Itsu is a Japanese-inspired chain of some 40 takeaways and a brace of proper restaurants that are scattered across London’s financial district with a few outliers, including one in Oxford. Itsu – which is a Japanese prefix meaning “when” – was founded by Julian Metcalfe, who is also responsible for Pret A Manger, so you get the semantic synonymy.

I ate in a branch of Itsu near St Paul’s a couple of weeks agoD and for some perverse reason I so enjoyed the experience that I returned to see whether I had been suffering from a hallucination: the decor had seemed so pleasing, the service so light-touch and the food so deliquescent.

I had been hallucinating – on second pass, Itsu was just another fast-food joint with a shtick devised to part office porkers from their readies.

I suppose it is interesting to ruminate on this strange fact along with one’s Itsu salad box: that over the past 15 years or so, simulacrums of Japanese eateries have come increasingly to dominate British high streets, much as replicants of human beings will doubtless vault the boulevards of Los Angeles come the end of this decade. In City of Quartz, his fine work on the psychogeography of LA, Mike Davis hypothesises that the Asiatic hordes teeming through Ridley Scott’s Blade Runner were a sublimation of the anxiety felt by Hollywood during the early 1980s as more and more prime downtown real estate was snaffled up by the Japanese. Fair enough, yet this doesn’t really explain why British quants and financial traders are now so enamoured of rice noodle soup and sushi selections – unless, that is, they believe that by eating Japanese they will magically ward off the deflation that has bitten down on the once-tiger economy for the past 25 years.

The Itsu philosophy (if we can sully the word) is to respond to “years of listening and reacting to customer feedback” by “creating a low-calorie menu for the upbeat and the active”. But am I alone in detecting a contradiction here? The last thing the active and upbeat require is “butterfly-light, low-fat, nutritsu food”; I mean, if you’re properly active you can get away with more or less limitless stodge. As for the grim coinage “nutritsu”, this is of a piece with other bits of babyish signage stuck up in Itsu – ask not for a noodle pot but a “noodle potsu”, and (most yucky this) you might like to sluice it down with an “itea”. Combine with the life-size sepia shots of etiolated Japanese maidens in itsu-bitsy bikinis that adorn the walls and you get the picture: Itsu is aimed not so much at the high, male end of the City feeding chain but at female secretaries and keyboard rifflers whose sedentary drudging is – they quite reasonably worry – turning them to sludge.

On beige-vinyl-covered stools held aloft by mirror-shiny aluminium poles, with one’s Hello Kitty handbag shackled to the underside of the table by a purpose-designed strap (handy, that), you can squirt soy sauce from one of those dear little individual plastic bottles into one of those dear little individual plastic trays, then mix in the wasabi with the tip of your chopstick. Mm, it’s all so . . . diminutive. On reflection, I think it is this aspect of Japanese culture that most appeals to us at an unconscious level: the saccharine infantilising of the bitter pill of machine ordered conformity. We may have to work all the hours Mammon sends, but at least we can have our lunch break in cute surroundings, our fair cheeks brushed by the wings of the Itsu butterfly logo.

In fact, the food at Itsu is perfectly all right. Even close to closing time on a gloomy October evening the salad still had some bounce in it and the sushi some bite. As for the miso soup – which Metcalfe has insinuated on to the shelves at Sainsbury’s – it was a wholesome mixture and looked, as good miso soup should, like the beginnings of an attempt to see if life can be synthesised in a laboratory.

In a way, I find this most disturbing of all: that food should be subject to the most ruthless commoditisation under late capitalism is only to be expected, but that we should for one second allow ourselves to enjoy it is a miserable and gut-wrenching experience. Every time I find myself savouring under such circumstances, I double-take, remembering Winston Smith looking up from the table at the Chestnut Tree Café to see the implacable face of Julian Metcalfe – sorry, I mean “Big Brother” – staring down at him, and returning that dictatorial gaze with . . . love.