The glycemic index (GLYX table) is used as a measure of the blood sugar level triggered by particular foods. It is a worldwide standard in ranking carbohydrates in terms of their influence on blood sugar levels after eating. A food is considered good for weight reduction when it triggers a low blood sugar level and thus a low insulin level. The hormone insulin not only lowers blood sugar levels, it also stops fat burning at the same time. This is why when it comes to losing weight, it is particularly important to eat only foods that produce a low blood sugar level.
However, the carbohydrate concentration of a food -- that is, how many grams of carbohydrates a particular food contains -- also plays an important role. When a food has less than 10 grams (.35 ounces) per 100 grams (3.5 ounces) in carbohydrate concentration, then foods with a high glycemic index may also be eaten. Such high glycemic foods are marked with an asterisk* in the carbohydrate table. For example, watermelon has a glycemic index value of 75 and would be considered a poor choice for a weight-loss diet. But since its carbohydrate content comes in at only 7 grams per 100 grams of watermelon, it can be eaten without guilt and without negatively affecting the body's insulin level.
- Low glycemic index < 55
- Mean glycemic index 56-69
- High glycemic index > 70