An Australian study tracking nearly 1,200 Melbourne children found that adolescents using social media for at least two hours a day had higher odds of depressive symptoms and poorer wellbeing one year later than peers who spent less than one hour daily.
By the time a teenager hits the scroll—the late-night feed, the constant checking, the “just one more”—it can feel harmless. A new Australian study suggests that feeling may be wrong, especially once phones and social apps start taking over the same room as stress.
Researchers led by the Murdoch Children’s Research Institute found that adolescents who spent at least two hours a day on social media were more likely to experience depressive symptoms and poorer wellbeing one year later than those who used social platforms for less than one hour a day.
The study does not claim social media directly caused those mental health problems. But the connection carries weight because it followed young people over time rather than relying on short-term data.
The research followed almost 1,200 children in Melbourne from age nine to 19 as part of the Child to Adult Transition Study. Each year, the team collected data on social media use and mental health outcomes, including depression, anxiety, and self-harm.
One group stood out: girls aged 12 to 13. That age range produced the strongest association, and the researchers describe it as a critical window for intervention. Dr Nandi Vijayakumar of MCRI and Deakin University said early adolescence stood out as a period when heavier social media use was linked to a greater risk of mental health problems one year later.
There’s a reason that timing matters. Ages 12 and 13 are often when phones, social apps, peer pressure, and other factors start colliding at once. Even a modest rise in risk can matter when millions of young people are exposed to the same platforms every day.
Still, the study doesn’t paint social media as universally toxic. Researchers noted that for some teenagers, social media can support belonging, self-expression, and friendship-based support systems—especially for young people who may struggle to find those communities offline.
At the same time, higher usage can bring other pressures: more exposure to cyberbullying, harmful content, and social comparisons. Researchers also pointed to knock-on effects such as sleep disruption and the pressure to stay available.
Professor Susan Sawyer from MCRI said the results do not show social media is universally harmful, but they do support age-appropriate limits, better digital literacy, and clearer parental guidance.
The findings land as governments continue debating age restrictions and platform rules for young users. Australia has already introduced world-first social media age restrictions, and MCRI and Deakin University are separately studying how those changes affect teens’ phone use and mental health.
The tension in the data is clear: social media may not be a single switch that flips mental health one way or another. But the study’s timeline—and the two-hour threshold it points to—suggests that when usage climbs during early adolescence, the risk isn’t theoretical.
social media teen mental health Australian study Murdoch Children’s Research Institute depressive symptoms digital literacy cyberbullying age restrictions
So basically phones are bad. Great, thanks.
I saw “two hours on social media” and thought it was gonna be like instant depression or something. But they’re saying it’s not direct cause?? Either way, seems like late-night scrolling is rough.
Wait, is this just about girls? Like it says girls 12-13 had the strongest association, but then it’s “nearly 1,200 Melbourne children.” So what about the boys just watching the same stuff? Sounds like they’re mixing it up.
This feels obvious though. At my cousin’s kid’s school they have phones out all day anyway, so “two hours a day” is like… even less than what they do. Also one year later like how do you control anything else, stress, school, parents, like it’s probably just life getting worse and phones happen to be there. But yeah, tell me again social media doesn’t cause it lol.