American Council on Exercise by American Council on Exercise

The glycemic index (GI) is a measure of how a carbohydrate-containing food affects blood sugar levels. Based on its value from 0-100, a food is considered to have a high, medium, or low GI. Having a basic understanding of this concept will allow you to select foods that lead to a healthier, more energized you.

  1. Know the difference. Foods with a higher GI (for example- white bread) are quickly digested, which makes the blood sugar rise and fall rapidly. This can make you feel tired, hungry, and cranky. Lower GI foods, on the other hand, are digested slowly and keep blood sugar levels steady. Foods from this category give you more energy and help you feel full in between meals. 
  2. 2.Experience better health with a low GI diet. A diet rich in low GI foods has these proven health benefits: 
  3. Chose wisely. Include low to medium GI foods in your diet as often as possible. 
  4. Don’t shun all high GI foods. A high GI doesn’t necessarily mean a food is “bad” or unhealthy. You can still include high GI fruits and vegetables as part of your healthy diet. You should make it a point though, to avoid processed foods as much as possible—these generally have a higher GI (and are high in fat, calories, and/or bad carbs). 
  5. Be aware of “glycemic load” and portions. Some experts feel that glycemic load (GL) is a better way to measure a food’s effect on blood sugar because it counts how much of the carbohydrate you are eating. Like GI, lower glycemic loads are better. Use this equation to calculate GL:

    Glycemic load= GI/100 x grams of carbohydrate

If you would rather not get into calculations, simply choose foods with a lower glycemic index or load and eat reasonable portion sizes. 

Additional Resources

American Council on Exercise

American Diabetes Association

The University of Sydney

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