HEALTH bosses estimate there are about 4,000 morbidly obese people in Plymouth.
The figure applies to people with a body mass index above 40 who are at high risk of suffering weight-related problems such as diabetes and heart disease.
Local NHS chiefs have launched a wide-ranging review of the city's strategy aimed at tackling rising obesity rates.
Only about 12 per cent of morbidly obese Plymothians are accessing the current weight management service, according to an NHS Plymouth report.
It states some city services are "fragmented and inequitable" and have excessive waiting times.
The review will look at how to significantly expand access, increase choice and focus more on early intervention.
The first stage has examined the 'Tier 3' weight management service for morbidly obese patients, based at Devonport's Cumberland Centre and the Mount Gould local care centre.
Deb Lapthorne, director of public health for Plymouth, said: "It is estimated about 4,000 people in Plymouth are likely to have a BMI over 40, if our population fits national averages.
"We have about 600 patients a year referred to the Tier 3 service from a GP. They are those motivated enough to make life changes.
"Four hundred of those choose to carry on with treatment.
"It's an excellent service, it's compliant with NICE (National Institute for Clinical Excellence) guidelines and the people using it are generally very pleased.
"That's great, but we are interested in what we can do for the 200 people who don't continue."
Set up in 2006, the 16-week Tier 3 programme concentrates on diet, exercise and psychology. Free for patients, it also helps people consider and prepare for the drastic surgical procedures of stomach stapling and gastric banding.
Emphasising the importance of a review, Ms Lapthorne said motivation is a key factor in people losing weight.
She said: "We want to make sure that whenever someone wakes up and thinks 'today's the day I'm going to lose some weight', there are a range of services in the city for them, some NHS and some others."
She said health bosses want to look at helping people at earlier stages, before they become obese through a range of services for children and adults.
Current help includes the weight management service, support from healthcare professional such as health visitors, school nurses, practice nurses, GPs, and from private slimming organisations.
There is also a children's specialist clinic and after-school MEND programme for children and their families.
Measures being considered including developing support services offered by GPs, providing health trainers to work in the community, and redeveloping the MEND after-school weight programmes for children.
The report states the whole service will need clear coordination, with input from education, the city council and health bodies.
Papers also mention that Derriford Hospital becoming a specialist centre for bariatric surgery – stomach stapling and gastric banding – has "significant implications" for the weight management service.
They state it is likely the service will be expected to provide patients with specialist pre- and post-surgery support.
According to government figures one in four Plymouth adults are obese, have a body mass index (BMI) of more than 30.
Anyone worried about either weight is affecting their health should contact their GP for advice.
For more information about the above services contact Sarah Hind on 01752 434623.
Tan Fry of the National Obesity Forum on the "fat map" of the UK which shows high levels of obesity in Plymouth.