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Nutrition Content Questions


Understanding the Glycemic Index
The Glycemic Index rates foods based on how they affect blood sugar levels.
The Glycemic Index rates foods based on how they affect blood sugar levels.

Q. What is the glycemic index? Is it useful in managing diabetes?

A. The Glycemic Index (GI) rates foods based on how they affect blood sugar levels. In the 1980s, researchers began tracking how quickly various foods raise blood sugars. The GI score compares foods to white sugar. (White sugar ranks a GI score of 100.) Many people believe that knowing the GI scores of foodstuffs helps them control blood sugars.

Some foods do raise blood sugars quickly, such as white potatoes. But few people eat potatoes without eating anything else (even potato chips contain fat calories). The food combinations within the entire meal or snack will affect the total blood sugar response.

Fiber content, whether the food is cooked or ripened, the degree of processing, and portion sizes are not factored into the GI. Yet these other factors also influence the glycemic response.

According to the American Diabetes Association, the total amount of carbohydrate consumed is more important than the individual food source. Other influences on blood sugars include exercise, stress, time of day, and overall health.

However, it may be useful to develop a personal Glycemic Index. Certain foods may raise your blood sugars very quickly. In that case, just limit your intake or avoid those foods altogether.

Remember that dietary choices should be made with the guidance of a certified diabetes educator, doctor, or other health professional. The goal of meal planning is to eat a wide variety of foods in portions adequate to maintain good nutrition, as well as proper body weight and blood sugar control.

For more information on nutrition and food labeling, see:


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