From the NDIC (2005 data):
Hispanic/Latino Americans: After adjusting for population age differences, Mexican Americans, the largest Hispanic/Latino subgroup, are 1.7 times as likely to have diabetes as non-Hispanic whites. If the prevalence of diabetes among Mexican Americans was applied to the total Hispanic/Latino population, about 2.5 million (9.5 percent) Hispanic/Latino Americans aged 20 years or older would have diabetes. Sufficient data are not available to derive estimates of the total prevalence of diabetes (both diagnosed and undiagnosed diabetes) for other Hispanic/Latino groups. However, residents of Puerto Rico are 1.8 times as likely to have diagnosed diabetes as non-Hispanic whites in the United States.
Why do you think this is? Why are Hispanics more likely than non-Hispanic white people in the US to be diabetic?