I. Introduction and PurposeDiabetes mellitus, or simply diabetes, is a disorder in which the body is unable to fully utilize converted energy from food. There are three types of diabetes: type 1 or insulin-dependent diabetes, type 2 or adult-onset diabetes, and gestational diabetes (Webmd.com, 2014). According to the American Diabetes Association, in 2011 there were approximately 25.8 million cases of diabetes. in the United States, of which 7 million were undiagnosed, and approximately 79 million cases of prediabetes (American Diabetes Association, 2014). They also report that diagnosed cases of diabetes cost the United States nearly $250 billion in 2012 (American Diabetes Association, 2014). With such a high prevalence of cases as well as staggering associated costs, it is clear that research into the risk factors and causes of diabetes is warranted. Diet and exercise have long been associated with diabetes risk, but recent studies show that environmental factors, including air pollution, may play a role in the development of diabetes, particularly long-term diabetes. type 2. A medical journal published in 2012 notes that "there are now at least six published epidemiological studies showing some degree of association between [particulate matter] (PM) or traffic-related air pollutants and [diabetes mellitus ] (DM). At least two other studies have demonstrated a relationship between ambient levels of air pollutants and markers of insulin sensitivity in humans… Although not all results from all studies have been positive, taken together, the The majority of observations support an association between air pollution, particularly road traffic. -linked sources and DM” (Rajagopalan & Brook, 2012).II. MethodsArticle searches were performed using data...... middle of article ......t causing insulin resistance in hyperlipidemic mice. Circulation Research, 104 (8), pp. 961-968. Sun, Q., Yue, P., Deiuliis, JA, Lumeng, CN, Kampfrath, T., Mikolaj, MB, Cai, Y., Ostrowski, MC, Lu, B., Parthasarathy, S. et al. (2009) . Ambient air pollution exaggerates adipose inflammation and insulin resistance in a mouse model of diet-induced obesity. Circulation, 119 (4), pp. 538--546.Webmd.com. (2014). Diabetes mellitus: types, symptoms, causes, treatments. [online] Retrieved from: http://www.webmd.com/diabetes/types-of-diabetes-mellitus [Accessed: March 15, 2014]. Xu, X., Liu, C., Xu, Z., Tzan , K., M. Zhong, A. Wang, M. Lippmann, L. Chen, S. Rajagopalan, and Q. Sun. Long-term exposure to ambient pollution by fine particles induces insulin resistance and mitochondrial damage in adipose tissue. Toxicological Sciences, 124 (1), pp.. 88--98.