This week's columnist is Eva Bellwood, a 16-year-old pupil at the Girls' Grammar School, Bradford

I'm sure most people are familiar with the AOL television adverts asking people to discuss what they think of the internet. I've always been a keen supporter of the net', however recently I've had my eyes opened to the darker side of the world-wide web.

It began when I caught part of a radio programme which said: ...pro-anorexia websites, aimed at seven to 16-year-old girls, hail Victoria Beckham as an idol...' I don't think I even knew what anorexia was when I was seven.

It made me think: Why are there websites created to promote such a serious condition? Shouldn't we be discouraging this sort of behaviour, as eating disorders can seriously damage the growth and development of pre-adolescent and teenage girls.

It is no longer in the confines of their peer group that girls suffer the peer pressure we believe to be the root of many problems in adolescence. Now with the freedom of the internet young people are exposed to everything and girls are subjected to that same kind of peer pressure by their internet buddies', friends they make on the pro-anorexia websites.

There are hundreds of pro-ana' websites creating an underground community through which girls encourage each other to crash diet and purge to become thin. The sites promote anorexia as a lifestyle choice rather than a medical condition and could easily persuade impressionable young people that anorexia is the lifestyle for them.

The attraction of these websites is that they make the girls feel like they belong to a community, whereas in the past eating disorders have been a lonely problem. The sites provide support the girls are unlikely to get elsewhere. By idolising skinny celebs the sites encourage girls to fast, under the impression that they will soon have the figure of whichever stick-thin celebrity they admire. And to keep the girls on the right path pictures of obese women are posted, with the message that this is what will happen if the girls give up on their diet.

So is it any wonder that the number of adolescent girls with eating disorders has doubled since the 1960s and that today 81 per cent of ten-year-olds are afraid of being fat. In a world where we are obsessed with body image and losing weight, young people go looking for ways to become thin, and pro-ana' sites convince impressionable adolescents that eating disorders are an easy, acceptable way to lose weight with the support of an online community.

The fact is that girls who suffer from anorexia may just be looking for some sort of support. If the only place they can get it is from pro-anorexia sites then that tells me not enough is being done to help people who suffer from the disorder. Sites providing advice about recovery and how to promote it would hopefully counteract the effects of the pro-ana' sites.

More needs to be done to limit the exposure that young people have through the internet. I think it is up to parents to make sure that their children don't roam the world-wide web too freely because it is their responsibility to protect them from the harmful effects of pro-ana' and other websites. The internet could become dangerous if nothing is done to curb the growth in the number of websites promoting self-harm.

Surely there is something wrong with a world where over half the population of nine and ten-year-olds have tried dieting and the number one wish of 11-to-17-year-olds is to be thinner.