The glycemic index (GI) categorizes how quickly your blood sugar will be affected by certain carbohydrates. Foods low on the glycemic index will take longer to break down and cause minimal increases in your blood sugar. However, foods high on the glycemic index break down very fast, increasing blood sugar quickly. The foods that are rated in the glycemic index above 70 are considered high and the foods that fall below 55 are considered low. The goal is to consume foods that are low on the glycemic index.
The Glycemic Load (GL) takes into account the glycemic index but also looks at how much of a specific carbohydrate is in one serving of a particular food. The more processed the grain, the higher it is on the glycemic load. The goal is to purchase whole grains with minimal ingredients that have a low glycemic load. Foods above 20 are considered high for the glycemic load and foods that fall below 10 are considered low. The Glycemic Load may be more useful than the Glycemic Index because it takes into account portion size as well as the quality of the carbohydrate.