Is Britain's Diabetes Epidemic Under Control?

4.3 million people in the UK have been diagnosed with diabetes, and an estimated 850,000 more have the condition but do not know it. Nine in ten cases are Type 2, driven predominantly by weight, inactivity, and metabolic risk. The NHS spends around £10 billion a year on diabetes — roughly 10% of its entire budget — covering drugs, monitoring, consultations, and the treatment of complications that adequate management could have prevented. Those complications include 22,000 diabetes-related amputations every year and a leading claim on working-age blindness. The UK sits seventh in Europe for diabetes prevalence, a position that reflects both an ageing population and decades of rising obesity rates. The condition is not a background fact of modern life; it is a system under pressure that is failing to contain a preventable epidemic.

Around 80% of the risk for Type 2 diabetes is attributable to being overweight or obese — but that figure does not tell the whole story. South Asian communities in the UK develop Type 2 at significantly lower BMI thresholds than the white population and on average a decade earlier, a difference with important implications for screening and prevention thresholds. Deprivation is a powerful independent predictor: people in the most deprived quintile are twice as likely to develop Type 2 diabetes as those in the least deprived. The NHS Diabetes Prevention Programme, which refers high-risk individuals to structured lifestyle interventions, now reaches around 200,000 people a year and its own evidence shows 37% of completers avoid progressing to a diagnosis. That is a substantial effect — but the programme currently reaches a fraction of those eligible, and referral rates vary widely by GP practice and region.

Once diagnosed, the goal of diabetes management is keeping blood glucose within a target range to prevent complications. The standard measure is HbA1c, a marker of average blood sugar over roughly three months. Nationally, 68% of people with Type 2 diabetes meet their HbA1c target — which means nearly a third do not. But blood sugar control is only part of the picture. NHS England's “care processes” — eight checks including foot examination, retinal screening, and kidney function tests — are completed in full for only 39% of patients nationally, a figure that has not improved significantly in years. Diabetic ketoacidosis, a serious and potentially fatal complication, accounts for tens of thousands of emergency admissions annually, many of which are preventable with better day-to-day management and earlier intervention. Mental health comorbidity — depression and anxiety are significantly more prevalent in people with diabetes — is common and consistently under-treated.

Type 1 diabetes affects around 400,000 people in the UK and is an autoimmune condition, not a lifestyle disease. It has nothing to do with weight or diet: the immune system destroys the pancreatic cells that produce insulin, and without continuous external insulin management it is fatal. Technology has transformed what good management looks like: continuous glucose monitors (CGMs) provide real-time blood sugar data, and hybrid closed-loop systems — which automatically adjust insulin delivery — are reducing HbA1c levels and time-in-hypoglycaemia in clinical trials. NICE has recommended these devices, and NHS England committed to making hybrid closed-loop systems available to all eligible Type 1 patients by 2025. Supply chain constraints, workforce capacity to train users, and variation in local commissioning mean the rollout is behind schedule. Access currently correlates with where someone lives and how assertively they can advocate for themselves.

The National Diabetes Audit is one of the more comprehensive clinical audits in the NHS, but it does not cover all GP practices, and data completeness varies significantly by region — limiting confidence in local-level comparisons. Estimates of undiagnosed prevalence rely on modelling from survey data and risk-factor populations rather than direct population screening, meaning the 850,000 figure carries real uncertainty. Complications data — amputations, blindness, kidney failure attributable to diabetes — is collected inconsistently across primary and secondary care, making it difficult to track whether prevention efforts are producing measurable downstream reductions. Dietary and physical activity data, central to understanding Type 2 risk at a population level, relies on self-reported surveys that systematically underestimate food consumption and overestimate exercise, particularly in higher-weight populations. The audit is improving, but the picture it provides remains incomplete.