Perhaps depressives have an instinct for each other. Why else, when Johann Hari was at the centre of a furore over plagiarism that led to him losing his column on The Independent seven years ago, did I decide to drop him a line? I barely knew him and rarely read his paper, but something told me to offer a few words of encouragement that it is possible to survive media storms and emerge stronger.

Sure enough, in his reply he confided that he was prone to severe depression, something that was not exactly being helped by the onslaught on his reputation. As with most media frenzies, I assumed it to be overblown, and assumed also that it would eventually blow over, as indeed it did. We have corresponded intermittently on our shared keenness to destigmatise mental illness ever since.

It was his previous book on drugs, Chasing the Scream, that alerted me to the depth and breadth of his journalistic abilities. Some books have changed my opinion on an issue slightly. This one changed my outlook completely. My attitudes, formed over a lifetime spent viewing illegal drugs as bad, drug dealers as worse, and the issue as one best dealt with by harsh laws vigorously enforced (tough on crime, not the causes of crime, you might say), were fundamentally challenged by his reportage and analysis. He travelled the world to look at the drugs trade from every angle imaginable and concluded, convincingly, that the ‘war on drugs’ was failing and a totally new approach was needed. The book, deservedly, became a bestseller and helped Hari rebuild his reputation, particularly in the United States.

Indeed, any criticism I have of his new book on depression is less about his main thesis, and the nicely structured unfolding of it, than the fact that centres are ‘centers’ and programmes are ‘programs’. He also has a strange fondness for the words ‘thrum’ and ‘thrumming’. I spotted, too, the occasional split infinitive, which always sets my teeth on edge, but I recognise that this is a minority irritation and these are minor quibbles. None of them detracts from the enjoyment and enlightenment I experienced reading a book very much in the tradition of Hari’s first. He takes a big, controversial subject, surrounded by strong opinions and taboos, covers it on a global canvas through diligent research and extensive human interaction, and reaches a clear and broadly compelling conclusion.

I was an easier door for him to be pushing at this time. I know a lot more about depression, which I have suffered from on and off for several decades, than about illegal drugs, which I have never taken. At the time I was reading Lost Connections, I was working on a documentary for the BBC about depression, so we were talking to some of the same people. We were also asking the same question: whether antidepressants, of which we both have considerable experience, good and bad, are the right way to treat the illness we share.

He is clear that in the main they are not, though he is careful not to be dismissive of the good they can do for some people in some circumstances. But if there is one driving thought going through the book, it is that depression is not caused by imperfections in the brain, to be cured by a pill, but by imperfections in our lives and the way we live them. It is not serotonin (lack of) that needs fixing, but society (lack of). So far, so touchy-feely. But there is much in here that is practical: examples of people, groups and whole communities that have taken a different approach, and with some success. A good book tells you things you didn’t know. I didn’t know that the city of São Paulo banned billboard advertising, for example, its leaders fearing that rampant materialism was harming the wellbeing of the people there. The experiment led to a downturn in depression and anxiety.

Hari’s loathing of advertising comes through strongly, as does his loathing of junk food, to which he was once addicted: ‘Materialism is KFC for the soul.’ As junk food is distorting our bodies, he argues, junk values are distorting our minds. In other words, as societies we are losing sight of – and so people are becoming disconnected from – the things that really matter. He goes through those various disconnections: disconnection from work, or at least work that people find genuinely fulfilling; disconnection from other people, creating a loneliness epidemic; disconnection from non-junk values; disconnection from childhood trauma (it was only when he acknowledged and confronted the abuse he endured as a child that he began to sense a possible path to recovery); disconnection from status and respect, about which he draws lessons from the wider animal kingdom; disconnection from the natural world; disconnection from a hopeful and secure future (zero hours contracts cop it here).

Having set up the problems, he searches for reconnection solutions, visiting places as varied as Elkhart-LaGrange in Indiana, home of an Amish community, a Canadian region giving everyone a universal basic income to relieve the financial insecurity that can both cause and fuel depression, a cooperative bike shop in Baltimore set up by workers angry at the way their boss was treating them, and an east London doctors’ surgery that focuses on ‘social prescribing’, treating depression by linking the patient to volunteer groups rather than with pills. Gardening groups seem to work especially well.

Depression, he argues, is not a chemical imbalance of the brain. It is ‘grief for the connections we have lost’, and he makes a very strong case that once we see ‘sanity in this sadness’, we can start to rediscover them and so live happier, healthier lives. The morning after I finished the book, I still popped my 100 milligrams of sertraline, something I have done every day for several years, previous attempts to come off antidepressants having invariably led to a major crash within months. But if and when I do come off the pills again, which I fancy I will, Hari’s latest excellent contribution to public debate will be part of my armoury.