Britain is in the grip of a diabetes epidemic that threatens to overwhelm the NHS and could lead to the first fall in life expectancy in 200 years.
The number of cases diagnosed has doubled in a year, figures out today will show. Family doctors recorded an extra 167,000 sufferers last year, compared with a rise of 83,000 in 2006-7.
The increase brings to almost 2.5 million the number of British diabetics. A further 500,000 people are thought to be affected but unaware of their condition. The condition shortens lives by 10 years and is a leading cause of circulatory problems and blindness.
The soaring rate of diabetes is driven by rising obesity. Today's figures from Diabetes UK show five million people are registered as obese by their GPs, up from 4.8 million in 2006-07. At least a million more Britons are predicted to succumb to diabetes by 2010.
Professor Sir George Alberti, a Government adviser and former head of the International Diabetes Federation, said the accelerating increase was partly due to improved screening but also to a genuine rise in cases.
"It is a clarion call for society to take this seriously," he added. "The catastrophe has started to happen. The Government has begun to tackle obesity and inactivity but converting good words into action is very difficult. It will take ages to have an effect."
The World Health Organisation has predicted that deaths from diabetes in Britain would rise from 33,000 a year in 2005 to 41,000 by 2015 but Professor Alberti said that figure underestimated its true impact. More than 80 per cent of sufferers die from heart attacks or strokes and more than 1,000 a year suffer kidney failure requiring dialysis.
"The WHO figure [for deaths] was very conservative," he said. "Large numbers die from heart disease and strokes [linked with diabetes] and they do not include those."
Diabetes is spreading around the world, fuelled by increasing urbanisation and the spread of Western lifestyles. It is estimated to have killed 2.9 million people in 2000, equivalent to the number of Aids deaths, although it has received a fraction of the attention. From 170 million people affected in 2000, doctors predict the total will rise to 370 million by 2025, leading to an epidemic of blindness and amputations.
Researchers have warned that the increase in diabetes and other chronic diseases driven by rising obesity could lead to a fall in general life expectancy. Writing in the New England Journal Of Medicine in 2004, Jay Olshansky and colleagues at the University of Illinois said life expectancy could be cut by five years in the coming decades if obesity continued to increase. Douglas Smallwood, chief executive of Diabetes UK, said: "These are truly alarming figures. Part of why we have seen such a huge increase can be attributed to improved screening from healthcare services and greater awareness amongst those at high risk of type 2 diabetes. However, there is no getting away from the fact that this large increase is linked to the obesity crisis.
"Diabetes is one of the biggest health challenges facing the UK. It causes heart disease, stroke, amputations, kidney failure and blindness and more deaths than breast and prostate cancer combined. The NHS already spends £1m an hour on diabetes. The soaring diabetes prevalence will continue to put a massive strain on an already struggling NHS and, unless it can respond, people's health could spiral downwards. We need to do all we can to raise awareness of the seriousness of diabetes and help people understand how a healthy lifestyle can help reduce their risk."
Diabetes is a disorder in the metabolism of carbohydrate, leading to excessive thirst and the production of large amounts of urine caused by lack of insulin. Nine out of 10 sufferers have Type 2 diabetes, which usually affects older people but is now seen in younger people and children as weight has risen. The risk is 10 times higher in those who are obese, defined as having a body-mass index of more than 30.
Diabetes: The risks, the costs
*The condition causes blood-sugar levels to rise because of a lack of insulin. The risk is 10 times higher in people who are obese.
*Raised sugar levels lead to high blood pressure, increased risk of heart attack, stroke, blindness, kidney damage and ulceration of the feet.
*It costs the NHS £1m an hour to treat. One pound in every £10 spent on the hospital service is for diabetes and its complications.
*Type 2 diabetes can be treated by diet and exercise and the effects are reversible if the damage has not gone too far.
*In more severe cases, drug treatment with tablets or injections of insulin is necessary.
*For up to 10 years, there are no symptoms, but doctors believe that the earlier that treatment begins, the less damage it causes.