TNF and type 2 diabetes mellitus: It is possible that when visceral fat is excessively accumulated in the body, macrophages infiltrate around hypertrophic adipocytes, leading to the massive release of inflammatory factors (IL6, tumor necrosis factor) and the reduction of adiponectin, thereby reducing insulin sensitivity, and eventually showing insulin resistance and lipid metabolism disorders, and then developing metabolic syndrome and T2DM (30).