For teen girls, exercise and sleep may have more impact on mental health than social media Sladic/Getty

Social media isn’t necessarily bad for teens’ mental health – it only causes problems for girls when it interferes with sleep and exercise or enables cyberbullying. Boys don’t seem to be affected in the same way.

“The message is simple: don’t worry so much about how much your kids are on social media during the day,” says Russell Viner at the University College of London Great Ormond Street Institute of Child Health in the UK. “Worry about what they’re watching, the content, and make sure they get enough sleep and physical activity.”

Viner and his colleagues have looked at data already collected as part of another large study on young people in England. As part of that study, 12,866 people aged between 13 and 14 were interviewed in 2013. Just under 11,000 of them were interviewed again in 2014, and almost 10,000 again in 2015.


The participants filled in questionnaires about their mental health and wellbeing – including their levels of sleep and physical activity – as well as their experiences of cyberbullying. Each person was asked how frequently they used social media networks, messaging or photo-sharing services, including Facebook, Twitter, Instagram, WhatsApp, Blackberry Messenger, Snapchat, Tumblr, or anything else.

The team found that girls who used social media more frequently tended to be less happy and less satisfied with life, and were more anxious than those who said they didn’t use social media as much.

But social media itself isn’t necessarily to blame, says Viner. When his team accounted for sleep, physical activity and cyberbullying, the effect of frequent social media use on the girls’ wellbeing became insignificant. This suggests that social media only becomes problematic for girls when it starts to impact their sleep, exercise or exposure to bullying.

“Bullying in person is still much more common than cyberbullying. Almost nobody is cyberbullied who isn’t also being bullied face-to-face,” says Dasha Nicholls at Imperial College London in the UK, who co-authored the study. Tackling bullying itself is more likely to improve wellbeing than cutting a teenager’s access to social media, the team says.

Social media also often plays a positive role in a young person’s life, says Michelle O’Reilly at the University of Leicester in the UK. “Some young people use social media in quite negative ways, whereas other people are using it to learn things, for their homework and their relationships,” she says.

Viner’s team didn’t see the same pattern in boys. More frequent social media use does seem to be linked to more psychological distress in boys, but doesn’t seem to impact their happiness or satisfaction with life.

The link between social media use and psychological distress in boys was partly explained by cyberbullying, sleep and exercise, but not completely. “We can’t really understand what this difference by sex is about,” says Nicholls. The findings won’t hold true for all girls and boys, either, she says. “These are generalisations – there are vulnerable boys and there are more resilient girls.”

In the meantime, Viner and Nicholls recommend that concerned parents try not to worry about how much time their teenagers spend on social media. “It’s not that the screens themselves are toxic,” says Viner. Instead, it is important to encourage exercise and sleep – Nicholls recommends 10 hours for teens aged 13 to 16 – and to ask about the content they are viewing online.

Journal reference: The Lancet Child & Adolescent Health, DOI: 10.1016/S2352-4642(19)30186-5