For roughly two hundred years, missing home could kill you. Not in a poetic, broken-hearted sort of way. Doctors logged it as an actual cause of death.

The word nostalgia was invented in 1688 by a Swiss medical student called Johannes Hofer, who welded together two Greek words: nostos, meaning homecoming, and algos, meaning pain. He was trying to name something he kept spotting in Swiss mercenaries posted far from the Alps. Young men who went pale, lost their appetite, ran fevers, developed racing hearts, and occasionally faded away entirely. The official diagnosis was that they missed home too much.

I have a modest personal stake in all this. I spent my teenage years at a boarding school in Australia, a very long flight from where I grew up. Nobody suggested I was terminally ill, mercifully. But had you told a seventeenth-century physician that a homesick boy was slowly unravelling over the memory of a kitchen half a world away, he’d have nodded solemnly and reached for the leeches.

When missing home was a medical emergency

Hofer’s idea had legs. For two centuries, physicians across Europe and America treated nostalgia as a serious illness, quarrelled endlessly about how to cure it, and wrote it onto death certificates.

Their proposed causes were magnificent. Hofer blamed “animal spirits” rattling around the brain, so fixated on home that the body forgot to keep the lights on. A Zurich naturalist had another go and pinned it on air pressure, reckoning that mountain folk got ill at lower altitudes because their blood thickened. Others blamed cowbells and old herding songs, the sort of tunes that apparently sent Swiss soldiers into a decline the moment they heard them.

The cures were worse than the tunes. Bloodletting. Purging. The occasional threat of being buried alive, which was less a treatment and more a motivational technique. The only reliable fix anyone could agree on was going home.

And this was just accepted medicine for a very long time. Even into the twentieth century, nostalgia lingered in the manuals as a psychiatric problem, a species of melancholy or maladjustment, the kind of thing a healthy adult was meant to outgrow.

The psychologists who let nostalgia off the hook

Then, in the mid-2000s, a group of researchers at the University of Southampton decided to actually test the thing rather than assume it was a defect.

Constantine Sedikides and Tim Wildschut led the charge. Their argument was blunt. Nostalgia had spent centuries filed under “disease” and “disorder”, and almost nobody had bothered to check whether that filing was correct. So they checked.

What they found flipped the whole story. Nostalgia turned out to be a mostly positive emotion, one that most people feel often. In their early work, nearly eight in ten students reported getting nostalgic at least once a week. So much for a rare affliction of the homesick and the doomed. It was a normal, frequent, largely pleasant part of being a person.

More interesting was the question of what nostalgia is actually for.

What a good wallow actually does

When the Southampton team looked at what people were nostalgic about, it was rarely objects or achievements. It was people. Weddings, childhoods, kitchens full of relatives, the friend you drifted away from. Nostalgia is a deeply social emotion, and reliving those moments makes people feel more connected, more loved, and less alone.

That last part matters more than it sounds. A study led by Xinyue Zhou with the Southampton group found that loneliness actually triggers nostalgia, and that the nostalgia then pushes back, quietly restoring your sense that there are people who care about you. It works like a built-in coping mechanism, reminding you that you belong to someone.

From there the benefits stack up. Nostalgia has been shown to boost optimism, oddly enough, nudging people to look forward rather than only back. It also seems to make life feel more meaningful. One study traced the mechanism step by step: nostalgia makes you feel connected to others, that connection makes you feel like a single continuous person across your whole life, and that sense of continuity is what makes things feel like they mean something.

So the very thing that seventeenth-century doctors tried to bleed out of soldiers is, it turns out, one of the tools your brain uses to keep you standing.

The pandemic gave us a giant test

If you wanted a real-world experiment, we just ran an enormous one on ourselves.

During the COVID lockdowns, the same researchers surveyed thousands of people across China, the United States and the United Kingdom. Loneliness was everywhere, for obvious reasons. But the people who leaned into nostalgia reported more happiness, and that happiness took the edge off the loneliness.

I sold my restaurants during that same stretch, a small chain I’d poured years into, and I spent a good part of that first strange lockdown scrolling through old photos of full dining rooms and shambolic staff Christmas parties. At the time I assumed I was just moping. It seems I was self-medicating, and the medicine was working.

How to be nostalgic without getting stuck

Here is the catch, because there’s always a catch.

Nostalgia is a bridge, not a house. The research is clear that remembering good times with people is restorative. It is far less clear that moving into the past permanently and refusing to come out does you any favours. There’s a real difference between visiting an old memory to feel connected and using it to hide from your actual life.

So a few practical notes, from someone who has done both.

Reach for people, not things. The version of nostalgia that helps is the one full of faces. If your fondest memories are mostly about stuff you owned or trophies you won, dig a little deeper for the humans who were standing next to you at the time.

Let it point forwards. If an old memory makes you want to phone someone, phone them. That is nostalgia doing its actual job, which is to remind you that connection is available now, not just fondly remembered.

And notice when it curdles. If looking back leaves you convinced that everything good is behind you, that isn’t nostalgia being helpful anymore. That’s rumination wearing nostalgia’s coat, and it’s worth quietly stepping away from.

Hofer got one thing right, for what it’s worth. He understood that the mind’s pull toward home is strong enough to reshape the body. He simply had the sign backwards: what he took for a wound is really the part of you that remembers you were loved, and gently insists you still are.

Not bad for a disease.