
damaging effects on sleep. A 2015 study of 10,000 16- to 19-year-olds in Norway reported that those who
clocked in four or more hours of screen time a day (outside of schoolwork and homework) had about a 50
percent higher likelihood of lying awake for an hour or more before finally falling asleep. And
according to a recent study, lack of sleep with teens is linked to more risky behaviors like drinking
Weight and overall health. Just like in adults, watching two or more hours of TV is
linked to weight gain in this age group. Studies have also noted higher cholesterol and blood pressure
in kids who watch more TV.
A 2014 Nielsen report found that adults log a total
of 11 hours of screen time a day. Here are some of the ways this might be affecting our health:
Vision. Staring into a screen for extended periods of time can cause
“computer vision syndrome.” You’re probably familiar with the symptoms: strained, dry
eyes, blurred vision, and headaches. Poor posture can also cause neck and shoulder pain.
Sleep. Studies link heavy computer and mobile phone use to more sleep
disturbances. Blue light from digital devices suppresses the sleep-promoting hormone melatonin, keeping
us from having restful sleep.
Addiction and reward seeking. Dopamine, the “feel-good hormone,” is part of
the brain’s pleasure and reward circuits. Playing video games turns on similar brain regions as
those linked to cravings for drugs and gambling.
Weight. Even two hours of TV a day can increase the risk of
weight gain, diabetes, and heart disease in adults. There are probably several factors to blame,
including less active time, less sleep, and seeing more ads for unhealthy foods.
Overall health. Most of the time we’re on our screens, we’re
sitting down. Sitting for hours at a time boosts the risk of obesity, heart disease, type 2 diabetes,
and some types of cancer. One study found that spending more than four hours a day in front of a
computer or TV more than doubles your likelihood of dying or being hospitalized for heart disease and
exercise won’t reduce the risk.