A 12-year-old boy has become the youngest person in Britain to have a gastric band fitted, as doctors struggle to fight the child obesity epidemic.

The schoolboy is one of an increasing number of youngsters who have had the controversial weight-loss operations, despite recommendations that such high-risk surgery should be a last resort when other efforts to slim down have failed.

Figures seen by The Mail on Sunday show that 62 young people aged 18 or under had the stomach-shrinking surgery at NHS and private hospitals over a three-year period. They include the 12-year-old, one boy aged 13 and two boys aged 15.

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Indulgent: Natalie admits she gives daughter Talulah, aged four, sweets 'for an easy life'

Leading doctors and dentists blame parents for letting their children become so unhealthy that they need surgery – not just gastric bands but also operations to remove rotten teeth caused by sugary diets.

Professor Monty Duggal, head of paediatric dentistry at Leeds Dental Institute, who regularly operates on obese children to remove decayed teeth, said it was ‘a matter of national shame that we have these health problems when we are a wealthy, developed nation. The treatments I carry out all cost taxpayers money.

‘[Yet] as a professional in my field I have to approach parents with great caution. I can’t accuse parents of anything. But of course the parent is responsible for the child’s welfare and health.’

He added that social workers would be quick to step in at any sign of a parent abusing a child, ‘yet you can have a child with up to 20 decayed teeth in their mouth, a big fat face, seriously ill and having to be admitted to hospital for a serious operation under general anaesthetic without consequence for the parent.’

Denisa, 13, visits King’s College Hospital in London with her parents to be assessed for the £12,000 surgery

'One last treat': Denisa and her family in McDonald's - minutes after she was assessed for surgery

His comments come as a new Channel 4 documentary series reveals some of the extreme cases doctors have to deal with at specialist NHS clinics that offer gastric bands to under 18s.

The two-part series called Junk Food Kids: Who’s To Blame? features one 13-year-old schoolgirl who weighs 16st. Denisa, who came to Britain from Romania four years ago, visits King’s College Hospital in London with her parents to be assessed for the £12,000 surgery.

During a consultation about the operation, Denisa’s mother, who is not named in the programme, is questioned about the efforts her daughter has made to lose weight.

It's a matter of national shame that we have these health problems when we are a wealthy, developed nation

Speaking in broken English, she explains: ‘We keep on diet, all three together. It was very good, but now we cannot keep. She cannot give up bread – she likes very much.’

The family are given a detailed diet plan when they leave in a final attempt to try reduce Denisa’s weight without surgery. But just 15 minutes later, the family are shown heading straight to a nearby McDonald’s for ‘one last treat’.

The documentary series also features children attending NHS obesity services in Leeds and being treated for associated conditions such as dental decay.

One of these youngsters is four-year-old Talulah, who due to her weight struggles to fit into a uniform designed for nine-year-olds for her first day at school. In a shameful admission, her mother, referred to only by her first name Natalie, says despite her daughter’s obesity problems she continues to indulge her with sweets for an ‘easy life’.

‘I like to just have an easy life,’ the 29-year-old says.

‘I think everyone just wants an easy life. Sometimes I think to myself no I shouldn’t give in – but I do.’

In another heartbreaking scene, Talulah is seen in tears after surgery to remove eight of her teeth, which have badly decayed because of her sugary diet. But Natalie seems equally unapologetic about the situation. She said: ‘I know that’s my fault, but it was easier for me on a night to give her a bottle of juice than to try to sit up with her all night and get her back to sleep.’

In the same documentary, consultant Fiona Campbell, who works at Leeds Children’s Hospital said: ‘I think the parents have to be blamed for overweight children, but they have to be helped.

Critic: Professor Monty Duggal blames parents

‘Although this is difficult for them – and we can understand chastising children and stopping them doing what they want is difficult – I’m afraid that’s their responsibility. It comes with being a parent.’

Denisa’s family also continues to make a string of excuses about their daughter’s failure to reduce her dangerously high weight and why they are putting her forward for the surgery.

Her father Virgil says: ‘Dieting, changing your eating style, is about the power of willing.

‘And we’ve demonstrated we’re not that strong.

‘She tried to lose weight when she was 11 and 12, but got fatter and fatter. But with surgery you don’t have to give up on temptations.’

Denisa herself admits: ‘My parents find it hard to keep to a diet. That’s why I can’t keep to a diet because they find it hard.’

Gastric band surgery is only offered to obese patients as a last resort, and children or teenagers must meet a strict criteria before they are even considered for the procedure. To qualify they must have a body mass index of more than 40, have reached puberty, have first tried to slim through dieting or exercise, and have a full understanding of the psychological implications.

Some parents, when they come to us, have the idea that if their child has the surgery it will act like a magic wand

But even with these stringent rules, Government figures show the number of young people under 19 having gastric bands on the NHS doubled between 2007 and 2013, when more than 200 children had the surgery.

The average cost of the operation is more than £7,000.

Official statistics from the National Bariatric Surgery Register, which is compiled from surgeons’ reports, reveal that the 12-year-old boy is the youngest child to have been fitted with a gastric band within this group, although it is not recorded if the operation was publicly or privately funded.

NHS statisticians said the youngest patient they had on record for bariatric surgery paid for by the Health Service was 13.

However, many surgeons argue that the stomach bands could save the NHS money through reducing levels of obesity and associated illnesses such as type 2 diabetes, which are estimated to cost the Health Service £5 billion a year.

Dr Lucy Stirling, a clinical psychologist at King’s College Hospital, said parents whose children are facing gastric band surgery can fail to take responsibility for their child’s weight issues.

She said: ‘Parents can be in denial of the part they have played.

‘But children need to be brought up to eat in such a way that they’re nurturing their body rather than slowly damaging it.’

Paediatric consultant Ashish Desai added: ‘Some parents, when they come to us, have the idea that if their child has the surgery it will act like a magic wand.’