Researchers say obesity is the main reason for the high rate of diabetes. More screenings and education are needed.

There’s no sugarcoating the findings.

More than half of the U.S. adult population has diabetes or prediabetes, according to a study in the current issue of the Journal of the American Medical Association (JAMA).

Between 2011 and 2012, an estimated 14 percent of U.S. adults were found to have diabetes. During the same time, about 38 percent of adults had prediabetes.

The diabetes rate for all American adults was about 27 percent higher in 2011-2012 than 1988-1994.

Nonetheless, data from recent years suggest that the increasing level of diabetes might be tapering, the organization reported.

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Meanwhile, another study done by researchers from the National Institutes of Health and the Centers for Disease Control and Prevention, which was published in the same issue of JAMA, showed more than half of Asian Americans and nearly half of Hispanic Americans with diabetes are undiagnosed.

At 51 percent, Asian Americans have the highest proportion of undiagnosed diabetes among all ethnic and racial subgroups studied. In all, 21 percent of that population had diabetes.

Hispanic Americans had the highest level of diabetes at nearly 23 percent. Of those, 49 percent were undiagnosed.

Andy Menke, Ph.D., epidemiologist at Social & Scientific Systems Inc. in Silver Spring, Maryland, said there is no clear-cut reason for these distinctions by race and ethnicity.

He theorized it may have something to do with differences in genetics, diet, and access to healthcare. Menke also attributed possible differences to cultural traditions regarding obesity.

Menke emphasized the need to better educate people on the risk factors of diabetes. Those factors include obesity, older age, and family history.

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Diabetes is a major cause of illness and death in the United States. The condition cost an estimated $245 billion in 2012, according to the American Diabetes Association.

Due to the rise in obesity in the U.S. over the past few decades, type 2 diabetes continues to be the most common form of diabetes. It accounts for 90 to 95 percent of those diagnosed, said Menke. Diabetes was up in every age, sex, education level, income, and racial/ethnic subgroup.

Yet, there was a bit of upbeat news. The proportion of people with undiagnosed diabetes dropped 23 percent between 1988-1994 and 2011-2012.

Menke and his team speculated the drop was due to public health policies aimed at improving access to care and increasing diabetes awareness.

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The large proportion of people with undiagnosed diabetes points to the need for increased screening and education, Menke said.

A previous study found that only 44 percent of U.S. adults and 39 percent of Hispanics had been screened for diabetes in the past three years, Menke pointed out.

That makes it all the more important to improve education about diabetes as well as increase access to healthcare. This is particularly true among groups such as Asian Americans, who might develop type 2 diabetes at a lower body mass than other ethnic groups, observed Menke.

Along those lines, obtaining more specific data on Asian and other subgroups may help pinpoint education and diagnosis efforts, he added.

Menke noted that additional studies that collect information on specific Asian heritages, such as Chinese or Indian, are also important.