Waif-like young men are also starving themselves to get the work they crave, report Ian Griggs and Lauren Veevers

As they sashay along the catwalks for the beginning of London Fashion Week today, stick-thin models will be the centre of attention. Yet not all will be women: boys are now under pressure to achieve "size zero" figures, too.

As fashion experts yesterday added to the row over skinny models, male stars of the shows revealed they are coming under enormous pressure to slim down to dangerously low weights. They say designers no longer want a buffed, toned male body to show off their clothes. Instead, they want waifs who can rival women in slenderness and androgynous looks.

One model, Ron Saxen, has written a book about his ordeal. It details how the pressure to be slim led to a battle with anorexia which, he says, almost killed him as he desperately tried to keep himself in work.

"My routine would be to get up, have a cup of coffee, run five miles, have another cup of coffee, cycle 20 miles, have a break and then swim 20 lengths of the pool," said Mr Saxen. "I put a lot of pressure on my heart. I had come down to 205lb, but I needed to get down to around 175lb to be a model. So I did it, and at 6ft 1in I was mostly skin and bones. But I got a contract."

Dior is one of the fashion houses leading the demand for stick-thin young men. Chris Ulyatt, 19, modelled for Dior last year. At 6ft 2in, he weighs only 10 stone.

"I was approached in the street by the head of Dior Homme," said Mr Ulyatt. "He was on what's called a boy safari. All the lads on the catwalk were tall and skinny and androgynous-looking. It's what they go for."

Health experts are warning of more men developing eating disorders. Janet Treasure, director of the eating disorders unit and professor of psychiatry at Guy's, King's and St Thomas' medical school in London, said that images of male models had an effect on men that was comparable with the size-zero fad among women.

The London Development Agency, which sponsors London Fashion Week, is to look at the pressure put on models to be thin and will examine whether the promotion of size-zero models leads to eating disorders.

Additional reporting by Marie Woolf

'The Good Eater: the true story of one man's struggle with binge eating disorder' by Ron Saxen is published next month

The Slim Line

Increasingly, designers want wafer-thin male counterparts to the female size zero. The hot look is tall and gaunt. Health experts say this sends a bad message to men prone to eating disorders.

David Lindwall

Modelled for: Dior Homme, Moschino, Paul Smith

Height: 6ft 2in

Waist: 29in

Body Mass Index (BMI): around 19

Nicolas Bemberg

Modelled for: Gucci, Lanvin

Height: 6ft 2in

Waist: 32in

BMI: 19.3

Chris Ulyatt

Modelled for: Dior Homme's campaign last year, designed by Hedi Slimane

Height: 6ft 2in

Waist: 29in

BMI: 18