Into this minefield steps Jen Hunter, a 24-year-old mother of one who took part in a Channel 5 programme called Make Me a Supermodel. Hunter is a size 12 and gorgeous. The show used the tried and tested formula of featuring a viper-tongued panel of “experts” and then relying on a public vote to find a winner. The panel called her “too fat” and frequently reduced her to tears.

They championed another model, Marianne Berglund, 18, who was praised for having a “stunning” body despite being clinically underweight with a body mass index of 16.1, ie, visible ribs and protruding hipbones. But sanity eventually triumphed: the public voted Berglund off, and Hunter won the top female slot. Days before the final, a Brazilian model called Ana Carolina Reston died, aged 21, of kidney failure brought on by anorexia having eaten only apples and tomatoes. She was the second model to die in months from eating-related disorders.

So Hunter’s victory was both cheering and nice: it proved that a scrawny, deliberately stunted body is not necessarily the kind of look people fancy. Models can be jaw-droppingly beautiful, but that doesn’t automatically make them sexy. Like Sophie Dahl, Hunter is, very unusually for someone in her profession, genuinely sexy. Though her face is pretty, her sexiness mostly has to do with her big size 12 body. Bones, no matter how beautiful, aren’t sexy; the right amount of flesh is. Hunter said: “People need to realise that to be beautiful doesn’t mean you have to be the size of a 13-year-old boy.”

Her story encapsulates the critical state we’re in when it comes to body issues and self-image. Most adult women are on some kind of unnecessary permanent diet, while their young daughters are falling prey to anorexia and bulimia. We ignore the correlation between a weight-obsessed mother and a starving daughter at our peril. If the mothers are not on a permanent diet, they’re grossly overweight and producing grossly overweight children; and everyone is surrounded by images of emaciated women that make us feel incompetent and elephantine.

Why has this happened? The reason that’s churned out most often concerns the fashion industry and the alleged conspiracy between gay men and loony stylists to impose their distorted, misogynistic view of female beauty on the rest of us. Ergo, fashion people make you anorexic; ergo, Vogue makes you ill. That’s an incredibly simplistic take. But if fashion isn’t to blame, who is?

Well, we are. The fashion industry hasn’t changed; we have. It is a fact of life that models have always been a) thin and b) young. The difference is that, until recently, people understood that models were working women doing a job, that they made sacrifices, most obviously when it came to not eating very much, and were richly rewarded for it. Nobody in their right mind wanted to be these women: they admired them in the pages of a glossy magazine and admired the clothes they wore, and then forgot about them and got on with their lives. Models occupied the same rarefied stratosphere as movie stars. Women used to be able to separate real life from airbrushed fantasy. We can’t any more.

Our society has become so incredibly voyeuristic. Our appetite for celebrity trivia and paparazzi shots appears to be insatiable. Certain — mostly young, mostly stupid, mostly American — women have decided that it is necessary for them to look at all times like they’re in the middle of a photoshoot.

So they employ personal stylists to tell them how to dress; they employ PRs and managers; they employ trainers to give them a dream body; they employ a drug dealer; and they don’t eat much. Their raison d’être is to appear enviably glamorous, which as ambitions go is lame to the point of imbecility. Yet we don’t focus on the fact that mincing around flicking your extensions is not the be all and end all that these young women take it to be. So, where we should be hooting with derision, we come over all big-eyed and eager, and wonder how we, too, could look like an unusually emaciated, unusually orange sex worker wearing an unusually expensive and unusually vulgar frock. Even if we’re 45. Even if we’re 12.

It’s an extreme version of the plastic surgery delusion, whereby a miserably unhappy woman with an unpleasant life saves up for a nose job she doesn’t need and is astonished to find, three weeks down the line, that her nose may be smaller but her life still sucks. Anyone who reads a glossy magazine has the potential to get taken in by the same thing: if I had Chloé wedges, men would follow me around at parties; if I bought a new Marc Jacobs handbag, my sex life would improve. Vast numbers of adult women appear to buy this stuff, crazy when you consider that the people who write it don’t believe it.

The problem is getting worse because the demarcations between ordinary life and the lives of a handful of celebrities have become completely eroded. Young people, with their peculiar sense of entitlement, are most at risk because they genuinely appear to believe that they don’t need to concentrate on academic work, since they’re bound to be plucked from obscurity — by a reality TV show or the like — and have a fabulous life handed to them on a plate. So they prepare themselves for the great day by dieting. (It can’t be an accident that research published last week proves that girls who move from the country to the city are five times more likely to become bulimic.)

Blaming the fashion industry for what is a societal problem is demonstrably not working. We need to look a little more closely at ourselves and ask how we’ve become so insecure as to believe in starvation as an indicator of beauty, and how we seem to have entirely lost touch with the idea that people’s interiors are more important than what’s on the outside.

I believe in diets — obviously, given my own trajectory — for people who need them. But I also believe in every woman’s right to be a healthy size 12, or 14, or 16, with pride. If Kate Moss, a midget in modelling terms at 5ft 7in, can change an entire industry’s perceptions, there ought to be no reason at all why a size 12 girl couldn’t do the same. Here’s hoping.

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