UK researchers found a significant link between children who checked their social media accounts more than three times a day and later feelings of psychological distress.
But they believe this is not directly as a result of social media use, but due to being exposed to cyber-bullying, not sleeping enough and screen use eating into time that could otherwise be spent exercising.
One solution could be for parents to insist their children leave their phones downstairs when they go to bed to ensure their sleep is not disrupted.
The authors said parents should worry less about how long children were spending on their phones and more about ensuring they get enough sleep and physical activity.
They should also monitor who their child is speaking to online in the same way that they would be aware of who their friends are in the playground.
Dr Dasha Nicholls, co-author of the study, said: “Rather than endlessly saying ‘can you get off your phone, can you get off your phone?’, what it’s saying (is) you need to leave your phone downstairs when you go to bed, you need to make sure that you go out and get some exercise and then you can play on your whatever it is, and to ask questions about whether anything negative has happened online and make sure that parents do what they can do to protect from cyber-bullying.”
Dr Nicholls, from Imperial College London, added: “In cyber-bullying, even your bed is not a safe place, and if your phone is downstairs, you can’t be bullied in your bed.”
The researchers analysed data on almost 10,000 school children from the Our Futures Government study as they progressed from age 13 to 16 during 2013-2016.
They found that 43% of girls and boys used social media more than three times a day in the first year, rising to 69% in the third.
The researchers found those who checked social media at this frequency in the first year were 31% more likely to experience psychological distress the following year.
Persistent frequent social media use in years one and two led to lower wellbeing in the third year for girls but not boys.
But the study authors believe social media itself is unlikely to be directly harmful; rather it is due to the content consumed or displacement of physical activity.
When they accounted for factors such as cyber-bullying, sleep and physical activity, the association all but disappeared in girls.
This was not the case for boys, suggesting other mediating factors, which have not yet been identified, were responsible.
Prof Russell Viner, the President of the Royal College of Paediatrics & Child Health, said he believes it would be “biologically implausible” for social media to negatively affect one gender and not another.
The study author said: “The causal arrow isn’t from social media, we believe, to distress, it actually comes through these other things that are enabled by social media.
“It’s about the content and the displacement, not about the platform or the use of social media.”
He added: “I think one of the conclusions is that social media does not displace physical activities in boys in the same way that it does in girls, which may be one of the reasons for this difference that we see.”
The study is published in The Lancet Child & Adolescent Health journal.