How Insulin Resistance Develops

Insulin resistance is the change that happens years before a Type 2 diabetes diagnosis. Understanding it explains almost everything else about the condition.

Picture insulin as a key and your cells as locked doors. When you eat, glucose enters your blood, your pancreas releases insulin, and the doors open so glucose can go inside and be used for energy.

With insulin resistance, the locks get stiff. The same amount of insulin no longer opens the doors properly. Your muscle, liver and fat cells stop responding the way they should.

Your pancreas notices that blood glucose is staying high, so it makes extra insulin to force those stiff locks open. This usually works. Your blood glucose stays normal, you feel completely fine, and a routine test shows nothing wrong. This stage can last for years.

The trouble is that the pancreas cannot keep this up forever. The cells that make insulin gradually tire out. Once insulin production starts falling behind, blood glucose begins to rise — first into the prediabetes range, then into diabetes.

This is why Type 2 diabetes is called gradual. By the time it is found, the process has usually been running quietly for a long time. It is also why acting early, even at the prediabetes stage, makes such a difference — the insulin-making cells still have something left to protect.