Diabetes costing world $850 billion a year

The number of people living with diabetes has tripled since 2000, pushing the global cost of the disease to $US850 billion a year, medical experts says.

The vast majority of those affected have type 2 diabetes, which is linked to obesity and lack of exercise, and the epidemic is spreading particularly fast in poorer countries as people adopt Western diets and urban lifestyles.

The latest estimates from the International Diabetes Federation mean that one in 11 adults worldwide have the condition, which occurs when the amount of sugar in the blood is too high.

The total number of diabetics is now 451 million and is expected to reach 693 million by 2045 if current trends continue.

The high price of dealing with the disease reflects not only the cost of medicines but also the management of a range of complications, such as limb amputations and eye problems.