If your cells become too resistant to insulin, it leads to elevated blood glucose levels (hyperglycemia), which, over time, leads to prediabetes and Type 2 diabetes.
In type 2 diabetes, the pancreas makes insulin, but the cells don't respond to it as they should. This is called insulin resistance. When glucose can't get into cells, the blood sugar level rises.
This effect is seen with fasting periods as short as 24-36 hours. Longer duration fasts reduce insulin more dramatically.
It lowers blood glucose levels by removing the exogenous glucose from the blood stream
With too little insulin, the body can no longer move glucose from the blood into the cells, causing high blood glucose levels.