What is the Glycemic Index and Should I use it with Carb Counting?
The glycemic index (GI) is a list of foods that details how various foods affect blood glucose levels. It was developed in the early 1980s by researchers who studies how quickly or slowly various carbohydrate-containing foods raised blood glucose – bread, corn, pasta, beans, fruit, and others. The GI research helped show that not all carbohydrates raise blood glucose levels the same amount. They showed, for instance, that potatoes raised blood glucose more quickly than fruit and that legumes raised blood glucose quite slowly.
This is valuable information, but it can be difficult for people with diabetes to use the GI for blood glucose control. That’s because the GI only evaluates one food at a time. Most people eat several foods in a meal, and some are high in carbohydrate and others are high in protein or fat. The combination of foods in a meal is what determines the effect on blood glucose. In addition, a number of other factors affect how quickly foods raise blood glucose, such as:
• How much blood glucose-lowering medication you take and the type of medication you take
• The fiber content of the foods you eat
• The ripeness of the fruit or vegetable you eat
• Whether the food is cooked or raw
• How quickly or slowly you eat
• The level of blood glucose before a meal (when the starting point is low, blood glucose rises faster after a meal)
• The time of your last dose of diabetes medication and the time you eat
Although the GI may not account for all of this, it can be another tool in your meal planning toolbox. As you progress with carb counting, you may develop your own personal GI. Your records may show that the carbohydrate in certain foods affects your blood glucose more than others. This information can help you fine-tune your blood glucose management.