What is the “right age” to give your child a smartphone? It’s a question that worries many parents — torn between insistent requests from pre-teens and researchers warning about the potential harms of constant connectivity. But new findings strengthen the case for delaying that delivery.
The study, published in the journal Pediatrics this Monday (1st), found that children who had a smartphone at the age of 12 were at greater risk of depression, obesity and insufficient sleep than those who did not yet have one. Researchers analyzed data from more than 10,500 children who participated in the Adolescent Brain Cognitive Development Study — the largest long-term study of childhood brain development in the United States to date.
The younger children under 12 were when they received their first smartphones, the greater their risk of obesity and poor sleep, the study found. The researchers also focused on a group of children who hadn’t gotten a phone until age 12 and found that, a year later, those who got one had more unhealthy mental health symptoms and poorer sleep quality than those who didn’t.
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“When you give your child a phone, you need to think of it as something significant for the child’s health — and act accordingly,” said Dr. Ran Barzilay, lead author of the study and a child and adolescent psychiatrist at Children’s Hospital of Philadelphia.
A better understanding of risks
The new study only shows an association between receiving a smartphone earlier in adolescence and worse health outcomes, not a cause-and-effect relationship. But researchers point to previous studies that suggest young people with smartphones may spend less time socializing in person, exercising and sleeping — all essential for well-being. Adolescence is a sensitive time, when even modest changes in sleep or mental health can have profound and lasting effects, they note.
The aim of the study is not to blame parents who have already given devices to their children, Barzilay said. And he’s realistic about how smartphones are ingrained in American adolescence.
The lesson, he said, is that age matters.
“A 12-year-old is very, very different from a 16-year-old,” he said. “It’s not like a 42-year-old versus a 46-year-old.”
The median age at which children in the study received their first smartphones was 11 years old. And virtually all American teenagers now say they have access to a smartphone, according to a recent Pew report.
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Jacqueline Nesi, an assistant professor of psychiatry and human behavior at Brown University who writes the Techno Sapiens newsletter about parenting in the digital age, cautioned that the new study cannot prove that smartphones directly cause harm.
“It’s incredibly difficult, if not impossible, to get this kind of causal evidence on this topic,” she said, although the results may “encourage” parents to delay smartphone ownership when possible.
Officials “don’t need to wait for perfect evidence to make these types of decisions,” Nesi said. They should feel confident to trust their gut, he added, and hold off on handing over the smartphone until everyone is ready — including parents, who have to do the difficult work of establishing protections and boundaries.
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“Giving a child a device with access to everything on the internet will be risky,” he said.
The importance of protecting sleep
While researchers may continue to debate the negative effects of smartphones on children, most agree that the devices can prevent young people from getting the sleep they need.
Dr. Jason Nagata, a pediatrician at the University of California, San Francisco, highlighted a 2023 study he worked on, also using the Adolescent Brain Cognitive Development Study sample, which found that 63% of 11- to 12-year-olds reported having an electronic device in their bedroom. And almost 17% said they had been woken up by phone notifications in the last week.
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Taking phones out of the bedroom at night is a simple step families can take to mitigate some of the negative health effects associated with smartphones — even if parents have already given their child a device, Nagata said.
But he and others acknowledged how difficult this can be for families.
Barzilay has three children, two of whom received smartphones before they were 12 years old. But, he said, his 9-year-old son won’t have one anytime soon.
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He encouraged other parents to consider new data about the potential risks of early smartphone ownership when deciding when to give their child a device.
“This doesn’t mean that every child with a smartphone will have a lifelong problem,” he said. “All it means is that we as parents — and, hopefully, policymakers and society — are going to do something about this together.”
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