Inequality breeds stress and anxiety. No wonder so many Britons are suffering | Richard Wilkinson and Kate Pickett

In equal societies, citizens trust each other and contribute to their community. This goes into reverse in countries like ours

The gap between image and reality yawns ever wider. Our rich society is full of people presenting happy smiling faces both in person and online, but when the Mental Health Foundation commissioned a large survey last year, it found that 74% of adults were so stressed they felt overwhelmed or unable to cope. Almost a third had had suicidal thoughts and 16% had self-harmed at some time in their lives. The figures were higher for women than men, and substantially higher for young adults than for older age groups. And rather than getting better, the long-term trends in anxiety and mental illness are upwards.

For a society that believes happiness is a product of high incomes and consumption, these figures are baffling. However, studies of people who are most into our consumerist culture have found that they are the least happy, the most insecure and often suffer poor mental health.

Related: The psychological effects of inequality - Science Weekly podcast

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