Two followed people over time, with both studies finding that spending more time on social media led to unhappiness, while unhappiness did not lead to more social media use. A third randomly assigned participants to give up Facebook for a week versus continuing their usual use. Those who avoided Facebook reported feeling less depressed at the end of the week.
The argument that depression might cause people to spend more time online doesn’t also explain why depression increased so suddenly after 2012. Under that scenario, more teens became depressed for an unknown reason and then started buying smartphones, which doesn’t seem too logical.
What’s lost when we’re plugged in
Even if online time doesn’t directly harm mental health, it could still adversely affect it in indirect ways, especially if time online crowds out time for other activities.
For example, while conducting research for my book on iGen, I found that teens now spend much less time interacting with their friends in person. Interacting with people face to face is one of the deepest wellsprings of human happiness; without it, our moods start to suffer and depression often follows. Feeling socially isolated is also one of the major risk factors for suicide. We found that teens who spent more time than average online and less time than average with friends in person were the most likely to be depressed. Since 2012, that’s what has occurred en masse: Teens have spent less time on activities known to benefit mental health (in-person social interaction) and more time on activities that may harm it (time online).
Teens are also sleeping less, and teens who spend more time on their phones are more likely to not be getting enough sleep. Not sleeping enough is a major risk factor for depression, so if smartphones are causing less sleep, that alone could explain why depression and suicide increased so suddenly.
Depression and suicide have many causes: Genetic predisposition, family environments, bullying and trauma can all play a role. Some teens would experience mental health problems no matter what era they lived in.
But some vulnerable teens who would otherwise not have had mental health issues may have slipped into depression due to too much screen time, not enough face-to-face social interaction, inadequate sleep or a combination of all three.
It might be argued that it’s too soon to recommend less screen time, given that the research isn’t completely definitive. However, the downside to limiting screen time – say, to two hours a day or less – is minimal. In contrast, the downside to doing nothing – given the possible consequences of depression and suicide – seems, to me, quite high.
It’s not too early to think about limiting screen time; let’s hope it’s not too late.