The editor of Vogue has accused some of the world’s leading catwalk designers of pushing ever thinner models into fashion magazines despite widespread public concern over “size-zero” models and rising teenage anorexia.

Alexandra Shulman, one of the most important figures in the multi-billion-pound fashion industry, has taken on all the largest fashion houses in a strongly worded letter sent to scores of designers in Europe and America. In a letter not intended for publication but seen by The Times, Shulman accuses designers of making magazines hire models with “jutting bones and no breasts or hips” by supplying them with “minuscule” garments for their photoshoots. Vogue is now frequently “retouching” photographs to make models look larger, she said.

Her intervention was hailed last night as a turning point in the debate over model size that has raged after the deaths of three models from complications relating to malnutrition, and the decision of leading fashion shows to ban size-zero models.

Baroness Kingsmill, who headed the 2007 Model Health Inquiry on behalf of the British Fashion Council, said the stand taken by Shulman was “an encouraging sign” from one of the industry’s “leading lights.”

Beat, Britain’s leading eating disorder charity, says that 1.1 million people are affected by anorexia or bulimia.

Shulman claims that the clothes created by designers for catwalk shows and subsequently sent to magazines for use in their photoshoots have become “substantially smaller”.

The garments are typically sent to magazines six months before they appear in the shops and editors have no choice but to hire models that fit the clothes or fail to cover the latest collections from the leading designers.

“We have now reached the point where many of the sample sizes don’t comfortably fit even the established star models,” Shulman writes, in a letter sent to Karl Lagerfeld, John Galliano and fellow designers at Prada, Versace, Yves Saint Laurent, Balen- ciaga and other top fashion houses.The supermodel Erin O’Connor described the stand by the editor of Britain’s most prominent fashion magazine as “a huge breakthrough”.

"The fact that Alexandra Shulman with her enormous influence has opened this conversation means that it will have a huge impact,” she said. “It has . . . made it compulsorily relevant that we address this now.”

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