`After each time I got sick, I felt every emotion - happiness, relief, calm, but then guilt, fear, depression. I'd feel guilty that I had eaten the food and then guilty that I had got sick again. I'd feel `This is not good' and wonder how, when, was I even able to stop doing it."

Michelle (19), is no longer bulimic. Slight, coy and disarmingly attractive with fine fair hair about her face, she smiles frequently as she recounts the background to an illness which afflicted her for four years. Though unsure why she started making herself sick, at the age of 14 in the Gaeltacht, she says "missing home" had something to do with it. There was also the usual pubescent concern with weight. She did gymnastics and so "had to be thin". She "hated" her thighs in particular, and besides, "when you think about it, everyone pretty is thin".

Asked whether fashion magazines were a factor in her illness, she thinks a moment.

"Well, it's just that the idea of thin is better is always there. I do hate all those magazines where the models are perfect. And mannequins. Oooh, if they were real women they wouldn't menstruate they're so thin."

As her illness developed Michelle didn't have to push her fingers to the lower recesses of her throat to force the oesophagus to give up the food it had just swallowed.

"I just had to lean over and the food would come up. I'd lie about what I had eaten, or give my food to the dog. Obviously at the start you'd feel hungry but your hunger goes, and when I did eat I'd think `That's a pound of food. That's a pound of weight that will go on me'. And I'd want to get rid of it.

"I found it began to control what I did in my social life. I'd feel uneasy going out because I'd be afraid there might be food there. I spent a lot of time in my room by myself."

It was "never terrible". She never got "really depressed", but she came to rely on the bulimia.

"If someone annoyed me, rather than talk about it I'd go to the bathroom. Vomiting gave great immediate release." And just as quickly, she says she knew, in the long term, she felt trapped by it.

This conflict that an eating disorder engenders in the sufferer is summed up by Ms Jennifer Kelly, chairwoman of the eating disorders support group, Bodywhys.

"An eating disorder is the sufferer's friend and foe. One woman I met put it very well when she described the difficulty of letting go of an eating disorder: `Emotional safety is more important than physical health'. "

Though most begin as a simple diet, the diet begins to serve wider functions for the individual. Small food restriction develops into skipping meals, in the case of the anorexic, or vomiting in the case of the bulimic. The behaviour soon spirals out of control, says Dr John Griffin, director of the eating disorders unit at St Patrick's Hospital in Dublin.

Weight loss, he says, gives a sense of achievement, power and control to an individual who may feel they have no control over the rest of their lives. Vomiting may provide a safe outlet for painful emotions which have often been channelled into guilt about food, and/or self-disgust, ostensibly about eating, but usually about a myriad of other things.

Though eating disorders are extremely complex illnesses, with numerous causes, Dr Griffin sees a direct correlation between their increase over the past 30 years and the rise of the dictum, "thin is beautiful".

About 14,400 people are thought to suffer from either anorexia or bulimia in this State.

"Where were all the anorexics and bulimics when Marilyn Monroe and Jane Russell were around?" he asks. "I have enormous sympathy for pre-pubescent girls looking at glossy magazines, television programmes and MTV."

It's certainly nobody's imagination that "slim" is more likely to make it in the media. According to research carried out by the British Medical Association this year, models and actresses in the media generally have 10 to 15 per cent body fat compared with the average healthy woman, who has 22 to 26 per cent body fat. "Slim is best" is the omni-present dictum, and though he does not see this as the reason behind every eating disorder, Dr Griffin is in no doubt that if things were different, fewer young women would turn to weight-loss and -control as a means of feeling better about themselves and achieving a sense of control over their lives.

"It has to be a factor," he says.

The Minister of State at the Department of Health, Ms Mary Hanafin, agrees but wonders how much can be done to address this factor when so much of the size- and fashion-agenda is set by powerful British and American media.

"I think we need to tackle this at the `demand' end - with the young girls themselves, to work on their self-esteem and assertiveness." She points to the social and personal programmes introduced to the school curriculum in recent years.

Dr Griffin would like to see more, such as a dedicated task force or other Government initiatives to heighten awareness of the issues. His suggestion of an Eating Disorders Awareness Week is something already held annually in Britain.

Ms Kelly would like a regulation of the Irish fashion and advertising industries, compelling them to represent a wide variety of shapes, sizes and colours with their models.

Michelle became a patient of Dr Griffin's - or Dr John as she calls him - four years ago. She has not vomited for a year.

"The bulimia is part of me and I'm not ashamed of it, but it's in the past. I am afraid of it starting again, because there are always times you feel down. But I talk now about what I'm feeling. Getting better was hard work, but it's so worth it. I'm happy now, and you can't be happy when you're trapped by food."