The prevalence rate of diabetes mellitus has been rapidly risen becoming the major public health problem in the world due to complex interactions between diets, lifestyles, environment, and socioeconomic factors. The relevant studies were comprehensively searched through five electronic databases: PubMed, ScienceDirect, MDPI, Scopus, and Web of Science. The findings of the selected relevant studies were analyzed through a narrative synthesis approach to find out the significant trends and associations of dietary sugars, physical inactivity, and unequal access to health care with diabetes prevalence. Based on the findings of the relevant literatures reviewed, the prevalence and incident risk of type 2 diabetes is significantly associated to dietary sugars, physical inactivity, and unequal access to health care. Thus, dietary sugars, physical inactivity, and unequal access to health care have been documented as major risk factors for type 2 diabetes.