Social media use and screen time can lead to an increase in depression and anxiety among teens and adolescents, a new study finds.

According to a study published in the Canadian Journal of Psychiatry, researchers observed more than 3,000 seventh to 10th graders in the greater Montreal area over a period of four years.

Researchers measured how much time students spent in front of social media, television and computers. The data revealed the more time kids spent engrossed in digital screens, their symptoms of anxiety and depression became more severe.

Not all forms of screen use yielded the same impact on their mental health, says Patricia Conrod, one of the study’s researchers.

“In terms of the relationship between screen time and depression, what we found was that social media was very robustly related to increases in depressive symptoms, as was television,” she says. “And there was no relationship between video gaming and depressive symptoms.”

When watching TV, kids often consume idealized lives that are different from their own experiences, she says. But social media is unique because adolescents are seeing pictures, videos and status updates from their own network of friends and peers.

“In some way, you're being exposed to a slightly biased perspective on what young people's lives are like and you compare yourself to that,” she says.

Most adults experienced their childhood and teenage years without social media. Conrod says many adults developed a “more balanced perspective on what everyday life is like” since they did not have digital access as kids.

But digital technology is more accessible than ever, and adolescents tend to spend a good chunk of their day using it — teens average around seven hours per day on social media, while tweens clock in around five hours per day. In 2018, roughly half of U.S. teens said they spend too much time on their cellphones, according to the Pew Research Center.

This consistent use can blur the lines of reality for adolescents whose brains are still developing, Conrod says.

“Adolescents today spend a lot more of their time interacting with others through social media and therefore exposed to a reality that is biased,” she says.

Conrod says she is concerned that the filtered lives of others that many young people see while scrolling on their phones could influence how they critically examine information.

Multi-screening, the act of being exposed to more than one screen at a time, also contributes to whether young people can effectively parse out what’s biased and what’s not, she says. When you’re in front of multiple screens, “you become less critical of the information you're being exposed to because your attention is divided,” she says.

“If you're spending a lot of your time being exposed to biased information, there's a risk that you're going to develop a somewhat biased perspective of the world,” she says. “And that's concerning to me.”

Marcelle Hutchins produced and edited this interview for broadcast with Kathleen McKenna. Serena McMahon adapted it for the web.