A third of children with eating disorders seen by the Cambridgeshire And Peterborough NHS Foundation Trust are waiting too long to begin their treatment, with some having to wait months for care.

Leading mental health charities have warned that a “postcode lottery” is leaving many youngsters struggling to access the care they need, with “patchy” services leading to “significant local and regional variation” in waiting times.

NHS guidance says that patients should begin treatment within four weeks of referral, or within one week for urgent cases.

The latest figures from NHS England however show only 67% of children and under 19s referred to the Cambridgeshire and Peterborough NHS Foundation Trust began their treatment within those windows in the 12 months to June, putting its performance well below the national average.

Some patients were left waiting months for help, with seven youngsters waiting 12 or more weeks.

Overall, referrals are on the up in England, increasing from 5,725 between July 2016 and June 2017 to 7,054 the following year.

In the case of the Cambridgeshire and Peterborough NHS Foundation Trust, cases rose from 35 to 151 over the same period.

Across England, 81% of patients began their treatment within the target window over the same 12 month period, and in some parts of the country the number reached almost 100%.

More than a quarter of providers that returned data for the past two years performed worse against their targets this year than they did the previous year.

This is despite government efforts to drive down waiting times, with NHS trusts and other healthcare providers given a deadline of 2020 to ensure they are meeting their targets in at least 95% of cases.

Mental health charity YoungMinds says this “ambitious” target is “unlikely to be achieved”.

Tom Quinn, director of external affairs at eating disorder charity Beat, agreed, adding: “At the moment it is difficult to be confident that the target will be met, given that so many trusts appear to be falling behind.

“The extra money the Government put forward hasn’t been ring-fenced and our analysis shows that not all Clinical Commissioning Groups are spending it on eating disorder services.

“We are concerned there is so much variation - early treatment is crucial, and some trusts are playing catchup.

“We would urge all CCGs to look at the findings and to ensure that there is proper investment in their area.”

The national rise in eating disorder cases has been reflected in the number of people calling Beat’s helpline, with “more and more people” seeking treatment.

“It’s hard to tell if that means more people are suffering from eating disorders, or if there is increased awareness of them and better awareness that treatment is available,” Mr Quinn said.” It does put increased strain on services though, so we need to make sure there is enough money for them to keep up.”

Marc Bush, Director of Policy at YoungMinds, said: “It is encouraging to see an increase in the number of young people receiving treatment across the UK.

“Given an anticipated increase in the amount of young people needing treatment for eating disorders, it is vital that the Government commits to a new funding settlement for children’s mental health services which will ensure that it can properly meet the scale of the need.”

An NHS England spokesperson said: “More young people are getting the treatment they need for eating disorders, and there has been a significant improvement in treatment times for NHS care.

“An extra £30 million is going into children’s eating disorder services every year, with 70 new and improved treatment centres set up in 2017, covering the whole of the country, to ensure more young people get the right care, at the time, closer to home.”