Hospital admissions for eating disorders, which carry the highest death rate of any psychiatric condition, have leapt 16 per cent in the last year and are up by almost 50 per cent in a decade.
Experts blamed the rise on a failure by doctors to diagnose those affected early in the course of their illness, before it takes hold. There has been no increase in eating disorders overall for 20 years.
The Health and Social Care Information Centre (HSCIC) said there were 2,290 admissions of adults and children with eating disorders, including anorexia, bulimia and related conditions in the year leading to June 2012.
That is a 48 per cent increase on the 1,533 admissions a decade ago in 2002-3. More than nine out of ten patients were female and over half were young people aged from 10 to 19. The ages ranged from under 5 to over 60.
The small number of very young children hospitalised (under age 10) are thought to have had mechanical problems with eating, distinct from the psychiatric condition, a spokesperson for the HSCIC said.
The eating disorders anorexia and bulimia are associated with low self esteem and a desire for control which becomes linked with body shape, size and weight. They carry a high risk of death by suicide or starvation, rising to 20 per cent after 20 years.
The US singer Karen Carpenter, Scottish child star and TV host Lena Zavaroni and Brazilian model Ana Carolina Reston are among celebrities who have died from anorexia.
The eating disorders charity b-eat said a media and social culture which focused on women's weight and shape aggravated the condition though it did not cause it. An estimated 1.6 million people suffer from eating disorders.
Susan Ringwood, chief executive of B-eat, said: "I spoke to a 12 year old girl who said: ' Why have I got to go to hospital when they [celebrities] are on the front of the magazine.' It reinforces their view that they are not ill - trapping them in their illness."
She added: "We know that 40 per cent of callers to our helpline have not spoken to a health professional. Lots are not putting themselves forward. Studies show community treatment has better outcomes but it is very variable across the country. People are not getting early treatment. Hospital admission is a last resort."
The longer the condition went "unchallenged" the more serious the consequences, she said, including osteoporosis (thinning of the bones) caused by poor diet.
"We see girls of 20 with the skeleton of 80 year olds," she said.
Dr Lucy Serpell, a clinical psychologist at University College London and expert in eating disorders, said: "The problem is the lack of good out-patient treatment and the failure of GPs to pick up the disorder and refer. When the patients come to us they are so unwell we have to get them to hospital to be stabilised. We don't like admitting 15 year olds to hospital."
An outpatient service for eating disorders established three years ago in north east London had seen admissions fall in three of the four boroughs where it was available - but not in the remaining one.
"We can see the difference - patients get admitted to hospital more in the fourth borough because they are not being treated soon enough. All the evidence shows people are better off where there is a specialist service."
In anorexia sufferers lose weight rapidly, becoming skeletal and ill. Bulimia typically starts with an effort to restrict the diet severely, but this cannot be sustained and ends with a binge, followed by vomiting and the cycle begins again. Eating is the one area of their lives that they feel they can control.
"I think it is mainly the pressure to look a certain way in the media"
Charlie Crompton, 21, spent six months in hospital when she was 17 after an eating disorder led to her weight plummeting to five stone.
“It started when I was 15 but it wasn’t until I was 17 that I was admitted to hospital. At my worst I weighed five stone. My mum had been pressuring me to go to the doctors as I was just getting thinner and thinner, they kept weighing me and I kept losing weight so the next step was hospitalisation. I think my illness was due to lots of different reasons. Just growing up is hard sometimes. I was also under a lot of exam pressure and I felt under pressure from my friends and the media to look a certain way. I wanted to look good.
Looking back it now all seems very strange. I think that when you’re ill your brain isn’t working properly so you can’t really understand what’s happening or why you are acting the way you are acting. I didn’t realise I was ill. In hospital they put you on a feeding routine to get you back into eating. That restores your weight and as your weight comes back up your brain starts to work normally again. When you have gained enough weight they let you out of hospital and you start therapy to stop you doing it again.
“For me I had actually booked a holiday about a year before so I needed to get out of hospital to go to America. I don’t think they were convinced I was ready but I was really determined not to miss that trip. I was discharged on the Friday and went on holiday on the Monday on condition that I had lots of checkups and support as soon as I got back.
“I’ve now been recovered for almost four years. I can understand why the figures might show a big increase in teenage girls being admitted to hospital. I think it is mainly the pressure to look a certain way in the media. But there’s also a lot more awareness nowadays so perhaps it is also that more people are coming forward for help.”