One in ten people over 40 now has diabetes, amid a doubling in the numbers suffering the condition within two decades, new figures show.

The research by Diabetes UK suggests that by 2030, around 5.5 million people will be suffering from the condition, which is fuelled by obesity.

The figures show major variation in levels of the condition across the country, with Bradford the “diabetes capital” with rates three times those of Richmond, in south west London.

In total, there are 3.8 million people diagnosed with diabetes in the UK – an increase of 1.9 million since 1998, the figures show.

Nine in 10 cases are Type 2 diabetes, which is driven by obesity.

Almost one million more people are undiagnosed, the charity estimates, bringing the total number up to 4.7 million, a figure which is set to reach 5.5 million by 2030.