Inflammatory response
Studies suggest that abdominal fat causes fat cells to releases ‘pro-inflammatory’ chemicals, which can make the body less sensitive to the insulin it produces by disrupting the function of insulin responsive cells and their ability to respond to insulin.
This is known as insulin resistance - a major trigger for type 2 diabetes.
Having excess abdominal fat (i.e. a large waistline) is known as central or abdominal obesity, a particularly high-risk form of obesity.