Effective intervention for Type 2 Diabetes relies heavily on early detection. However, a majority of people with early-onset diabetes are not aware of their condition and are likely to consult with a physician only when their homeostatic control of blood sugar levels is irreparably damaged. Thus, there is a growing demand for screening tools that can easily be integrated into routine check-ups and do not require changes in daily routine and diet, doctor consults or laboratory analysis of blood samples. The screening tool we propose here is based on data gathered from Continuous Glucose Monitors and on a model of the blood glucose level as a function of glucose intake and the dynamics of the feedback control. We calibrate the method using data from a clinical trial with subjects diagnosed by a physician (n=123) and validate it on a larger follow-up study (n=270). Here we show that the sensitivity of the proposed test is on par with that of the HbA1c criterion and exceeds that of the Oral Glucose Tolerance Test.