The prevalence rates of diabetes mellitus and its complications in South Asia are much higher than in other developed and developing countries; therefore, diabetes mellitus has become a serious problem in this region. While the prevalence of diabetes mellitus in South Asia is remarkable, its characteristics and causes have not been well-elucidated. More than 85% of the diabetic population in South Asia suffer from type 2 diabetes, and the causes can be divided into two categories: internal/traditional causes and causes induced by rapid development. Factors such as age, gender, diet and lifestyle changes, including a lack of physical activity caused by modernization and urbanization, are major contributory factors. The majority of the healthcare costs associated with diabetes are due to its later complications and are not preventable. Therefore, inexpensive treatment at an early stage of diabetes is important. In this review, the following are recommended as preventive measures of the incidence of the disease: (1) induction of UCP1 through the diet, (2) increasing the intake of antidiabetic bioactive components and/or food and (3) evolution of the consensus through educational programs and government policy. National strategies and interventions should be implemented immediately for both the primary and secondary prevention of diabetes mellitus and its complications in order to advocate healthy living among the South Asian populations.