Dozens of websites that show pictures of anorexics and offer advice on how to starve and what drugs help you lose weight have been closed by an internet service provider.
Yahoo! closed the sites this month because the numbers had increased dramatically.
But many other similar sites, run by peoplewho have anorexia nervosa, remain on the internet, to the alarm of New Zealand eating disorder services.
Nearly 400 websites worldwide contain hints on how to suppress appetite, what drugs help weight loss, and exercise routines.
Counsellors and internet experts the Herald spoke to said they did not know of any similar New Zealand-based sites, but they were a big concern.
Anna Hedley, coordinator at the Eating Disorder Service in Auckland, said secrecy went hand in hand with anorexia, which was why it was difficult to tell how influential the sites were.
"Quite a big part of an eating disorder is secrecy and shame ... There might be times when family would not know if people were accessing these sites or not."
Anorexia was like a psychiatric illness. Overseas figures showed it affected about 1 per cent of the population.
Many factors were involved in the complex disorder, including personality, family dynamics, social factors and history. This made it difficult to treat.
"Often people don't notice how serious the illness is," said Ms Hedley.
"We see how bad their health becomes, and seeing websites promoting it is very concerning."
The sites were particularly worrying in regard to young people, who might not be as discerning as adults. Some might be more inclined to develop the disorder.
But Ms Hedley said the internet could also be used in a positive way. Some eating disorder clinics were using it for online treatment.
The spokeswoman for Yahoo! Australia and New Zealand, Anna Featherstone, said it was hard to tell if any anorexia sites were operating out of New Zealand.
Anyone could set up a club on any topic through Yahoo! "We don't actually patrol the clubs." If a user alerted Yahoo! to a site that might be hurtful, it would be scrutinised. "Someone will look at it and make a decision."
