What is the Glycemic Index?

High Glycemic FoodsHigh Glycemic Foods

What is the glycemic index?

By definition, the glycemic index (GI) is a way of comparing carb foods based on the immediate effect on blood sugar levels. The highest glycemic foods will release glucose almost instantly into the blood, while the lower glycemic items will take a much longer time to digest, and as a result, the glucose will be released more gradually into the bloodstream.

Range of values for glycemic index

The glycemic index has a range from 0 to 100, with 100 being pure glucose and 0 indicating no or negligible effect on blood sugar. In general, foods that have a glycemic index of 55 or below are considered lower glycemic foods, foods with a value between 56 and 69 are medium glycemic foods and those with a glycemic index value of 70 or above are high glycemic.

Click here for a printable copy of a list comparing low, medium and high glycemic foods.


Foods with no little or no effect

There are some foods that would score zero on the Glycemic Index scale, which means that they would have little or no effect on your blood sugar. These include the following:

Almonds, Artichokes, Avocados, Beef, Bok Choy, Brazil Nuts, Broccoli, Cabbage, Cauliflower, Celery, Cheese, Crab, Cucumber, Eggs, Fish, Hazelnuts, Lamb, Leafy vegetables, Lettuce, Lobster, Macadamia Nuts, Pork, Shrimp, Tuna and Walnuts.


Glycemic Index and Glycemic Load

The glycemic load is a concept that not only takes into account the GI value of the food, that is how quickly the food releases glucose into the bloodstream, but also the amount (in grams) of carbohydrate in the food. These two factors will determine not only how high the blood sugar level will rise, but also how long it will remain elevated. This is important, because the length of time the blood sugar remains high has an impact on health, both now and in the future.

Another way to describe glycemic load is that it takes into account the quantity of carbohydrate in the food as well as the quality. Where the GI only tells you the quality of the carb, the glycemic load value factors in the quantity of the carbs in the foods you are eating.

Low Glycemic Foods

We should note that experts can’t seem to agree on some of the exact GI values, due to different testing methods, food composition and physiology of individuals.


Do's and Don'ts based on the glycemic index

Do familiarize yourself in a general sense with high and low glycemic foods.

Do eat fruit, particularly bananas, when just ripe, but not overripe.

Do make oatmeal with old-fashioned or steel-cut oats.

Do choose whole-grain breads with seeds, cracked wheat, oats or other nuggets and made with a minimum of sugar.

Do snack wisely, choosing low-glycemic foods and combining carb foods with protein foods.

Do choose lower glycemic foods on a daily basis, including most vegetables, whole grains, legumes, nuts, seeds and many fruits.

Do enjoy smaller amounts of healthy higher glycemic foods, such as starchy vegetables and sweet fruits.

Do combine carbs at breakfast, especially high-glycemic carbs with healthy protein foods.

Do eat a balanced diet made up of a variety of vegetables, fruits, legumes, nuts, seeds, whole grains, low-fat dairy, lean meats and monounsaturated fats.


Don't add extra sugar to cereal and fruit.

Don't consume large amounts of high-glycemic foods, even healthy ones.

Don't choose instant oatmeal.

Don't include white bread and products made from white flour as a regular part of your diet.

Don't eat higher glycemic foods, even healthy ones, without adding some protein food or healthy fat.

Don't drink sugary fruit drinks and soft drinks.

Don't skip carbs altogether or radically limit them, especially healthy ones.

Don't get so fixated on the make-up of your food that you forget to enjoy it!


Health benefit

Research has shown that emphasizing lower glycemic carbs in your diet is correlated with less risk of disease.

However, there does not seem to be any benefit to your health shown by simply eating low-carb. This is partly because many lower-glycemic foods, such as vegetables and fruits, seem to provide protection against disease, because of their high nutrient content, including vitamins, minerals, fiber and phytochemicals .


PAGE SUMMARY for What is the Glycemic Index

-The glycemic index (GI) is a way of comparing carb foods based on the immediate effect on blood sugar levels.

-The glycemic index has a range from 0 to 100, with 100 being pure glucose and 0 indicating no or negligible effect on blood sugar.

-The glycemic load is a concept that not only takes into account the GI value of the food, that is how quickly the food releases glucose into the bloodstream, but also the amount (in grams) of carbohydrate in the food.

-Research has shown that emphasizing lower glycemic carbs in your diet is correlated with less risk of disease.


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