Embrace the London rat race

Naturally, he has already breakfasted. In New York there would be a bun fight for bagels at that hour - here in central London Buchholz is astonished to find the streets almost empty.

In all other respects, though, as a frenetic and stressed city, London can keep pace with the best of them. If, however, you are feeling a little sorry for your overworked self as the nights draw in, as you fish out the black woolly tights and try to avoid a second bout of flu, take consolation from Buchholz's new book, Rush: Why You Need and Love the Rat Race, already a hit in the States.

His thesis began life as an altogether different book. Aghast at the excesses of his own industry, the plastic surgery addiction of the wealthy and the pushiness of Noughties parents, Buchholz began a book with the working title Tail Hunters: How Americans are Chasing Success and Losing their Souls. But during the research he became convinced that contrary to the claims of the billion-dollar happiness industry, "there is no proof that cutting out the frenzy would make us happier".

"Kumbaya does not work," he states. "Sitting around a metaphoric campfire, holding hands and singing communal songs does not make human beings happy. Sweaty, yes. Sooty, perhaps. But not happy."

The evidence is that far from seeing us into an early grave, stress is good for us - not just spiritually, but physically too. Those who live longest tend to be the people "with a little acid and bite to them", Buchholz argues. Far from losing their rough corners as they mellow and age, they remain ferocious and comparatively youthful.

Look at King Rat Rupert Murdoch, 80, who shows no sign of wishing to retire.

In Rush, Buchholz maintains that human beings are not only happier but more successful when they give in to their inner rat and accept that we are "ambitious and hungry". Rats prosper.

In the brain, dopamine, which is transmitted when we feel pleasure, can be released, as he explains, by "eating, having sex or knocking out an opponent in the ring". Rat-racers compete and so self-administer a constant dose of dopamine - "an elixir, a chemical that delivers a rush, a natural high. It makes us feel alert, interested and, well, alive." And it's not just about winning - dopamine is transmitted just by the expectation of pleasure (be it food, sex or victory), so the chase can be as feelgood as the result.

According to Buchholz, being a rat will make you not only happier but thinner too. Look at people dashing past you with their coffees, he suggests: "Yes, they are in a hurry, but people in London and New York weigh less." He draws my attention to the lithe frames of people who constantly tap their feet.

Buchholz also points out the difference between the life-threatening stress of being chased by a very hungry tiger and "good stress", and takes to task the field of "happiness science", which insists society as a whole needs to slow down.

"Our ability to handle stress is a bit like a muscle. A cushy life will kill you," he argues.

He is "all for vacations" but prefers cultural ones with intellectual activity and stresses they should serve to recharge the batteries, not encourage you to daydream about opening a vegan cocktail bar on the beach. Does Buchholz ever switch off? After the Nineties in Washington and the Noughties in New York, he is now based in California which, he points out, "is a beach community, but one soaked in a lot of perspiration. The more interesting and healthier people tend to be the ones who are out there, training for triathalons."

But there is one cloud on his horizon. Buchholz gets regular hate mail from yoga instructors: "I thought they were meant to be calm but perhaps they are not as relaxed as their lotus positions suggest."