If Americans don't eat better and exercise more, diabetes cases will double by 2034 and costs to care for the patients will triple, according to a new report that paints a bleak picture of the future.

With diabetes, the body fails to metabolize glucose, or blood sugar. Diabetes is the leading cause of amputations, blindness, and end-stage kidney disease.

Obesity, poor diet and lack of exercise are all known factors that have contributed to an already serious increase in type 2 cases, the variety that is largely preventable and comprises about 95 percent of all diabetes cases.

One example of how out of control the situation has become: A 1991 study projected U.S. diabetes cases would double, from 6.5 million in 1987 to 11.6 million by 2030. We're already at 23.7 million cases.

"If we don't change our diet and exercise habits or find new, more effective and less expensive ways to prevent and treat diabetes, we will find ourselves in a lot of trouble as a population," said the study's lead author Dr. Elbert Huang, assistant professor of medicine at the University of Chicago.

The study is detailed in the December issue of the journal Diabetes Care.

It projects costs associated with the disease will rise from $113 billion per year now to $336 billion by 2034, even with no increase in the prevalence of obesity. The researchers project that obesity rates will level off. If that doesn't happen, even more cases of diabetes will develop, they say.

Much of the increase in cases and in costs will be driven by aging baby boomers, the 77 million Americans born between 1946 and 1957 who are approaching the age of retirement. Because diabetes is now diagnosed earlier in life and treatments are more effective, people with the disease live longer.

"This leads to a longer history of disease, opportunities for more aggressive therapies, and time to accumulate complications, which are costly to treat," the researchers said in a statement.

Boomers are generally less healthy (and less happy) than the previous generation. Half of Americans aged 55-64 have high blood pressure, a major risk factor for heart disease and stroke, according to a 2005 report from the Centers for Diseases Control and Prevention.

"The public policy implications are enormous," said co-author Michael O'Grady, senior fellow at the National Opinion Research Center at the University of Chicago. "This is a serious challenge to Medicare and every other health plan in the country. The cost of doing nothing is the significant increase in the pain and suffering of America's population and a financial burden that will threaten the financial viability of public and private insurers alike."