One of the best examples of the major impact of environment on diabetes incidence is the increase in diabetes seen when immigrants enter the United States. This is especially true for non-Caucasian ethnicities, all of whom have a much higher genetic burden for type 2 diabetes than Caucasians. This increased genetic burden is often masked by the environment of emerging countries, where manual labor and lack of motorized transportation require increased physical fitness, and where food choices are often limited and sparse. There is also an under appreciated role of environmental pollutants and life stress. This report shows the effect of migration to the US on diabetes prevalence of the Hmong population in Wisconsin, most of whom left Laos and other Southeast Asian countries after the Vietnam war. They show a diabetes incidence 3.3 times higher than the comparable Caucasian population in Wisconsin, and a much higher prevalence than remaining Hmong population in Southeast Asia. An attractive hypothesis for the decreased genetic burden of diabetes in Caucasians was put forth by Jared Diamond, of Guns, Germs and Steel fame, who suggests that some of the diabetogenic genes in Caucasians were lost when food became more plentiful, and famines less common, in Western Europe, provoking an increase in type 2 diabetes at a time when there were no treatments, and thus a high mortality which resulted in removal of these genes from the population.