According to researchers at the CDC:
“After an almost 20-year increase in the national prevalence and incidence of diagnosed diabetes, an 8-year period of stable prevalence and a decrease in incidence has occurred. Causes of the plateauing and decrease are unclear but the overall burden of diabetes remains high and deserves continued monitoring and intervention.”
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Paleo Diabetic 
More people living a active lifestyle and eating a well balanced diet, ADA diet, has led to reduction in type2 diabetes.