Children who spend more than three hours a day on social media are more likely to develop mental health problems, including depression and anxiety, according to new research.
Experts suggest the relationship between these platforms and mental health is “complex”, with sleep disruption identified as a primary factor driving these effects.
Researchers at Imperial College London analysed data from the Study of Cognition, Adolescents and Mobile Phones (Scamp), which was set up in 2014, and included 2,350 children from 31 schools across London.
Participants completed a questionnaire detailing their digital behaviours, mental health, and lifestyles, as well as cognitive tests in Year 7, aged 11 to 12, and then again when they were between 13 and 15 years old.
The study found that children who spent more than three hours on social media a day were more likely to have more symptoms of anxiety and depression as teenagers than those who spent 30 minutes scrolling each day.
Researchers suggest this could be down to sleeping less, particularly on school nights, and going to sleep later.
Dr Chen Shen, of Imperial’s school of public health, said: “The relationship we see is complex, so it’s not as straightforward as saying that social media use directly causes poor mental health in children, like the well-established direct link between smoking and lung cancer, for example.
“But we see that children who use social media above a certain level when they are in year seven are more likely to develop mental health problems when they reach years nine and 10, and we believe this is largely due to sustained disruptions to sleep.”
The findings, published in BMC Medicine, support the development of a curriculum in secondary schools that raises awareness of digital literacy and sleep, researchers said.
They also highlight that more studies may be needed as the social media landscape has changed dramatically since the data was collected between 2014 and 2018.
Dr Shen added: “We know social media platforms have changed enormously over the last decade and are likely to change as much, if not more, in the next five to 10 years.
“As the platforms, usage and content evolve, we need continued research to understand how social media use affects children’s mental health in today’s digital environment.”
Professor Mireille Toledano, principal investigator of Scamp and Mohn chairwoman in child health at Imperial’s school of public health, said: “Our analysis shows a clear trend in terms of the amount of time spent on social media and mental health outcomes.
“Children who use social media apps for longer, and later into the evening, may be offsetting the sleep they need to function healthily. We think this is the key reason we’re seeing a lasting impact on their mental health down the line.
“There seems to be growing support for a total ban on social media use for under-16s, and for the current non-statutory guidance of no phones in schools to become a legal ban.
“But, at the moment, we don’t actually have the evidence to support these bans or claims that social media or mobile phone usage are harmful in themselves. The picture is complex and multi-factorial, and we need to better tease out what is driving the associations we see.”
Earlier this month, the government launched a consultation to gather views on measures to protect children online, which could include a partial social media ban for under-16s.
Prof Toledano added: “While measures to restrict children’s exposure to potentially harmful online content are necessary and should be welcomed, currently there just isn’t enough scientific evidence to suggest that social media use by itself is harmful for children.
“Despite calls for an outright ban for under-16s, the evidence that this will solve all the issues children are facing just isn’t there.
“Instead of the UK jumping on an arbitrary ban, it might be prudent to see what happens in Australia over the course of this year and the impacts of the ban on young people’s health and wellbeing.”
