Cell phones, tablets that cause psychological well-being problems in children as young as two years old.
Scientists warn that children as young as two are developing mental health problems due to smartphones and tablets.
Just one hour a day watching a screen may be enough to make children more likely to be anxious or depressed.
This could make them less curious, less able to finish tasks, less emotionally stable and reducing their self-control.
Although adolescents are at greater risk of harmful devices, children under 10 and the developing brains of young children are also affected.
But research shows that 'zombie' children spend almost five hours every day looking at electronic devices.
Researchers at San Diego State University and the University of Georgia say that time spent on smartphones is a serious but avoidable cause of mental health problems.
"Half of mental health problems develop in adolescence," said professors Jean Twenge and Keith Campbell. "It is necessary to identify the factors linked to mental health problems that [can be modified] in this population, since most are difficult or impossible to influence." The way children and adolescents spend their free time is [easier] to change".
Parents and teachers should reduce the amount of time children spend online or watching television while they study, socialize, eat or even play sports.
Professor Twenge said her study, one of the largest of its kind, supports the time limit set for the American Academy of Pediatrics screen: one hour per day for children two to five years old.
It also suggests that a similar limit, perhaps two hours, should apply to children and adolescents of school age, he added.
The researchers analyzed the data provided by the parents of more than 40,000 American children aged two to 17 years for a nationwide health survey in 2016. The questionnaire asked about the medical care of the youth, any emotional, developmental or developmental problems. behavior and your daily screen time.
Teenagers who spend more than seven hours a day on screens are twice as likely to have been diagnosed with anxiety or depression as those who spent an hour. The study found that the links between screen time and well-being are stronger among teens than among young children.
Professor Twenge said: "At first, I was surprised that partnerships were bigger for teenagers, but teenagers spend more time on their phones and social networks, and we know from other research that these activities are more linked to low well-being that to the observation ". Television and videos, which is most of the screen time of the youngest children. "
Even moderate four-hour use is also associated with less psychological well-being than an hour a day.
Preschoolers, or children under five, who are frequent users are twice as likely to lose control of time, and are 46 percent more likely to not be able to calm down when they are excited.
Among young people aged 14 to 17, more than four in ten (42.2%) of those who participated in the study and spent more than seven hours a day on screens did not finish the tasks.
Approximately one in eleven (9 percent) of children ages 11 to 13 who spent an hour with screens daily was not curious or interested in learning new things.
Writing in the journal Preventative Medicine Reports, the professors said they were particularly interested in the links between screen time and diagnoses of anxiety and depression in young people, which have not yet been studied in great detail.
They said: "Previous research on the associations between screen time and psychological well-being among children and adolescents have been conflicting, which has led some researchers to question the limits of screen time suggested by medical organizations."
The US National Institute of Health UU He estimates that children and adolescents usually spend an average of five to seven hours on screens during free time. The evidence is growing of the adverse effects that this has on health.
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