Around two million people in England are at risk of developing type 2 diabetes – the highest on record.
NHS figures show there are 1,969,610 people registered with a GP who have non-diabetic hyperglycaemia, a condition which puts people at high risk of type 2 diabetes.
The NHS warned the scale of the problem is likely to be even greater because the growing obesity crisis is exposing millions more to the condition.
The health service has put in place measures to tackle the problem, such as the Diabetes Prevention Programme, which identifies people at high risk of diabetes and supports them in living a healthier lifestyle. The programme has had around half a million referrals.
Radical low calorie diets, which have been shown to stamp out recently diagnosed type 2 diabetes, will be rolled out by the NHS to 5,000 people from April.
Patients will be prescribed a liquid diet of just over 800 calories a day for three months, followed by a further nine months of support to help maintain their weight loss.
NHS chief executive Sir Simon Stevens said unless more people make a change, obesity-related illnesses will end up costing hundreds of thousands more lives and billions of pounds in higher treatment costs.
Professor Jonathan Valabhji, NHS national clinical director for obesity and diabetes, added it is wrong to think that the obesity and diabetes crisis is limited to those in middle and old age.
“There around 115,000 younger people suffering type 2 diabetes or at risk of developing the condition,” he said.
Around nine out of 10 people with diabetes have type 2 and there were over a million obesity diagnoses in hospital admissions last year.
Projections show that the growing number of people with diabetes could result in nearly 39,000 extra people suffering a heart attack in 2035 and over 50,000 experiencing a stroke.
One in six hospital beds is now occupied with someone with diabetes.
Chris Askew, chief executive at Diabetes UK, said more than half of all cases of type 2 diabetes could be prevented or delayed by supporting people to reduce their risk by losing weight where appropriate, eating healthy food and being more active.