Nearly 7,000 children and young adults in England and Wales now have Type 2 diabetes as the rise in obesity continues, a leading charity has warned.
Diabetes UK warned the government must take action and has called for a ban on junk food advertising and restrictions on supermarket promotions of unhealthy foods.
The group said 6,836 people under 25 have Type 2 diabetes, according to data from GP surgeries in England and Wales.
"Type 2 diabetes can be devastating for children and young people. To help shape a future where fewer children develop the condition, we need continued commitment across society to create an environment that reduces obesity," said Bridget Turner, a director at Diabetes UK.
"We need to encourage healthy living by providing clear and easy to understand nutritional information about the products we are all buying, and protect children from adverts for foods that are high in fat, salt and sugar."
The charity linked the figures to obesity and said that unlike Type 1 diabetes, the chances of developing Type 2 is increased by being overweight and obese. Family history and ethnic background are also risk factors, the charity adds.
Type 1 diabetes is an autoimmune disease, which is unpreventable and not linked to being overweight.
Those with Type 2 cannot produce enough insulin and the condition causes the level of sugar in the blood to become too high, the charity said.
Diabetes UK warned the condition is more aggressive in children and young people than in adults and that more than a third of children in England are overweight or obese.
Professor Russell Viner, the president of the Royal College of Pediatrics and Child Health, a body for doctors specialising in child health, urged the government to act out on proposals set out in Britain's childhood obesity plan.
"For many children, the development of Type 2 diabetes can be prevented with lifestyle changes but this isn’t easy — they need support," Viner said.
A Department of Health and Social Care spokeswoman said: "We are committed to halving child obesity by 2030 and will be launching consultations to restrict promotions in shops for sugary and fatty foods, as well as a 9pm watershed ban on advertising.
"The upcoming NHS long-term plan will have prevention at its core and build on our existing work to keep people healthy and well."