The Anxious Generation

The claim

Jonathan Haidt is a social psychologist at New York University. With the researcher Zach Rausch, he spent several years assembling data on adolescent mental health across many countries, and in March 2024 he published The Anxious Generation. Its claim is that the rapid rise in anxiety, depression, self-harm and suicide among adolescents in the United States, Britain, Canada and other countries, beginning around 2012, was caused in large part by a change in childhood that took place between about 2010 and 2015.

He calls the change the great rewiring. Before it, children grew up in what he calls a play-based childhood, with time spent in unsupervised play, physical risk and face-to-face friendship. After it, they grew up in a phone-based childhood, in which smartphones with front-facing cameras, high-speed internet and social media platforms took up much of their time. The shift was compounded, Haidt argues, by a parallel trend toward overprotection in the physical world, which reduced children’s independence just as their virtual lives expanded. He summarises it as overprotecting children in the real world and underprotecting them online.

How the case is built

The book begins with the data. Haidt presents charts showing sharp rises in adolescent depression, anxiety, emergency room visits for self-harm and suicide rates, especially among girls, starting around 2012, in several countries. He argues that the timing, coinciding with the spread of smartphones and the shift of social life to platforms such as Instagram, points to a common cause.

He then proposes four foundational harms. Social deprivation: time with friends in person fell sharply as time online rose. Sleep deprivation: phones in bedrooms reduced sleep. Attention fragmentation: constant notifications made sustained concentration hard. And addiction: platforms were designed with variable rewards that encourage compulsive use.

He describes different effects on girls and boys. For girls, he argues, social media intensified social comparison, perfectionism and relational aggression, especially on visual platforms. For boys, he argues, the main shift was withdrawal into video games and online worlds, with fewer real-world challenges and relationships.

He draws on experimental studies, in which people who reduced social media use reported better well-being, and on natural experiments, such as the arrival of high-speed internet in different regions at different times.

Finally, he proposes four norms that he argues would reverse much of the harm if adopted collectively: no smartphones before high school, no social media before sixteen, phone-free schools, and far more independence, free play and responsibility in the real world. He stresses that these work best as collective action, because individual families who hold out face social costs when their children’s friends are all online.

What it takes for granted

The central assumption is causal. Haidt accepts that the correlations between social media use and poor mental health in large surveys are modest, but argues that together with the timing, the experiments and the mechanisms, they support a causal story. Other researchers read the same evidence differently. The psychologist Candice Odgers, reviewing the book in Nature in 2024, argued that it confused correlation with causation, that most studies find small or mixed associations, and that the focus on technology could distract from other causes, including economic stress and other social problems. Haidt replied at length, arguing that the experimental and quasi-experimental evidence, and reports from adolescents themselves, support his account. The debate continues among researchers.

The book also assumes that collective norms can be changed quickly, and that the four it proposes would have the effects predicted. Much of that remains to be tested.

Since it was published

The book became a bestseller, and its proposals spread faster than many researchers expected. Phone-free school policies were adopted in many American states and in other countries. Australia passed a law barring under-sixteens from holding accounts on major social media platforms, which took effect in December 2025, and several other countries, including Britain and France, announced or proposed age limits of their own. A Pew Research Center survey in mid-2026 found that a majority of American adults supported banning social media for children under sixteen. Early studies of school phone bans have produced mixed results on outcomes such as test scores, and the effects of the new age limits on mental health are not yet known. The site’s essay Everyone You Know, and Everyone You Don’t follows the design of the platforms at the centre of the debate.

What it asks of someone deciding

For people who build products, the book asks who is using them and what the design does to the most vulnerable users. Features that are harmless for adults may affect adolescents very differently. The site’s idea page Wanting What We Want to Want asks whether users would endorse their own patterns of use on reflection.

For parents and schools, it asks whether a choice should be made individually or together. Haidt’s argument that the problem is a collective action trap, in which no family wants to be the only one to hold out, applies to many situations where the costs of being first are high.

And for anyone weighing evidence, the book and its critics show how a serious problem can be real while its causes remain disputed. Acting under that uncertainty, and continuing to measure the results, is part of good decision-making.