OBJECTIVEAsian Americans manifest type 2 diabetes at low BMI levels but may not undergo diagnostic testing for diabetes if the currently recommended BMI screening cut point of 25 kg/m(2) is followed. We aimed to ascertain an appropriate lower BMI cut point among Asian-American adults without a prior diabetes diagnosis.RESEARCH DESIGN AND METHODSWe consolidated data from 1,663 participants, ages 45 years, without a prior diabetes diagnosis, from population- and community-based studies, including the Mediators of Atherosclerosis in South Asians Living in America study, the North Kohala Study, the Seattle Japanese American Community Diabetes Study, and the University of California San Diego Filipino Health Study. Clinical measures included a 2-h 75-g oral glucose tolerance test, BMI, and glycosylated hemoglobin (HbA(1c)).RESULTSMean age was 59.7 years, mean BMI was 25.4 kg/m(2), 58% were women, and type 2 diabetes prevalence (American Diabetes Association 2010 criteria) was 16.9%. At BMI 25 kg/m(2), sensitivity (63.7%), specificity (52.8%), and Youden index (0.16) values were low; limiting screening to BMI 25 kg/m(2) would miss 36% of Asian Americans with type 2 diabetes. For screening purposes, higher sensitivity is desirable to minimize missing cases, especially if the diagnostic test is relatively simple and inexpensive. At BMI 23 kg/m(2), sensitivity (84.7%) was high in the total sample and by sex and Asian-American subgroup and would miss only approximate to 15% of Asian Americans with diabetes.CONCLUSIONSThe BMI cut point for identifying Asian Americans who should be screened for undiagnosed type 2 diabetes should be <25 kg/m(2), and 23 kg/m(2) may be the most practical.