The number of Americans with diabetes will double in the next 25 years, leading to health spending of $336 billion US, a new study suggests.

The number of people with the disease is projected to grow to 44 million in 2034 from 23.7 million in 2009. And while the population with diabetes doubles, the costs to treat the disease will triple, costing Medicare $171 billion, up from $5 billion currently. These figures do not factor in a rise in obesity among Americans.

In Canada, approximately 1.8 million, or about one in 18 people, had diagnosed diabetes according to the Public Health Agency of Canada in 2004-05. The prevalence of the disease increased by 24 per cent between 2000-01 and 2004-05, and the Canadian Diabetes Association predicts there will be three million Canadians living with the disease by 2010.

Researchers at the University of Chicago created a model to determine the cost burden of diabetes on society, which factored in trends in risk factors for the disease, its history and the effects of treatments.

Those studied were between 24 and 85. The findings are published in the December issue of the journal, Diabetes Care.

"Without significant changes in public or private strategies, this population and cost growth are expected to add a significant strain to an overburdened health-care system, write the authors. "We will find ourselves in a lot of trouble as a population."

The authors say their dire projections are based on the fact that earlier studies failed to represent the scope of the problem, projecting numbers that have already been surpassed.

For example, they cite one study from 1991 that predicted that the number of diabetics would double between 1987 and 2030 — from 6.5 million to 11.6 million. The projected 2030 figure is less than half the cases reported in 2009.

The researchers add that their prediction may be too conservative.

On a more positive note, the authors believe that obesity may level out in the next 10 years and then begin to decline, from 30 per cent in 2009 to 27 per cent by 2033.

"We anticipate that the population will reach an equilibrium in obesity levels, since we cannot all become obese," write the authors.