Johann Hari was 18 when he swallowed his first antidepressant.

"The tablet was white and small, and as I swallowed, it felt like a chemical kiss," he said.

It was only after the British author and journalist finished school, and left his home in the United Kingdom to travel the world, that he began to suspect the abiding unhappiness that had periodically overwhelmed him all his life was not in fact normal.

It was the late 1990s, the "Age of Prozac", and depression and its chemical cure were everywhere.

After sobbing on the Matterhorn and breaking down in Kafka's house, Hari had a realisation.

"There is a term for feeling like this. It is a medical condition."

He soon found a doctor who told him that his diffuse sense of unhappiness and despair was the product of depleted serotonin levels.

His depression, the doctor explained, was a brain disease, and a new generation of drugs — Selective Serotonin Reuptake Inhibitors (SSRIs) — would cure him.

He started taking his medication and, for a time, found relief. But it was short lived. The sadness just kept creeping back.

Each time his medication was increased and, with it, the zealotry of his belief in the cause of his disease and the efficacy of the cure.

"I liked this story. It made sense to me," he said.

But a decade later, a depressed, overweight and anxious Hari felt unable to any longer avoid the contradictions, inconsistencies and glaring inadequacy of that story.

"There were two mysteries hanging over me. One was, 'Why was I still depressed?' The second mystery, the much more important one to me, 'Why are so many people in our culture, becoming so depressed and so anxious?'"

His quest for answers to these questions drove him to research and write a book examining "the real causes of depression and the unexpected solutions".

A global crisis

Hari is not alone, neither in his depression nor his embrace of a chemical cure.

Depression is a condition that only last century afflicted a tiny fraction of the population, but by 2017 the World Health Organisation had declared the leading cause of ill health worldwide.

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In Australia, about 1 million people experience depression every year.

"One in five Americans will take a psychiatric drug in their lifetime. Australia has the second highest level of people taking chemical antidepressants in the world," Hari said.

Yet we are told the "depression epidemic" is only getting worse.

Hari argues antidepressants offer temporary relief to the melancholy and malaise of urban populations, with the underlying cause remaining untreated.

"It's not solving the problem for most people, it's not lifting most people out of not feeling good, which is why we need to have a much deeper conversation about why we're feeling so bad, why those reasons have been increasing and expanding the menu of options so we can deal with these deeper problems," he said.

A bio-psychosocial problem

Psychiatrist and Professor of Youth Mental Health at The University of Melbourne Patrick McGorry agrees that where depression and anxiety are concerned we have narrowed our attention.

"Hari is trying to work out what is driving this level of depression in our society," Professor McGorry said.

"It is a bio-psychosocial problem; there are biological factors and psychological and social factors. What Hari is talking about are the social drivers of depression."

The reasons why the "serotonin theory" and its chemical cure had such immediate and universal purchase are complex.

Both Hari and Professor McGorry agree the pharmaceutical industry played a role.

"It's good to challenge how the drug companies and the DSM and the FDA oversimplify not just depression, but all mental disorders," Professor McGorry said.

"They try to reduce them and American psychiatry is really responsible for that; they turned away from psychoanalysis to biological psychiatry and regarded everything as just a brain disease."

Hari says he is not on a crusade against antidepressants, big pharma or psychiatry.

Nor is he suggesting everyone should stop taking SSRIs, benzodiazepines or any other medication they have been prescribed.

Professor McGorry cautions against dismissing the benefits altogether.

"There are people who are very severely depressed and I believe, if you look at all the evidence, there is absolutely no doubt that antidepressants are lifesaving for them," he said.

Nine causes

Both Hari and Professor McGorry suggest we need to widen our attention, to view depression as the World Health Organisation put it, as "socially produced".

"There is scientific evidence for nine causes of depression and anxiety, none of which can be described as just a chemical imbalance in the brain," Hari said.

Two of those causes are biological; the other seven have more to do with the social and cultural world in which we are embedded and from which so many of us feel alienated.

"Everyone has basic needs for food, water, shelter, clean air. There's equally strong evidence that we have natural psychological needs. You need to feel you belong," Hari said.

Those needs, he argues, are not being met.

He points to research by Australian social researcher and sociologist Hugh Mackay that has revealed an explosion in loneliness over the past 50 years.

Mr Mackay argues "the biggest contributor is social fragmentation".

As the traditional bonds of social life dissolve, as community and interdependence give way to alienation and anomie, we have found ourselves living in a state of dangerous isolation.

"You aren't a machine," Hari said.

"You are an animal whose needs are not being met. You need to have a community. You need to have meaningful values. You need to have meaningful work. You need the natural world. You need to feel you are respected. You need a secure future. You need connections to all these things."

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