Just How Toxic Is Screen Time?

Jean Twenge and her colleagues have a pretty dire story to tell you. It’s all about the toxic effects of screen time on our youth:

In just the five years between 2010 and 2015, the number of U.S. teens who felt useless and joyless – classic symptoms of depression – surged 33 percent in large national surveys. Teen suicide attempts increased 23 percent. Even more troubling, the number of 13- to 18-year-olds who committed suicide jumped 31 percent.

All signs point to the screen.

Damning Correlations

Twenge’s research, newly published in Clinical Psychological Science, deals with the effects of screen time on mental health.

Elsewhere, evidence is growing to suggest an effect on metabolic health. It prompted a new consensus statement from the European Academy of Pediatrics and the European Childhood Obesity Group. These groups describe a “strong link” between screen exposure and obesity. Their concerns are broad. They describe issues with pervasive food advertising on every type of screen.

The solution is simple, they say. No unsupervised screen time before the age of four. After that, no more than 90 minutes of screen time per day. Twenge has similar recommendations. She grants that the evidence is not yet definitive. But, she says, the downside is minimal. And the downside of doing nothing seems quite high to her.

Two Little Problems: Causality and Effective Solutions

So far, the evidence is quite distressing. Overdosing on screen time may indeed be toxic for both physical and mental health. Unfortunately, all of this concern springs from data that shows a correlation – not a cause and effect. Twenge concedes that reverse causality might be the issue. In other words, depression might be causing youth to spend more time online.

Likewise, the data linking obesity and screen time are all observational. And unfortunately, we have little or no evidence that reducing screen time has an effect on BMI. Adequate studies are simply lacking.

More Science and Less Puffery, Please

The presumption is reasonable. Excessive screen time might indeed be a dire threat to the health of generations to come. But presumptions alone are not good enough for making health policy.

Ranting about the dangers of screen time might not be enough. Guidance that has an effect is what we need. We must collect hard data on interventions that work. That’s the best way to make the case and make a difference.

Click here and here for more from Twenge. For the new consensus from Europe, click here. You can find more on the relationship between screen time and childhood obesity here, here, and here.

Sharing Screen Time, photograph © MollySVH / flickr

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November 25, 2017