What is the main function of insulin?

Insulin is a hormone produced by the pancreas that helps to regulate the levels of glucose (sugar) in the blood. When we eat, our digestive system breaks down carbohydrates into glucose, which is then absorbed into the bloodstream. In response to the rise in blood glucose levels, the pancreas releases insulin into the bloodstream. Insulin acts as a key that unlocks the cells, allowing glucose to enter and be used as energy.