The Glycemic Index: A Tool for Controlling Blood Sugar
If you have diabetes, you may have heard or read about the “glycemic index.” What exactly is this? It’s one of the tools available to you that measures the effect specific carbohydrates have on your blood sugar levels.
A good goal most of the time, for people with and without diabetes, is to eat foods that don’t cause a quick rush of sugar into your bloodstream. That rise in your sugar level creates a need for a quick boost of insulin. If you don’t have diabetes, over time, that sugar overload can cause “insulin resistance,” in which your body begins to use insulin less efficiently. Insulin resistance is often an early sign that full blown diabetes will soon develop.
If you do have diabetes, you already have problems with the way your body uses insulin. As a rule, you don’t want to eat foods that cause a quick rise in blood sugar either.
Many people successfully use the glycemic index to make sure they eat carbohydrates that keep their blood sugar levels steady and avoid the carbs that cause rapid fluctuations in sugar levels. The glycemic index assigns numbers to foods, with the highest number being 100. Foods with higher numbers break down quickly during digestion and cause sugar to enter your bloodstream more quickly.
Basic principles of the glycemic index
The basic idea of controlling your blood sugar by understanding the glycemic value of carbohydrates is fairly simple. You don’t even have to know the numbers to understand the main concepts. To eat foods that break down slowly during digestion and release sugar into your bloodstream gradually, keep these goals in mind:
- Keep potatoes in your diet to a minimum. Even though potatoes are a vegetable, they have a high glycemic value and cause your blood sugar to rise fairly quickly.
- Eat breads that are made of whole grains. In other words, avoid white bread. Even bread that’s called simple “wheat” bread is not your best choice. You want to look for breads that are labeled “whole wheat,” “whole grain,” “10 grain,” etc.
- Choose meals that feature dried beans such as black beans, garbanzo beans, kidney beans, cannellini beans, etc.
- Choose breakfast cereals that are made of oats, barely and/or bran. These break down more slowly in your system.
- Be sure to include the following vegetables in your diet regularly: broccoli, cabbage, kale, Brussels sprouts, chard. These are called “cruciferous” vegetables, and they have a low glycemic value.
- Be sure to include the following fruits: tomatoes, apples, grapefruit, cherries, plums.
- Be aware that the following fruits and vegetables have a higher glycemic value, so these are the ones you’ll want to
limit: raisins, bananas, watermelon, potatoes, carrots, cantaloupe.
- As you might expect, sugary desserts and candies have a high glycemic value, so you definitely want to avoid these.
There are some professionals and diabetes educators who feel that the glycemic index is too complex to be helpful to non-medical people. After all, it might seem strange to think that you should limit foods like bananas, potatoes and cantaloupe. They’re fruits and vegetables with lots of vitamins and minerals, right? But the key here is the word “limit.” Fruits and vegetables with higher glycemic values will cause sugar to enter your bloodstream more quickly. You don’t have to stop eating them completely, but you’ll be better off limiting them and sticking with fruits and vegetables that have lower glycemic values.
It may be helpful to you to make an appointment with your doctor, diabetes educator or dietitian to talk about ways you can use the glycemic index to help you figure out the best food plan for you, based on when you exercise and what kind of exercise you do, your insulin requirements, etc. These professionals can teach you the ins and outs of the glycemic index. They can give you solid advice on whether the index is a helpful tool for you.
C. Guber. Carol Guber’s Type 2 Diabetes Life Plan. Broadway Books, New York, New York, 2002; National Institute of Diabetes and Digestive and Kidney Diseases.