The connection between frequent use of social media and depression in children and teens has been the subject of a good deal of research. Some research has shown that, on its own, social media use doesn't affect a child or teen's level of depression — it's that depressed kids are likely to scroll more often.

But now a new study draws a direct line between social media use among preteens and rising rates of teenage depression.

Kids' social media use rose from seven to 73 minutes per day on average over the three years of the study. During the same period, their depressive symptoms went up 35 percent.

The University of California, San Francisco research team analyzed data on nearly 12,000 kids between the ages of 9 to 10 years old and then again three years later when they were 12 to 13 years of age, making it the first study of its kind to use within-person longitudinal data. This means it allowed researchers to track changes in each child over time and to accurately assess the link between social media use and depression.

Kids' social media use rose from seven to 73 minutes per day on average over the three years of the study. During the same period, their depressive symptoms went up 35 percent.

“There has been ongoing debate about whether social media contributes to depression or simply reflects underlying depressive symptoms,” lead researcher, Jason Nagata, an associate professor in UCSF's Department of Pediatrics, said in a press release. “These findings provide evidence that social media may be contributing to the development of depressive symptoms.”

Although this study did not look into why or how social media boosts depression in these kids, past research has pointed to bullying and cyberbullying as contributing factors.

But getting young people off the internet isn't easy, and it's complicated since it can also be a healthy way for them to stay in touch with their peer group. So, what's the answer?

Simply telling children to get off their devices won't work. It's better to lead by example and have nonjudgmental conversations about screen use.

“Setting screen-free time for the whole family such as during meals or before bed,” Dr. Nagata suggests, “can help build healthier digital habits for everyone, including adults.”

“It's never too early to develop a screen-time plan with your family,” The American Academy of Child and Adolescent Psychiatry (AACAP) advises. “Let your children share their ideas and concerns.” Here are a few additional tips from them:

  • Familiarize yourself with the programming your child is using to make sure it is age-appropriate.
  • Talk to your child about what they are viewing. Point out good behavior, such as cooperation, friendship and concern for others.
  • Be aware of how advertising influences choices.
  • Encourage your child to engage in other activities such as sports, music, art and hobbies that do not involve screens.
  • Set a good example with your own safe and healthy screen habits.
  • Teach children about online privacy and safety.
  • Consciously decide when your child is ready for a personal device.
  • Encourage using screens in ways that build creativity and connection with family and friends.
  • Consider your child or teen's maturity and habits. The right plan for one family may not be a good fit for another.

Simply telling children to get off their devices won't work, Nagata, the father of two young kids, says. “Parents can lead by example with open, nonjudgmental conversations about screen use.”

The study is published in JAMA Network Open.