An obese 12-year-old boy has become the youngest person in Britain to have a gastric band fitted.
In addition, a 13-year-old and two 15-year-old boys have also had the controversial procedure, according to the Mail on Sunday.
The children are part of an obesity epidemic which has seen 62 young people aged 18 or under having the stomach-shrinking surgery over the last three years.
The issue is highlighted in a Channel 4 documentary series which starts on Wednesday night (Feb 18) called Junk Food Kids: Who's To Blame?
It 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, the family are given a detailed diet plan to try to 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 the children is four-year-old Talulah, who struggles to fit into a uniform designed for nine-year-olds for her first day at school.
Her mother Natalie, 29, said despite her daughter's obesity problems she continues to indulge her with sweets for an 'easy life'.
The mum said: "I think everyone just wants an easy life. Sometimes I think to myself no I shouldn't give in – but I do."
In one 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 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."
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.
"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."
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.
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 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."
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