"Have Smartphones Destroyed a Generation?" wondered celebrated sociologist Jean Twenge in The Atlantic earlier this year. It's a scary headline, so scary in fact that you're likely to ask: is Twenge just being alarmist? Having a kid on Snapchat all day is certainly annoying, but is it really such a serious problem?

It's a sensible question to ask. After all, adults have been shaking their grumpy, wrinkled fists at "kids these days" since time immemorial, but if you are among the skeptics, I have bad news for you. Research attesting to the harm excess screen time does to kids is starting to pile up, and Twenge is right. Much of it is pretty alarming.

Massive study, bleak conclusions

Take a recent study by Twenge herself highlighted in PsyBlog as evidence. The study takes as its starting point a frightening statistic - the suicide rate for teen girls has doubled in the last ten years or so. This is also the decade that smartphones became ubiquitous. Could these two facts be related?

To try to figure this out, the researchers looked at two massive data sets - one from an ongoing study that tracks teens' screen time usage in eighth, tenth and twelfth grade and another from the CDC on risky teen behaviors. Together they contained information on half a million young people.

Twenge's team sifted through all this information, comparing the quantity of time teens spend staring at screens with reported jumps in depression symptoms and risk factors for suicide. They came to a bleak conclusion.

"The study showed that those who spent more than five hours per day on electronic devices had almost twice the suicidal tendencies of those spent an hour or less per day," reports PsyBlog.

"These increases in mental health issues among teens are very alarming. Teens are telling us they are struggling, and we need to take that very seriously," Twenge commented. 

Criticism of Twenge's work

Those numbers are indeed worrying, but other researchers have suggested the picture might not be as black as Twenge paints it. These are only correlations after all - screen time and depression and suicide seem to go together - it could be that depressed kids are simply more likely to stay shut in with their gadgets.

"It is not uncommon for people who are depressed to socially isolate," Lisa Pont, a therapist at the Centre for Addiction and Mental Health in Toronto, told Motherboard, for instance. "Once isolated, people may be inclined to go online to distract from painful emotions, reduce boredom or meet needs for some kind of social connection."

Still, that's not entirely comforting for parents of screen-obsessed kids. It's just as worrying to think your kid is always online because they're depressed and isolated as it is to think your kid is depressed and isolated because they're always online.

Recommendations for parents

So what should you do to protect your family from the trends suggested by this study? Twenge (and a whole lot of tech moguls) suggest limiting teens' screen time to just an hour or two a day. She also points out that social media may be more corrosive to mental health than, say, gaming (which might also explain why girls, who tend to spend relatively more time on social networks, may be more adversely affected by the rise of smartphones).

Also, Twenge's data suggests that good old-fashioned analog activities might protect kids from the negative consequences of screens. The study also showed that sports, exercise, doing homework, and talking to people in real life were linked with a reduced risk of suicide and depression.

So if you're concerned about the impact of screens on your kid's mental health, try kicking them out into the real world. Though they'll probably whine and complain, these findings suggest more contact with reality will do them good.