What is the Glycemic Index?
The glycemic index is a ranking of carbohydrates based on their immediate effect on blood glucose (blood sugar) levels. It compares foods gram for gram of carbohydrate. Carbohydrates that breakdown quickly during digestion have the highest glycemic indexes. The blood glucose response is fast and high. Carbohydrates that break down slowly, releasing glucose gradually into the blood stream, have low glycemic indexes.
The glycemic index is about the quality of the carbohydrates, not the quantity.
Before the development of the glycemic index beginning in 1981, scientists assumed that our bodies absorbed and digested simple sugars quickly, producing rapid increases in our blood glucose level. This was the basis of the advice to avoid sugar, a proscription recently relaxed by the American Diabetes Association and others.
The glycemic index should not be your only criterion when selecting what to eat. The total amount of carbohydrate, the amount and type of fat, and the fiber and salt content are also important dietary considerations. The glycemic index is most useful when deciding which high-carbohydrate foods to eat. But don’t let the glycemic index lull you into eating more carbohydrates than your body can handle, particularly if you have diabetes. The number of grams of carbohydrate we consume is awfully important. Make sure you know the carbohydrate content of the foods you eat—study the nutritional information on the package.
