ObjectivesThis review summarizes the burden and emerging risks of type-2 diabetes and prediabetes in South Asian populations and reviews recent evidence regarding diabetes prevention through lifestyle modifications among South Asians worldwide. We highlight gaps and discrepancies in the current literature, indicate opportunities and consider implications for future research in this area.FindingsRandomized, controlled trials along with major cohort studies and implementation research have demonstrated lifestyle intervention as an effective, cost-effective, and feasible method for reducing diabetes and prediabetes and their associated risk factors in South Asians, a population at high diabetes risk even of early age onset and with lower body mass index (BMI). However, there is a lack of evidence as to the best methods of diabetes prevention in normal-weight South Asians across age groups as well as individuals with impaired fasting glucose. Future prevention research should also aim to improve community-level education and implementation, ensure individual uptake, and dissemination of proven programs, design culturally tailored programs; and assess long-term outcomes of interventions.