Alongside the catwalk shows, the gossip and the glamorous parties, Paris fashion week was dominated by a billboard this year. It wasn’t for a glossy designer brand or an upmarket beauty house: it was a black and white picture of an anorexic model crouching ashamedly on the floor.

For a country known for its obsession with skinny women (as the title of that bestseller goes: French Women Don’t Get Fat), the response has been surprising. Rather than greeting the campaign with a Gallic shrug, Valérie Boyer, the Marseilles deputy, is now trying to bring in an anti-anorexia law. It states that it will become a criminal offence to “encourage another person to seek excessive thinness . . . which could expose them to a risk of death or endanger their health”, and it has magazines, fashion shoots and skinny models in its sights. Offenders risk two years in prison or a £24,000 fine.

Of course, the French fashion industry has lambasted the proposed law. Didier Grumbach, the president of the French Couture Federation, is known to be against it. “Although we all agree anorexia is a serious illness, none of us agrees with this,” says one fashion journalist, who does not wish to be named. “A law is not the way to fight it.”

Inès de la Fressange, the former muse of Karl Lagerfeld and brand ambassador for Roger Vivier, finds the whole idea “grotesque”. “This is the first time we have had a law against an illness,” she says. “We’d be better off with a vaccine against the idiocy of this government. We know anorexia is often found among young women who have problems with their mothers and not as a result of a picture.”

Anorexia sufferers concur. One I spoke to said: “Anorexia is not about wanting to look like a model or about vanity — that’s the furthest thing from your mind. It’s about wanting to vanish and not wanting to grow up. For me, it was a desire not to grow into my mother, who I hated.”

It seems odd that France should be the first country to come up with a law to fight anorexia. Having lived in France for the past eight years, I can tell you this is a place where you are more likely to be sent to prison for being too fat than too thin. Even though they are a lot thinner than us (a friend in Paris says the main difference between a French and an Englishwoman is “about 10 kilos”), French women feel they’re never thin enough. As Brigitte Papin, beauty editor of Madame Figaro magazine, says: “All French women, without exception, will always say they have 2kg to lose.” They watch what they eat, every day — one once told me, slightly nostalgically, that she hadn’t so much as looked at a croissant for 13 years. I had two of my children here. In hospital, the post-birth meals were all low calorie: the French don’t tolerate fatness.

Yet few blame their sacred fashion industry for this pressure. In fact, few women call it pressure; they just don’t like having to squeeze into their jeans. Any pressure comes from themselves. And women with anorexia don’t blame pictures of thin models, either. Even Isabelle Caro, the anorexic featured in the campaign, says the disease is “a result of a difficult childhood”.

So how does Boyer think that outlawing images of overly thin women will reduce anorexia? “I think it will open up a discussion on the . . . erroneous presentation of the body that the fashion industry and the media show us,” she tells me. “We are shown images of 50-year-old women advertising wrinkle cream, but they have not one wrinkle. We see images of models all the time that make us frustrated with the way we look — the result is extreme thinness on the street.”

But who is going to decide whether a picture is promoting thinness or a pair of shoes? If cases are brought to court, it will be up to the judge to decide if something is guilty of inducing anorexia.

Perhaps as a pre-emptive strike, French Elle recently published pictures of women who are proud of their curves. “They look disgusting,” said a French friend. “They should be at home dieting, not displaying their blubber on the pages of Elle.”

It seems magazines are only part of the problem.

Helena Frith Powell is the author of Two Lipsticks and a Lover (Arrow £6.99)

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