Yesterday, a report by some of the country's leading doctors called for urgent action to tackle the consequences of the UK's obesity timebomb.

Health Correspondent Barry Nelson looks at how 'fat camp' has helped one teenager bring his weight down.

COLIN ruefully admits that he got stuck into the Christmas mince pies and turkey over the holidays. But generally speaking, the teenager is sticking to a formula which has seen his weight drop from a debilitating 33 stones down to a more manageable 25 stones in the last two years.

"To be honest, I didn't 100 per cent stick to the rules over Christmas, but things have been going really well recently. In the last fortnight I have lost another four pounds," says the 18-year-old, from Seaham in County Durham, who radiates a sunny optimism.

That formula - regular workouts at the gym, swimming, walking short distances rather than getting the bus and eating regular meals rather than snacking - was drummed into Colin at the so-called "fat camp" which has been run by Leeds Metropolitan University for the last four summers.

Now, if you ask Colin how he has managed to lose so much weight, he will reel off the philosophy of the Leeds summer camp, almost chapter and verse.

After yesterday's warning by eminent British doctors that something has to be done to tackle rising obesity levels, it is a message that more people need to heed.

The report - Storing Up Problems: The medical case for a slimmer nation - highlights the importance of targeting youngsters, after figures which showed dramatic increases in childhood obesity. Indeed the situation is so grave that experts are predicting that if current trends continue at least a third of adults will be obese by 2020. Today the figure stands at one in five.

Specialists agree that obesity puts an extra strain on the heart, circulation system and skeleton and can lead to an early death.

The basic problem is that Brits take too little exercise, spend too much time sitting down and eat too much unhealthy food. And in an era when most people do physically undemanding jobs and travel to work by car it is hardly surprising that the problem seems to get worse with each generation.

Despite the doctors' call for action and Government efforts to encourage exercise and healthy eating in our schools, things look as if they will get worse before they get better.

Colin makes no apologies for his admiration for the summer fat camp - it has utterly changed his outlook on life as well as his appearance. But what the teenager can't understand is why the whole country is not covered with similar camps, helping youngsters like him cope with obesity.

"Going to the camp has made a huge difference to me. My confidence has been boosted, I can go into a high street shop and buy a t-shirt or jacket instead of having to go through a mail order company. For me, camp has turned my life around," says Colin, who is now studying four A-levels at the City of Sunderland College in Shiney Row.

Dr Paul Gately, the sports, exercise and health lecturer who has run the annual summer camps since 1999, is delighted at Colin's process but deeply frustrated that he is unable to help more people like him.

"Colin has done brilliantly. He is still working hard, still battling with his weight every day but he is winning the fight," says Dr Gately.

The basic problem is funding. Despite published results which show that around 70 per cent of camp "graduates" are able to manage their weight more effectively, very few students have their fees paid by the NHS.

IN Colin's case, his local GP managed to persuade health officials to fund a three week placement for two years running. But last summer the NHS withdrew funding and the camp was forced to offer Colin a "training" place free of charge to ensure that the good work carried on.

Dr Gately was unimpressed. "Colin came on a three week placement and then after two years they withdrew funding, despite how successful it had been. We couldn't let him go back to the way he was before so we offered him a job last year and he has done a great job."

Despite four years of success, only around 12 per cent of campers are funded by the NHS. The rest have to rely on their parents to find up to £2,200 for the full six week residential course. "For every youngster who gets a place there are another ten whose parents can't afford it," says Dr Gately.

The Leeds-based academic would not only like to expand the number of places at his summer camp but see the concept rolled out to other parts of Britain. "We have been working on setting up community-based projects around the country, including the North-East. It is funding that is the problem," he adds.

Despite the problems, the camp will open this Easter for two weeks for the first time.

Dr Gately accepts that Government resources need to be put into preventative measures, such as school exercise schemes and increasing the amount of fruit eaten by children, but argues that more effective action needs to be taken to help young people who are already dangerously overweight.

"It seems that the NHS is playing a game and so are the politicians. They are all talking about what a problem obesity is but it seems to be a lot of talk and very little action," says Dr Gately.

"We are at the sharp end, dealing with families and getting thousands of calls each year. I would say you have got to offer something to kids who are already obese. You have got to treat obesity aggressively."

COLIN, who went back as a coach last summer and will do the same as a member of staff this year, agrees that preventative action should be taken in schools but believes that the summer camp environment is an ideal place to get healthy messages through to children.

"We need the same kind of education programme about food and nutrition in schools that we have at camp," he says. "You can take sweets away from kids and give them an apple but they won't want that apple if they don't know what the difference is between them. To them the only difference is taste. We need to explain why they should eat the apple."

Colin would also like to see a more inclusive approach to PE lessons.

"PE tends to concentrate on the more able kids - if you are overweight it means you are not included. There has got to be a more balanced approach so everyone can join in," he says.

While Dr Gately is hoping for a change in attitude towards funding, he says the basic principles of the summer camp can be applied by everyone.

"We eat far too many calories if we snack between meals. You should eat regular meals every day and take every opportunity to take exercise and burn up calories," he says. "The message is enjoy activity, enjoy eating and don't feel guilty."