Children aged 12 to 13 are the most at risk of mental health issues from heavy use of social media and show a worrying decline in their psychological wellbeing after just one year.
These are the findings of a landmark decade-long study, led by the Murdoch Children’s Research Institute and published in the Medical Journal of Australia, which examined the behaviour and mental health of almost 1200 Melbourne children.
The researchers found that during the ages of 12 to 13, the dangers of using social media for two hours or more a day rose sharply, particularly among girls.
They found that for every 100 girls of this age group who were using social media for at least two hours daily, there were about 11 additional cases of high depressive symptoms and poorer wellbeing detected a year down the track, when compared with peers who used it for less than an hour a day.
Dr Nandi Vijayakumar, a cognitive neuroscientist at Deakin University and a lead researcher of the study, said the risk peaked during early adolescence for several reasons including the onset of puberty and the beginning of a time when girls become increasingly sensitive to peer approval and exclusion.
“This is when young people first start using social media, typically, and learning how to navigate online interactions, but it is also a period of rapid brain development and important social changes,” Vijayakumar said.
She said parts of the brain responsible for emotion regulation were also still maturing, meaning adolescents might be less equipped to manage the more challenging aspects of social media, such as social comparisons and bullying.
“While the effects were modest at the individual level because this is so common among adolescents, even modest increases in risk could translate into potentially meaningful impacts at the population level,” Vijayakumar said.
While the findings are concerning for parents, researchers say the study also identified a critical age window for intervention.
Melbourne teenager Lauren Linton was 12 when the city was plunged into coronavirus lockdowns, sending her online use soaring. She was left communicating with her friends via social media including through app Snapchat. It was tough and fuelled her anxiety.
“I remember there being quite a bit of bullying and drama, and some of the girls would make group chats and leave the other girls out,” Linton said.
“You’re so young at the time. You really don’t understand the huge impact leaving somebody out like that can have on someone at an age when all you really want to do is fit in.”
Linton and her friend Kyra Posser have grown up using social media.
They said that as they got older it had become easier to navigate, and they still spend hours a day on Snapchat, TikTok and Instagram. Both said there were positives and negatives.
“During the pandemic it became the only way we could stay in touch,” Posser said. “Now, we still use it all the time to chat or make plans to see other.”
The study found boys aged 12 to 13 also faced a decline in their mental health if they used social media for more than two hours every day.
Researchers observed about an additional seven cases of high depressive symptoms and poorer mental health per 100 boys, when compared with those who limited their time online to less than an hour a day.
The research focused on the years 2015 to 2021 when children were between the ages of 12 and 18.
The findings come six months after Australia introduced its controversial under-16 social media ban and as debate still rages over whether it has been successful at helping to protect young people online.
Critics argue many teenagers are still using social media and that the restrictions are difficult to enforce, while Australia’s eSafety Commissioner, Julie Inman Grant, broke ranks with the federal government telling this masthead she was “not really keen” on it, and it was based on legislation drafted “very quickly”.
Data shows the ban has not been very effective so far – about 70 per cent of children who held accounts on Snapchat, TikTok, Instagram, Facebook and YouTube before the ban are still using them.
Prosser, who turned 18 in March, said her mother had enforced a screen time limit for her, which automatically shuts down her apps after three hours.
But she said most teens under the age of 16 she knew had found ways to bypass the social ban.
While the study found all children in early adolescence were deemed most vulnerable between the ages of 12 and 13, their psychological distress manifested in slightly different ways.
For girls age 12 to 13, excessive scrolling and social media activity was linked to the largest overall risk of feelings of depression, anxiety and poor wellbeing.
However, boys who were the same age and spent hours a day online exhibited a slightly higher increase in their risk of self-harming behaviours than girls.
This is despite girls generally being at higher risk of self-harm than boys for much of their adolescence.
Vijayakumar said the results supported a focus on early adolescence as a critical window for intervention.
“Early adolescence stands out as a time when higher levels of social media use are linked to a greater risk of mental health problems one year on,” she said.
“While the increases in risk were modest in our study, even small effects can have important public health implications when large numbers of young people are exposed. This is why early adolescence may be the key time to intervene.”
However, she noted the risk did persist beyond early adolescence, suggesting that age-based restrictions alone might not be sufficient.
Murdoch Children’s Research Institute’s Professor Susan Sawyer, who also led the study, said the findings backed the need for a balanced approach to social media policies.
“Concerns about the impact of social media on adolescent mental health have fuelled community and policy debates globally and driven Australia’s world-first social media legislation,” she said. “Despite all this, robust evidence of population level impacts has remained limited, making our findings particularly significant.”
She noted that many adolescents also report positive experiences with social media including a sense of belonging and self-expression.
However, high levels of mental health problems, cyberbullying and exposure to harmful online content have sparked widespread alarm.
Sawyer said that for most young people, spending more than 2½ hours online daily was the norm.
“Our results don’t suggest that social media is universally harmful, but it’s not without some harms,” Sawyer said.
“It reinforces the need for age-appropriate limits, better education and literacy programs and clearer parental guidance.”
Daniel Donahoo, of anti-bullying group Project Rockit, said that while longitudinal studies such as these were crucial to inform decisions made by regulators, there was a risk they underestimated how self-aware and informed young people were.
“We often treat it as though young people are not actively thinking about how they use social media, but in our experience working with hundreds of thousands of them in schools, they actually are thinking quite deeply and critically about this,” he said.
“They’re also thinking about things like climate change and AI. It’s really challenging to be a young person now, but they seem to really understand the complexity of their world.”
Start the day with a summary of the day’s most important and interesting stories, analysis and insights. Sign up for our Morning Edition newsletter.
Melissa Cunningham is a health reporter for The Age. She has previously covered crime and justice.Connect via X or email.
