More than 12 million people in the UK are now living with either diabetes or prediabetes, according to new data from the charity Diabetes UK. Some 4.6 million have a diagnosis of diabetes, up from 4.4 million a year ago, and a record high. The vast majority, 90%, have type 2, the form that is linked to excess weight, and which tends to occur in middle age. (Type 1 is an auto-immune disease and tends to develop in childhood.) A further 1.3 million people are thought to be living with undiagnosed type 2 diabetes, and it is estimated that 6.3 million people have prediabetes, which means that their levels of blood sugar are so high that, without treatment, they risk developing type 2 diabetes. Separate research has found that, worldwide,…