Even people with a normal weight who have excess belly fat are at 2.75 times the risk for cardiovascular death and 2.1 times the risk of all cause mortality according to researchers at the Mayo Clinic. Information from the NHANES study showed that an abnormal waist to hip ratio is a powerful predictive statistic. Abdominal fat is correlated with the metabolic syndrome, which is the precursor of type 2 diabetes, and is associated with insulin resistance, high blood pressure, increased cholesterol and triglycerides, and increased conversion of glucose into fat.
An interesting consideration is that the visceral fat is stored in the omentum, which is an organ that regulates immune T-cells, healing, and regeneration. Perhaps there is a relationship between the omentum function and the development of type 2 diabetes.