Lost Connections

Hari argues that depression and anxiety are caused predominantly by social and environmental conditions rather than by brain chemistry, and identifies nine causes he groups as disconnections: from meaningful work, from other people, from meaningful values, from childhood trauma, from status and respect, from the natural world, from a hopeful future, and two genuine biological contributors in genes and brain changes.

His attack on the chemical imbalance account draws on Irving Kirsch's meta-analyses of antidepressant trials including unpublished data, which found the difference between drug and placebo small on average, and on the argument that the serotonin hypothesis was never well supported and has been abandoned by researchers while remaining in public understanding.

His evidence includes Michael Marmot's Whitehall studies linking control at work to health outcomes, work on loneliness by John Cacioppo, the Kaiser Permanente adverse childhood experiences study, and reporting on specific interventions including a Berlin housing campaign, a Baltimore social prescribing programme and a Kotti community response. His proposed solutions are social rather than individual, including reconnection to community, meaningful work, and addressing material insecurity.

The book has been heavily criticised by psychiatrists. Hari understates the evidence for antidepressant efficacy in severe depression, presents the chemical imbalance account as a straw man that clinicians had already abandoned, and his framing risks discouraging people from treatment that works for them. Hari also has a documented history of fabrication and plagiarism in his earlier journalism, which he acknowledges, and readers should verify claims independently. The social determinants he identifies are real and well supported in the literature he draws on.