Newly available 2011-2012 data from the very large National Health and Nutrition Examination Survey (NHANES) has revealed that Asian Americans have the highest proportion of undiagnosed diabetes among all ethnic and racial subgroups studied, at 51%. Diabetes was also common in Asian Americans, at 21%. The ethnic group with the highest prevalence of diabetes was Hispanic-Americans, at nearly 23%, with 49% of that undiagnosed.
One major reason for the high rate of undiagnosed diabetes among Asian-Americans may be that this group seem to develop type 2 diabetes at a lower body mass index than expected. The American Diabetes Association recommends Asian Americans get tested for diabetes at a BMI of 23 or higher, a lower threshold than the general population.
About 1 in 5 non-Hispanic black adults had diabetes, with 37% undiagnosed. Non-Hispanic whites had the lowest prevalence at 11%, and the lowest proportion of undiagnosed, at just over 32%.
However, overall the prevalence of diabetes has risen among American adults: from nearly 10% in 1988 to over 12% in 2012.