When we eat carbohydrates, they are broken down into glucose which is absorbed into our bloodstream. On detecting glucose, the pancreas releases a hormone called insulin. Insulin tells our cells to open and let glucose in so that it can be used as energy. However, consuming excessive amounts of carbohydrates causes the blood glucose level to spike, thus triggering pancreas to release more insulin. If this continues over a period of time, the cells stop responding to insulin. As a result, glucose begins to buildup in our bloodstream, thus leading to various health related diseases.

Now, glycemic index is a measure that ranks carbohydrate-containing foods according to their effect on blood glucose levels. Foods low on glycemic index are broken down slowly. Hence, the blood glucose level remains stable, thus lowering the risk of diabetes, aiding in weight loss, etc. Examples of such foods include cashews, apples, lentils, etc.