Most recently, in 2017, Twenge published a pop-science book laying out her central argument that teens and young adults coming of age are especially lonely and disconnected, thanks in part to the growing abundance of social media and devices like smartphones.
Twenge’s book and work had has its detractors, who argue that her theory is supported by cherry-picked and weak evidence, or that other factors aside from smartphones could be the real culprit behind a legitimate rise in teen depression.
Between those years, they tracked the rate of reported episodes of major depression and serious psychological distress, measured by how people responded to questions such as whether they ever felt “so sad or depressed that nothing could cheer them up.”
A similar pattern held true for episodes of major depression and suicide-related outcomes: Teens and young adults had higher rates of depression in 2017 than they did a decade before, while the rate of depression for most age groups over 30 was actually lower in 2017 compared to 2009 (seniors were the exception).
Regardless of the exact causes, it’s known that depressed and suicidal teens are more likely to suffer as adults, so this large wave of depression among the young could cause ripples years or even decades down the road.