More than one in 10 adults in South Yorkshire have blood sugar levels which put them at risk of developing diabetes.
In Sheffield, 49,237 people – 10.6 per cent of adults – are judged to be in danger of developing type two diabetes, which is linked to obesity and an unhealthy lifestyle.
In Rotherham, 24,594 people – 11.7 per cent – are at risk, while in Doncaster, Derbyshire and Barnsley, the figure is 11.8 per cent.
The figures, from Public Health England, have emerged from the most rigorous study yet of a condition known as non-diabetic hyperglycaemia which can be a pointer towards type two diabetes.
The study has helped inform a new programme encouraging people to lose weight and take more exercise to reduce their risk of developing the condition.
Paul Twomey, medical director for NHS England in Yorkshire, said: “There are too many people on the cusp of developing type two diabetes and we can change that.
“The growing body of evidence makes us confident that our NHS Diabetes Prevention Programme will reduce the numbers of those at risk going on to develop the debilitating disease.”
Across most parts of the country, more than one in 10 adults are at risk of type two diabetes and, in some regions, the risk is around one in seven.
Some 2.9 million people in England are already diagnosed with type two diabetes, with obesity seen as a key driver.
A separate study found that encouraging weight loss and healthy living as part of a dedicated programme could prevent 26 per cent of people with high blood sugar levels from developing type two.
Figures suggest that type two diabetes already leads to 22,000 early deaths every year and costs the NHS around £8.8 billion.
Duncan Selbie, chief executive of PHE, said: “We know how to lower the risk of developing type two diabetes: lose weight, exercise and eat healthily, but it’s hard to do it alone.
“PHE’s evidence review shows that supporting people along the way will help them protect their health and that’s what our prevention programme will do.”
Barbara Young, chief executive of Diabetes UK, said: “Having high blood glucose levels significantly increases your risk of developing type two diabetes, which is a serious health condition which affects 2.9 million people in England, and can lead to devastating complications such as blindness.”