Fat intake and the development of type 2 diabetes

The increase in the number of patients with diabetes has become a worldwide healthcare issue, with numbers predicted to reach approximately 600 million by 2035. In Asia-Pacific region, the prevalence of type 2 diabetes has increased dramatically in recent decades, of which the major causes are believed to be modern lifestyle changes, e.g., Western dietary pattern and reduced physical activity, on their genetic basis of lower insulin secretory capacity. Particularly, in East Asian countries, the amount of fat intake has increased nearly three-fold over this half of century; dietary fat appears to be the major culprit of type 2 diabetes pandemic in East Asia. However, convincing evidence has not yet been provided as to whether high-fat diet causes type 2 diabetes in epidemiological cohort studies. Here, we summarize clinical studies regarding fat intake and type 2 diabetes, and animal studies on high-fat diet-induced diabetes including our recent works on the novel mouse lines (selectively bred diet-induced glucose intolerance-prone [SDG-P] and -resistant [SDG-R]) to address the etiology of high-fat diet-induced diabetes. These epidemiological and experimental findings would provide further insight into the etiology of type 2 diabetes under the modern nutritional environment, namely in the context of increased fat intake.