When should your child get a smartphone? New UCSF study explains its link to eating disorders

SAN FRANCISCO (KGO) -- A new national study is raising questions about when children should get their first smartphones and what early access could mean for their relationship with food and body image.

The study, published Friday in JAMA Network Open, followed 8,957 U.S. adolescents over two years. Researchers found that children who owned a smartphone at age 12 had a higher risk of several eating disorder symptoms by age 14.

Nearly 70% of the children in the study had a smartphone at age 12. After researchers accounted for earlier eating disorder symptoms and a range of demographic, developmental, mental health and family factors, smartphone owners had a 67% higher risk of binge-eating symptoms and a 50% higher risk of inappropriate behaviors meant to prevent weight gain. They also had about twice the risk of tying their self-worth to their weight.

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At age 14, 24.2% of children who had owned a smartphone at 12 reported at least one eating disorder symptom, compared with 15.5% of those who had not.

UCSF pediatrician Dr. Jason Nagata, the study's lead author, said early adolescence can be an especially sensitive time for body image.

"Having a smartphone can just put a world of appearance focused content in the young person's pocket," Nagata said.

The study found an association and does not prove smartphones caused eating disorders. Researchers said more work is needed to understand exactly what may be driving the link.

Still, some parents told ABC7 Eyewitness News the findings did not surprise them.

"Social media. I mean, it plays a big role in what people see day to day or children's day to day," aunt Jessica Custodio said.

Another parent, Natalie, pointed to the body types children can encounter online.

"They're seeing a lot of like YouTube and social media models who are who are unrealistic, unrealistically thin," she said.

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That online environment is also changing as influencers document body transformations, "looksmaxxing" trends spread online and celebrity use of GLP-1 weight-loss drugs becomes part of popular culture.

San Francisco author and weight discrimination expert Virgie Tovar said drugs such as Ozempic have helped shift the conversation around body size.

"I think it's obvious that Ozempic has really changed the culture," Tovar said.

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Tovar also pointed to what she described as a cultural whiplash. After years of body positivity becoming more visible in advertising and popular culture, she said the rapid return of ultra-thin body ideals can be difficult to process.

"I think to see that walked back on so rapidly is extremely disorienting," Tovar said.

Researchers did not identify a specific age when a child should receive a smartphone. Nagata said families have different needs, but parents should pay attention to what children are seeing once they have access.

"I think it's just really important for parents to stay involved with their children's digital lives," Nagata said.