Is social media causing teen depression?

The honest answer is plausibly a contributor, not a proven sole cause. The timing is the strongest part of the case: smartphone ownership went majority around 2012, and teen distress curves bend at the same moment. Jonathan Haidt and Jean Twenge build the full argument from there.

But timing is a correlation, and the measured effect is small. The phone may be one ingredient among several (lost play, academic pressure, sleep loss) rather than the single switch that flipped. More: what's actually causing it.

A robust correlation, a contested cause, and small effect sizes. Amy Orben and Andrew Przybylski analyzed data from hundreds of thousands of teens and found digital-technology use explained at most about 0.4% of the variation in well-being: a real link, but a tiny one.

Candice Odgers, reviewing Haidt's case in Nature, made the core objection: the correlations are genuine, but no study has shown harm at the scale the strong claims assert. There's also reverse causation to reckon with: struggling teens may reach for the phone because they're hurting, which makes the screen look like the cause of an ache it was used to soothe.

That's the leading version of the case. Haidt and Twenge argue girls are hit harder through appearance comparison and relational aggression on visual, public platforms, while boys' screen time runs more through gaming. Girls' depression rates do run two to three times boys'.

One honest caveat: "worse for girls" depends on what you measure. Girls carry more of the internalizing distress (depression, anxiety), but boys' distress more often shows up as disengagement, and boys die by suicide at far higher rates. The full picture, matched by sex, is more even, and more sobering, than the depression numbers alone suggest.