The Anxious Generation

Haidt provides parents’ accounts of how smartphones, social media, and video games have transformed childhood for the worse. Many parents describe constant battles over screen time, struggling to enforce limits without isolating their children socially. Others share more troubling stories—children who once thrived becoming moody, withdrawn, or depressed. He provides two detailed examples: a teenage girl whose mental health declined as she used Instagram, leading to self-harm threats when her parents tried to restrict her access, and a boy with mild autism who became aggressive and emotionally volatile after excessive video game use. In both cases, parents found that removing digital access led to temporary improvement, yet they felt powerless to maintain these restrictions in a world where all their children’s peers remained online. This sense of entrapment is widespread—most parents do not want their children to grow up in a phone-dominated world, yet resisting the norm risks social exclusion.

Haidt argues that these anecdotal experiences reflect a much broader crisis. Beginning in the early 2010s, rates of adolescent anxiety, depression, and self-harm surged. Prior to that, there were no signs of an impending mental health disaster; adolescent well-being had remained stable throughout the 2000s. But something changed between 2010 and 2015, leading to a sudden, large-scale decline in mental health among Gen Z (and some late millennials), a trend not observed in older generations. Using data from the U.S. National Survey on Drug Use and Health, Haidt highlights a dramatic increase in depression: major depressive episodes nearly tripled for teenage girls and doubled for boys. These increases were not limited to any particular demographic—adolescents of all races and economic backgrounds were affected.

Haidt then examines the nature of this crisis. The surge primarily involves internalizing disorders, which include anxiety and depression. These conditions manifest as emotional distress turned inward, leading to rumination, withdrawal, and social isolation. Historically, girls have been more prone to internalizing disorders, while boys have exhibited more externalizing disorders—problems like aggression, rule-breaking, and impulsivity. However, since the early 2010s, internalizing disorders have sharply increased for both sexes, while externalizing disorders have declined. On college campuses, where data is more easily tracked, depression and anxiety diagnoses have risen far more than other mental health issues, suggesting a fundamental shift in adolescent well-being.

Anxiety, Haidt explains, differs from fear. While fear is a response to an immediate threat, anxiety is the anticipation of future danger. In evolutionary terms, fear is essential for survival, triggering immediate physical and cognitive responses to threats. Anxiety, when moderate, can also be beneficial and help people prepare for challenges. However, excessive or chronic anxiety leads to distress, exhaustion, and cognitive distortions, such as catastrophizing and black-and-white thinking. The second most common disorder, depression, often coexists with anxiety and is characterized by deep sadness, apathy, and a sense of hopelessness. Depression is particularly linked to social disconnection, creating a vicious cycle: loneliness increases depression, and depression makes it harder to seek social connection.

Skeptics initially questioned whether the rising rates of anxiety and depression reflected actual increases in suffering or merely greater willingness to self-report mental illness. Haidt refutes this argument by pointing to behavioral evidence. Hospital visits for self-harm among preteen and teen girls nearly tripled from 2010 to 2020, and emergency psychiatric admissions also surged. Suicide rates for adolescent girls began rising in 2008 and spiked dramatically in the early 2010s, indicating a real, measurable increase in distress. These trends confirm that the crisis is not simply a matter of increased awareness or self-diagnosis—it is an objective shift in adolescent well-being.

Haidt identifies the smartphone as the primary cause of this mental health crisis. The rise of smartphones and social media unfolded in two technological waves. The first, in the 1990s and early 2000s, saw the spread of personal computers and the internet, which had no apparent negative impact on adolescent mental health. The second wave, beginning around 2010, introduced the smartphone and algorithm-driven social media, profoundly altering how adolescents interacted with the world. Unlike early cell phones, which were mainly used for calls and texts, smartphones provided continuous internet access, social media apps, and immersive digital experiences, fundamentally changing how young people were socialized.

For girls, this transformation revolved around social media, particularly Instagram. When Facebook acquired Instagram in 2012, its user base expanded rapidly. The combination of front-facing cameras, filters, and algorithmic amplification intensified social comparison. Girls became immersed in a digital world where appearance and social validation determined their status. The pressure to curate an idealized online persona, coupled with the risk of public humiliation or exclusion, made social media a source of constant stress. Meanwhile, boys became more engaged in immersive online experiences, including multiplayer gaming, YouTube, Reddit, and pornography. These platforms offered intense stimulation and escape, often at the cost of real-world social interactions. The cumulative effect was a decline in face-to-face engagement and physical activity, which are crucial for healthy adolescent development.

Next, Haidt takes a moment to dismiss some alternative explanations for the mental health crisis. Some argue that Gen Z’s anxiety stems from real-world stressors such as climate change, political instability, and economic uncertainty. However, historical evidence contradicts this view. Past generations also faced existential threats, from World War II to the Cold War, yet these crises often fostered resilience and social cohesion. Haidt suggests that what makes Gen Z different is not the presence of global problems, but the way they experience them—alone, through the highly emotional, algorithmically driven lens of social media.

Notably, the mental health crisis is not just an American phenomenon. Haidt presents data from Canada, the UK, Australia, and the Nordic countries, all showing the same pattern: a sharp increase in adolescent depression and anxiety beginning in the early 2010s. Even global surveys of school-aged children reveal rising loneliness and social disconnection. This suggests that the crisis was not triggered by any single national event, but rather by a worldwide technological shift.

Haidt describes the early 2010s as the period of “The Great Rewiring of Childhood.” The shift from a play-based to a phone-based childhood fundamentally altered social development. The first generation to grow up fully immersed in smartphones and social media—the early members of Gen Z—became more anxious, depressed, self-harming, and suicidal. The crisis hit girls hardest, but boys were not spared. The key question, Haidt says, is not just why this happened, but how a phone-based childhood disrupted child development.