Oct. 30, 2008 -- Scary Halloween news from the CDC: Type 2 diabetes is up 90% since 1997.

And that may be an underestimate because the numbers come from self-reported surveys conducted by the CDC in 1995-1997 and in 2005-2007. About a third of people with diabetes don't yet know they have the dangerous disease.

"This dramatic increase in the number of people with diabetes highlights the increasing burden of diabetes across the country," CDC data analyst Karen Kirtland, PhD, says in a news release.

For the first time, the CDC has state-specific data on diabetes. Southern states have the highest diabetes rate. Among the 10 states with the highest diabetes rates, only Arizona is not in the South. The other nine are Alabama, Florida, Georgia, Kentucky, Louisiana, South Carolina, Tennessee, Texas, and West Virginia.

West Virginia takes the dubious honor of being the U.S. diabetes capital. Of the 33 states for which the CDC has complete data, West Virginia has the highest annual diabetes rate -- 12.7 new diabetes cases for every 1,000 residents.

Minnesota has the lowest annual diabetes rate: five new cases per 1,000 residents. But even in the "best" state, diabetes is way up -- by 67% -- over the last decade.

California has the highest number of new diabetes cases. In 1997, 208,000 Californians were told they had diabetes.

What's going on?

"The growth in diabetes prevalence has been concomitant with growth in obesity prevalence," Kirtland and colleagues report in the Oct. 31 issue of Morbidity and Mortality Weekly Report.

In the South, 27.3% of people are obese. But Americans aren't exactly lean in other regions. The obesity rate is 26.5% in the Midwest, 24.4% in the Northeast, and 23.1% in the West.

Obesity, the CDC says, is the major risk factor for diabetes. Yet it's not necessary to become thin to avoid this debilitating disease.

A study of people at high risk for diabetes shows you can cut your risk of diabetes by 58% in a three-year period by doing just two things: