The Difference Between Glycemic Index and Glycemic Load

Glycemic index (GI) and glycemic load (GL) are both measures that provide information about how different carbohydrate-containing foods can impact blood sugar levels. These tools can be useful for managing healthy blood glucose levels, supporting your weight loss journey, and even promoting overall health and wellness. While glycemic load and glycemic index are related, they convey slightly different information.

The glycemic index is a numerical scale that ranks carbohydrates in foods based on how quickly they raise blood glucose levels compared to a reference food (usually pure glucose or white bread). The scale typically ranges from 0 to 100, with higher values indicating a faster and larger increase in blood sugar levels. Foods with a low glycemic index (between 0 and 55 on the scale) cause a slower and more gradual increase in blood sugar. Furthermore, foods with a medium glycemic index (between 56 and 69) have a moderate impact on blood sugar, and foods with a high glycemic index (70 and above) cause a rapid and significant increase in blood sugar. 

On the other hand, the glycemic load takes into account both the quality (glycemic index) and quantity of carbohydrates in a specific portion of food. The glycemic load is calculated by multiplying the glycemic index of a food by the amount of carbohydrate in a serving and dividing by 100. Similar to the glycemic index, there is also a scale for glycemic load. Foods with a low glycemic load (between 0 and 10) have a low impact on blood sugar. Foods with a medium glycemic load have a moderate impact on blood sugar and are between 11 and 19 on the scale. Finally, high glycemic load foods have a numerical value of 20 and above and can cause a significant increase in blood sugar

How to use them:

• Glycemic Index (GI):

• Choose low-glycemic index foods to help manage blood sugar levels.

• Consider using the glycemic index to make choices within food categories (e.g., selecting whole-grain bread over white bread).

• Glycemic Load (GL):

• Provides a more practical approach by considering the serving size of a particular food.

• Helps in better understanding the overall impact of a specific amount of food on blood sugar.

• Combining both glycemic index and glycemic load can provide a more comprehensive view when making dietary choices.

One example of combining both the glycemic index and glycemic load is if we look at watermelon. Watermelon has a high glycemic index but a low glycemic load because it contains a small amount of carbohydrates per serving. This means that while it may cause a quick spike in blood sugar, the overall impact may be relatively low due to the small serving size.

Both glycemic index and glycemic load can be useful tools for individuals managing diabetes or those looking to make informed choices for overall health. However, it's essential to remember that other factors, such as individual metabolism and the presence of other nutrients in the food, also play a role in determining the overall impact on blood sugar levels. Always consult with a healthcare professional or a registered dietitian for personalized dietary advice. Schedule a complimentary call with one of our Ready Steps registered dietitians here!