Today’s teens and tweens have built up an impressive amount of daily screen time. Figures put it at between six to eight hours a day for 11-15 year-olds, and that’s not including time spent on a computer for homework. In fact, even the average UK adult spends more time looking at a screen than they do sleeping, according to one analysis.
It starts early. A third of UK children have access to a tablet before they are four.
It’s no surprise, then, that today’s youngest generations will be exposed to (and no-doubt join) the social networks their elders already use. Snapchat, for instance, is extremely popular among teens. One December 2017 survey found that 70% of US teens aged 13-18 use it. Most of those questioned also have an Instagram account. Figures are similar in the UK.
Over three billion of us are now registered on a social network, many of us on more than one. We spend a lot of time there - US adults spend an average of 2-3 hours a day.
This trend is now exposing some worrying results and, staying hot on the heels of social-media’s popularity, researchers are interested in the impact it is having on many aspects of our health, including sleep, the importance of which is currently gaining unprecedented attention.
So far it does not look good. We’re now coming to terms with the fact that social media has some clearly negative impacts on our sleep and with that, our mental health.
Ever since the meteoric rise of social media, Brian Primack, director of the Center for Research on Media, Technology and Health at the University of Pittsburgh, has been interested in its impact on society. Along with Jessica Levenson, he examines the relationships between technology and mental health, looking at the good and the bad.
自从社交媒体异军突起以来，匹兹堡大学媒体、技术与健康研究中心主任布莱恩·普利马克（Brian Primack）就一直对其社会影响很感兴趣。他和杰西卡·列文森（Jessica Levenso）一道研究了科技和精神健康之间的关系，包括正面和负面关系。
When considering a link between social media and depression, they expected there to be a dual effect – that social media might sometimes alleviate depression, and sometimes exacerbate it, results which might plot out nicely in a “u-shaped” curve on a graph. However, a survey of almost 2,000 people revealed something much more surprising. There was no curve at all, the line was straight, and in an undesirable direction. Put another way, an increase in social media is associated with an increase in the likelihood of depression, anxiety, and a feeling of social isolation.
“In an objective way, you might say: this person is interacting with friends, passing on smiles and emojis, you might say that person has a lot of social capital, that they are very engaged. But we found those people seem to have more feelings of perceived social isolation,” says Primack.
What is unclear, however, is the exact causal direction: does depression increase social media use, or does social media use increase depression? Primack suggests it could be working both ways, making it even more problematic as “there’s a potential for a vicious cycle". The more depressed a person is the more social media they might then use, which worsens their mental health further.
But there’s another worrying impact. In a September 2017 study of over 1,700 young adults, Primack and colleagues found that when it comes to social media interaction, time of day plays a fundamental role. Engagement during the last 30 minutes before bed was found to be the strongest indicator of a poor night’s sleep. “It was completely independent of the total amount of time of use in the day,” says Primack.
Something about keeping those last 30 minutes tech-free, it seems, is crucial to a restful slumber.
There are several factors that could explain this. A now well-told caution is that the blue light emitted from our screens inhibits our melatonin levels – a chemical that effectively tells us that it’s time to nod off. It could also be possible that social media use increases a person’s anxiety as the day goes on, making it hard to switch off when we finally go to bed. “Then thoughts and feelings come back to haunt us as we try go to sleep,” says Primack. Or a more obvious reason might be that social media is deeply alluring and simply reduces the time we have for sleep.
We know that physical activity helps people sleep better. More screen time is also likely to reduce time spent for physical activity, a link that has been established by research. “It induces more sedentary behaviour during the day. If you have a smart phone in your hand, you won’t be swinging your arms as quickly or moving your legs. If you add that up over six months, you may have a new generation who are not moving as much each day,” says Aric Sigman, an independent lecturer in child health education.
If social media use is exacerbating anxiety and depression, it could then, in turn, impact sleep. If you lay in bed awake comparing yourself to other people’s posts ranging from #feelingblessed, #myperfectlife to air-brushed holiday snaps, you might well believe that your life is somewhat drab in comparison, which could make you feel worse and keep you up.
And so it seems there is a merry-go-round of interrelated issues at play. Social media is linked to increased depression, anxiety and sleep deprivation. And a lack of sleep can both worsen mental health and be a result of metal health issues.
A lack of sleep has other side-effects: it has been linked to an increased risk of heart diseases, diabetes, obesity, poor academic performance, slower reaction times when driving, risky behaviour, increased substance use… the list goes on.
What’s worse is that when it comes to sleep deprivation, it’s usually young people who are most adversely affected. That’s because adolescence is a time of important biological and social changes that are critical to development.
Adolescents also take longer to build up what’s called a “sleep drive” – which is the drive that helps you to fall asleep the longer you have been awake, explains Jessica Levenson, of the University of Pittsburgh School of Medicine. This contributes to teens in particular having a harder time falling asleep at night, she says.
Levenson now worries that social media use, and the literature and research around it, is growing and changing so quickly, that it is difficult to keep up. “It’s our responsibility to explore the impacts, good or bad,” she says. “We are just starting to cover the impact of social media use. Teachers, parents and paediatricians need to be asking teens: how often? When? How do they feel when using it?”
To combat any downsides of social media use, it’s clear that moderation is key. Sigman says we should all ring-fence particular times throughout the day in which we can distance ourselves from our screens, and do the same for children. Parents, he argues, need to have set places in their homes where devices can or cannot be used “so it’s not a fluid situation where social media is bleeding into every part of your life without any buffer zones”. This is especially important as children have not yet developed adequate levels of impulse control to know when is enough, he explains.
Primack agrees. He is not calling for people to stop using social media, but to consider how much – and exactly when in the day – they do so. “The bottom line is, when there is all of this power trying to keep us glued to these sites, that’s going be hard for us to compete with,” he says. He hopes that strong research and engagement management advice, particularly when it comes to no-go social media times, will even the playing field.
As for adults, if you were on your phone before bed last night, and you feel a bit groggy today, it may be in your control to fix it. You may well sleep better if you put your phone away.