Four months after the city led the world in the Size 0 debate by banning ultra-skinny models from its catwalks, health officials are shining the spotlight on the growing number of “pro-ana” websites that glorify starvation diets.

Their first strike is against The Great Ana Competition, a website that awards a diploma to the girl who eats the fewest calories in a two-week period. They have filed a suit against the competition, which uses a scoring system that doctors said “would cause malnutrition in normal women”.

The site awards a single point for those managing to eat less than 850 calories a day, progressively increasing the points for those who eat even less. Competitors who manage to consume less than 150 calories in a day are given nine points, A 24-hour fast will earn them the maximum ten points.

Participants are also given additional points for activities that stave-off hunger — drinking half-a-litre of water is worth one — and for exercise. Ten minutes of running is worth a point, while “taking your [diet] pills and vitamins” is worth two.

Officials have condemned the website as a “serious health risk for young people”, particularly those already suffering from an eating disorder. They said that girls with anorexia or bulimia could die if they followed the website’s advice.

The regional government has asked a judge to determine whether the owners are criminally liable for the content.

In Britain health experts are increasingly worried about the proliferation of websites that promote anorexia as a lifestyle choice rather than a potentially fatal disease. Campaigners have been urging the Government to issue a formal warning about the sites, saying that the internet is luring young women to their death.

Last week the Eating Disorders Association said that there were more than 500 pro-anorexia sites on the internet with names such as Salvation through Starvation and Feast or Famine and slogans such as “Hunger hurts but starvation works”. Steve Bloomfield, of the association, said that the sites were often set up by young people with “no idea of the potentially deadly consequences of developing anorexia nervosa”. He added that they could be persuading sufferers to refuse treatment.

“About one in five people who don’t get appropriate treatment die prematurely, so [these websites] are literally killing people,” Mr Bloomfield said.

The Spanish internet site princesasdeporcelana.es.kz was not functioning yesterday, perhaps because of the legal threats. A message from the administrator said that Spanish newspaper stories had caused a deluge of visitors voicing their opinions “for and against” the city’s action.

“However, I don’t think that publicising the web page in the national media can help those people they are trying to protect,” wrote the administrator, pictured as a cartoon girl. Despite warnings that those under 18 should not enter, cached versions of the page showed a cartoon-filled site apparently targeted at young girls.

Chat room entries showed a symbol of a grim-faced girl in front of a dinner plate with a red cross over the top.

The website, which claims to examine eating disorders “from a completely personal perspective”, warns users that the information it contains “should not be followed”.

Many of the British websites also exchange tips on how teenagers can starve themselves, including “take up smoking” and “if your stomach rumbles, hit it”.

They idolise “thinspirational” celebrities such as Victoria Beckham and often refer to “my friend Ana” instead of anorexia to avoid discovery by parents.

Two models suffering from anorexia died recently in Brazil and Uruguay. In both cases the fashion industry came under criticism for using excessively thin models on its catwalks.

After Madrid banned models with a Body Mass Index of less than 18, other fashion capitals have come under pressure to follow suit.

Last month the fashion industry in Italy signed a “manifesto” with the Government, vowing to take a harder line on skinny models. All models will now have to produce health certificates declaring that they do not suffer from an eating disorder. They must not have a BMI below 18.5.

Britain has shied away from action. Tessa Jowell, the Culture Secretary, applauded the decision by Madrid to ban ultra-thin models but did not threaten to legislate, saying that it was up to the fashion industry to act.

The British Fashion Council, which runs the London Fashion Week, has refused to follow Madrid and Milan. Instead, it plans to write to designers and model agencies urging them to consider “the size and health” of the models.

Teen that served as ambassador for the Eating Disorders Association still struggling with her weight

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