When you eat certain foods, particularly refined carbohydrates, that food is converted to sugar inside your body. Your body’s way of dealing with this sugar is to produce a hormone called insulin. Insulin is best thought of as a key, it unlocks the door allowing sugar to move out of the blood stream into your cells. This is where you need it, the cells use it for energy.
When working efficiently, this is a fantastic system that helps your body to function well. But when you have type 2 diabetes, prediabetes or significant abdominal obesity, that system does not work so well.
Eating too many refined carbohydrates elevates your insulin levels for long periods of time and your cells start to become resistant to the effects of insulin.
Dr Angus Ferguson explains in more detail in the video below.