Diabetes, a comprehensive genetic disease, is principally due to the deregulation of glucose levels in theblood. In addition to contemporary epidemiological studies, systematic substantiation suggests that long-termdiabetes leads to cancers due to a variety of reasons. In this study, blood samples were collected with informedconsent from confirmed type I diabetic (T1DM, n=25) and type II Diabetic patients (T2DM, n=25) with equalnumbers of controls. Further depending on the lifestyle habits they were subdivided into smokers/non-smokersand alcoholics/non-alcoholics. Chromosomal assays were performed for these cases and it was found that therewas a significant increase in chromosomal aberration frequency in diabetic patient groups who are exposed tosmoking and alcohol than that of normal diabetic groups (T1DM and T2DM). On the other hand, patient groupswho were non-smoking and non-alcoholics also showed higher chromosomal aberrations when compared to thatof controls. While the mechanisms for these increased chromosomal aberrations in diabetic groups are not clear,they may be due to increased oxidative stress leading to oxidative damage and resulting in genomic instability,which in turn may contribute to an increased risk for cancer.