Glycemic load considers the quality and the quantity of carbohydrate content of the foods. Glycemic index takes into account the quality of the carbohydrate in a food and ignores its quantity. A glycemic index value therefore tells us only how rapidly a particular carbohydrate turns into sugar. It doesn't tell how much of that carbohydrate is in a serving of a particular food. Both the things are important to understand a food's effect on blood sugar.
Glycemic Load = GI x carbohydrate/100
Take watermelon as an example of calculating glycemic load.
The glycemic index = 72
In a serving of 120 grams, it has 6 grams of available carbohydrate.
The glycemic load = (72/100) x 6 = 4.32 = 4 rounded.
By simply looking at the glycemic index value you will think that watermelon is not good for you, but its glycemic load is low, so it is safe to eat.
The glycemic index value alone does not give accurate picture of the food. The glycemic load (GL) takes both the things into account.
The glycemic load is the glycemic index divided by 100 multiplied by its available carbohydrate content (i.e. carbohydrates minus fiber) in grams.
Foods that have a low glycemic index invariably have a low GL, while foods with an intermediate or high glycemic index range from very low to very high GL. Therefore, you can reduce the GL of your diet by limiting foods that have both a high glycemic index and a high carbohydrate content.
To optimize insulin levels, you should eat fruits, vegetables, and whole grains preferably with low glycemic index and low GL values. The fiber contained in these foods slows down the release of sugars.
The following table gives a values for low, medium and high glycemic load for foods.
|Value||Glycemic Index (GI)||Glycemic Load (GL)|
|High||70 or more||20 or higher|
|Medium||56 to 69 inclusive||11 to 19 inclusive|
|Low||55 or less||10 or less|
Values are with reference to Glucose.
Foods that have a low glycemic index invariably have a low glycemic load, while foods with an intermediate or high glycemic index range from very low to very high glycemic load. Therefore, you can reduce the glycemic load of your diet by limiting foods that have both a high glycemic index and a high carbohydrate content.