* Revealed: 1 in 100 young women suffer from anorexia or bulimia<br />* GPs told: examine all underweight girls for signs of eating disorders

The Government last night called on GPs to screen all underweight women for signs of anorexia and bulimia following an investigation by The Independent on Sunday into the growing problem of eating disorders.

In the first major survey of its kind, this newspaper can reveal that more than one in 100 young women is affected by clinical eating disorders and up to six women in every 10 have "psychological issues" with food as a result of low self-esteem.

Doctors and government experts also called for a ban on the growing number of websites that promote the deadly illnesses as a "lifestyle choice" and encourage them to starve themselves to achieve "perfection".

Rosie Winterton, the health minister, said: "It is crucial that people with anorexia and bulimia receive the treatment they need and medical professionals need to be vigilant for the symptoms."

The IoS can also reveal that doctors are facing a disturbing new type of "multi-impulsive" bulimia that affects a third of patients. It is thought to be linked to an obsession with body size and image.

Women with this form of the illness, unheard of 10 years ago, not only purge themselves of food, but also cut their bodies, overdose and abuse alcohol. Experts believe the current obsession with obesity is confusing young women about their relationship with food.

The extent of the problem has prompted calls for greater emphasis on treatment for all. Psychiatrists have condemned the massive variation in services for eating disorders and the lack of specialist teams available to provide therapy for sufferers. The lack of services are particularly acute in Scotland, Wales and north-west England.

Many vulnerable patients are having to travel for treatment, putting an added strain on them and their families. One London clinic said it was receiving referrals from Yorkshire.

Professor Hubert Lacey, director of the UK's largest eating disorder clinic at St George's Hospital in London, warned that long-term anorexics were being left lonely and isolated because of the treatment gap.