Children who use social media for more than three hours per day are more likely to develop depression and anxiety compared to those who use it more moderately, according to a new study.
The data comes from Imperial College London’s Cognition, Adolescents, and Mobile Phones (SCAMP) study, which pools data from more than 2,300 children in schools across London. It is the largest study in the world looking at the impact of mobile phones and social media on children’s mental health, physical health and brain activity. The data was gathered between 2014 and 2018, and therefore reflects a different social media landscape to that of 2026.
The researchers found that children aged 11-12 who used social media for more than three hours per day were more likely to develop symptoms of depression and anxiety by the age of 13-15 than those who used it for fewer than three hours a day.
Children who used social media for over three hours per day were 47% more likely to have higher severity levels of depressive symptoms, 40% more likely to have higher severity levels of anxiety symptoms, 70% more likely to have clinically significant depressive symptoms, and 60% more likely to have clinically significant anxiety symptoms.
Lead researcher Dr Chen Shen said that the relationship between social media use and mental health outcomes is ‘complex’, and suggested that these mental health outcomes are ‘largely due to sustained disruptions to sleep’ when social media is used extensively in the evenings.
Further analysis by the same team demonstrated that insufficient sleep ‘mediated the associations of social media use and depressive and anxiety symptoms’. That is, the children who both used more social media aged 11-12 and also developed these symptoms aged 13-15 generally also were found to be getting insufficient sleep, and those who were not found to have this correlation were generally getting enough sleep. A ‘significant’ but ‘less pronounced’ association was also found between disruptions to sleep caused by phone alerts and the development of mental health symptoms.
A release from Imperial College London added that ‘while social media use by itself may not necessarily be causing harms, there is a pattern linked with excess use’ and that ‘better sleep hygiene could help to achieve a better life balance and reduce the potential mental health impacts.’
‘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,’ added Professor Mireille Toledano, a principal investigator of SCAMP.
The findings may seem to contrast with a previous large-scale study of schoolchildren in Australia, which found that totally banning social media had a negative effect on children’s mental health. However, these two datasets are not entirely in disagreement. Dr Ben Singh, the lead researcher on that study, told MediaCat that both excessive social media use and complete avoidance of social media had negative effects on children’s mental health, and that there is a ‘sweet spot’ where ‘teenagers who used social media in moderation consistently had the best wellbeing’.
Dr Shen added that the relationship between social media use and symptoms of anxiety and depression is ‘not as straightforward’ as ‘the well-established direct link between smoking and lung cancer’, and reiterated that the team ‘believe this is largely due to sustained disruptions to sleep’.
‘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,’ concluded Professor Toledano. ‘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.’
The researchers have announced that they will follow this work by trialling workshops in schools called Scroll Smart, which will teach children ‘how to moderate their social media use and the importance of sleep hygiene’.
‘If we can educate young people to use their phones in a more balanced way, we may not necessarily see social media use or phone use more generally as a problem to ban,’ explained Professor Toledano.
She added that ‘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’.
‘The evidence that this will solve all the issues children are facing just isn’t there,’ she concluded. ‘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.’
Social networking site use, depressive and anxiety symptoms in adolescents: evidence from a longitudinal cohort study (SCAMP) was written by Chen Shen, Braulio M Girela-Serrano, Martina Di Simplicio, Alexander Spiers, Iroise Dumontheil, Michael S C Thomas, Martin Röösli, Paul Elliott, Rachel B Smith, Mireille B Toledano, and published in BMC Medicine on 3 Feb 2026.
