You know something’s fishy when, in the space of two months, seven different people tell you that Kate Moss is “fat”. Admittedly, each instance involved a rake-thin stylist or photographer, usually at a foodless fashion party heavy with toxic Veuve Clicquot fumes and cigarette smoke. These are the sorts of people who might once have cast their eyes up and down a size-6 model at a casting and sniffed: “I can only count four of her ribs. Next!” Yet when they told me Moss was fat, it wasn’t with derision. It was with admiration. After 10 years of maple-syrup diets, ashtanga yoga, low-rise jeans and rib-counting, something utterly unexpected has happened. “Fat” is no longer the ultimate fashion insult.

Naturally, with this lot, “fat” is a relative term. Evidence of Moss’s new heft amounts to the teeny-tiny supermodel wearing a bra for the first time in her life: “It’s a miracle… I’ve just grown breasts!” she marvelled recently. But there has also been a comeback for statuesque 1990s models, with Claudia Schiffer, Naomi Campbell and Linda Evangelista dusted off to front new ad campaigns. Their low-fat bodies are largely unchanged since their heyday, but the wider hips and athletic tone are a far cry from the death-camp-teen look most of the noughties catwalk models have been rocking. Condé Nast, publisher of Vogue, has now gone one better. Its new fashion title, Love, featured a naked size-28 woman on the cover.

Of course, it’s easy to dismiss fashion as a duff social barometer, with nothing to say about life as it’s really lived. But around the same time that the rag trade started photographing women without eating disorders and knocking out size-20 clothes (Evans is one of many retailers poised to launch a new plus-size range), the Spam manufacturers upped production to 150,000 tins of bargain luncheon meat a day. Meanwhile, McDonald’s has seen a double-digit percentage rise in yearly UK profits, and Marks & Spencer has been selling out of Lancashire hot pots and sticky toffee puddings.

Lean times make for fatter tums. Food-wise, it’s simple economics. Pre-packaged, preservative-laden meals and junk food are cheap. There’s also the comfort factor. Retail analysts say that in a recession we forgo luxuries such as foreign holidays and handbags but replace them with smaller treats such as chocolate and DVDs. Gym memberships take a hit and we spend our downtime thriftily slobbing on our sofas. But is there something deeper going on in our brains? Five years ago, Terry F Pettijohn and Brian J Jungeberg of Mercyhurst College, Pennsylvania, published an exhaustive study of the bodily dimensions of Playboy models from 1960 to 2000. They wanted to see if a tough economy had any correlation to the physical preferences of pornographers. Intriguingly, the pair discovered that “when social and economic conditions were difficult, older, heavier, taller Playboy Playmates of the Year with larger waists, smaller eyes, larger waist-to-hip ratios, smaller bust-to-waist ratios, and smaller body mass index values were selected”.

Apparently, in times of crisis, men prefer their women with a touch of Valkyrie. Dr Leif Nelson, of New York University’s Stern business school, has corroborated this. His study revealed that men who are financially insecure are more drawn to heavier women than men who are confident about their bank balances. (He also found that men like fat women more before a meal than after it — perhaps they want to eat them?) The biology isn’t hard to decode: they don’t want to be lumbered with some waify dependent when they are struggling for their own survival: they want to be well covered.

And neither study took society’s decade-long obsession with “thinness” into account; that wearying daily analysis of jutting celebrity pelvises and matchstick arms. Crazy as it seems, only a few months ago, Madonna’s sinewy calves or Victoria Beckham’s angular collarbones seemed like bona-fide dinner-party conversation-starters. Now that we have some actual problems, debating some neurotic x-ray’s eating habits seems pointless, to say nothing of panicking about our own bodies. Clearly we had too little to worry about if “Is it gluten-free?” or “Should I eat carbs after 6pm?” were troubling questions. Who cares? Malnourished women aren’t interesting any more. They’re depressing. And the six-pack, once evidence of having luxurious amounts of time and money to devote to self-sculpture, now looks like a feeble attempt at control in an uncertain world. Even worse, it implies a desperately high level of self-involvement. Fat people, meanwhile, look better every day. Why? Because they look carefree. So heave a sigh of relief and let your gut out. Kate Moss might be “fat”, but it turns out she’s bang on trend, as ever.

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