Backstage at Topshop Unique during London Fashion Week last month, fashion’s sad cliché lives on. A waif-like child-woman – her skinny jeans all baggy of bottom – is scrutinising a Prêt salad from a trestle table groaning with untouched sandwiches. After turning it this way and that, she eventually rejects it and slinks off for a cigarette. Another model, Danijela, from Serbia, is sitting all alone. “I feel under huge pressure to keep my shape, so I eat just small portions,” she admits. (I later check her vital stats online: a very unfat 33-22-34.5 at 5ft 10in.) She continues: “I’m getting older. At the New York shows, all the girls were 14 or 15.” And she is? Just 20. “I do think a lot about having to do something else. All the clients want skinny, young girls. They say they want healthy, but really they just want skinny.” You can never be too thin or too young in fashion, it seems.

Moving on from size zero, the big look right now is the “sacrificial virgin”: the trembling ingénue straight out of school, all gangly and underdeveloped. Why? Because everyone is clamouring for the credit of discovering the latest new face. “You want to make your stamp with someone fresh, not with a model who has done a million other jobs,” says a stylist who prefers to remain anonymous – let’s call him John. He works for several international glossy magazines, including this one. Designers have more commercial motives for hiring these “virgin” girls: beyond that old belief that clothes hang better on thin people, the concept they want to capitalise on is innocence.

“The thinking goes that women want to buy into the fantasy of being impossibly young and impossibly skinny,” says a casting director, who also asked not to be named. (Most people I spoke to for this piece asked for anonymity. Few in the industry are willing to speak their minds publicly – there’s too much money at stake.) “You’re not going to buy an outfit because you saw a saggy-breasted woman wearing it,” she continues. “After all, look what happened to Isabella Rossellini’s modelling career.”

“What summed up the situation for me was when I got a phone call from a booker asking me what I was doing for half-term,” says an (again, anonymous) eminent fashion photographer. “I presumed he meant what I’d be doing with my kids. Then it dawned on me: he had a load of schoolgirls for me to see.”

With their blonde hair, pale skin and eastern European features, some are even calling the trend Aryan (not forgetting Naomi Campbell’s recent rant that the industry is more racist than ever). “This is no-name beauty,” says Claudia Croft, Style’s fashion features director. “They’re so young, you can’t really communicate with them, and nobody can be bothered to find out their name because they’re over after one season.” Thanks to the dubious cachet of modelling, there’s an infinite supply of fresh blood, so there’s no need to look after the girls they’ve got.

“Fashion is at a crisis point,” says Professor Susie Orbach, psychoanalyst and co-founder of Any-Body.org, a campaign for the acceptance of body diversity. “It has to get its house in order: it was put on notice last year, but it really hasn’t responded.” Specifically, Orbach called for a ban on under-16s modelling at London Fashion Week, or those who have a body mass index (BMI) of less than 18. “Did we have anorexia in these numbers 25 years ago?” asks Orbach. “We are hard-wired to want to join in with whatever is beautiful. The industry is fantastically creative – there’s no reason why they can’t retrain our eyes to a whole variety of images.”

Things are happening, however. The latest issue of Pop magazine is devoted to Stephanie Seymour, the original Victoria’s Secret model and now a 39-year-old mother of four – and there’s not a single bony corner to her. “In fashion, you want to do the opposite of what’s gone before,” says Katie Grand, Pop’s editor-in-chief and superstylist. “From having seen 25 sample-size Sienna Miller covers, it seemed obvious to me to use an iconic, curvier, older woman in not much clothing.”

Tellingly, Seymour was shocked by the attention. “She was almost confused by her status as a goddess,” says Grand.

Meanwhile, Prada’s spring/ summer catwalk was dominated by the ample, unfettered bosom of Lara Stone, and curvaceous models (relatively speaking, of course) Isabeli Fontana and Guinevere Van Seenus are getting big campaigns (Chanel, Versace and Valentino) and posing for the Pirelli calendar and Victoria’s Secret. What is being channelled here, through the use of real women, is sexiness. “Sixteen-year-olds don’t even know what sexy is,” says a photographer’s agent, who is married to one of the world’s most famous photographers – let’s call her Sarah.

“The sex bomb is definitely of the moment,” says Grand. “But then, after working on the Stephanie issue, all I wanted to see was tiny, young girls when I styled the Proenza Schouler show. You go full circle so quickly in fashion.” Right back to square one, then.

Predictably, it’s a self-perpetuating trend: there are few curvy models, because the designers don’t make clothes that fit them. It’s why Behati Prinsloo, the white model from Namibia who measures in at 32-24-35, ended up being called a fat pig by a stylist; why Lily Cole, at 34-25-35, is often considered too big; and why Lily Donaldson was rumoured to be in competition with another model as to who could eat the least. Girls quickly learn to believe that losing weight pays, and there is no end of stories about girls being told to lose weight by their agents. “One model was made to have a breast reduction,” says Olly Paton, a stylist’s assistant. “The agency must have taken her to a really dodgy place, because the scarring was so bad. But she said she preferred that to being turned away from jobs.”

It is a pitifully conformist industry.

“There are few people at the top of the pyramid who decide what’s credible,” says our stylist John. “So lesser designers use skinny young girls to gain their fashion credentials. Everyone is trying to make a buck, so people are reluctant to break the mould.”

Some are keen to pin the blame on fashion’s gay camp. “The fashion industry is 70% gay men, and their opinion far outweighs the 30% of women and straight men,” says another international stylist. “Projecting that little-boy fantasy is one that gay designers go back to more and more.” It’s the straight men who are pushing for a healthier vision of beauty, reckons our agent Sarah, especially once they reach fatherhood. “Younger men don’t think about what they’re doing. But when they get to a certain age, they think, ‘These girls could be my daughters.’ ” But others point out that there are also women at the top still perpetuating the virgin look – Alberta Ferretti’s show in Milan last month was rife with sacrificial virgins, as was the London show for Daniella Helayel’s label, Issa. Miuccia Prada, a mother and arguably fashion’s most influential woman, interestingly has used the much fuller figured Prinsloo, Van Seenus and Stone in her recent shows. Unfortunately, it doesn’t seem to be rubbing off.

But not only is it damaging the girls, and those in society who deem them role models, it’s apparently not great for the industry. “There’s not much life left in fashion photography,” says one snapper, who photographs for Vogue, The New York Times and Style. “For a model to give to a photographer, she has to have lived and loved. If it continues down this route, we’ll soon just be shooting mannequins.” The photographer Nick Knight, who has always championed a wider parameter of beauty, agrees: “Things get boring when you only offer one vision.”

And it’s not serving the clothes: what might work for younger brands, such as Miu Miu, doesn’t work for all. “It’s hard to sell a sexy or sophisticated brand such as Halston or Donna Karan using skinny virgins,” says Croft. “It’s children trying to work women’s clothes. It just doesn’t match the brands – you need a bit of a hip for the clothes to hang properly. The fantasy is wearing a bit thin.” Literally.

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