The glycemic index of each food is determined by extensive testing, to measure its ability to raise blood sugar levels within a time period. They are then assigned a glycemic index number, which is related to the rate at which either white bread or glucose are absorbed by the body. (comparison)
For example, the Glycemic index of many breakfast cereals (which are highly refined), is much higher than sugar. Potatoes, which contain mostly simple starches, have a very high glycemic index. This means that eating these foods will have an adverse effect on a diabetic, causing a surge in blood sugar levels, and causing the corresponding surge in insulin, and storage of glucose as fat.
However, when low glycemic index foods are chosen, their complex nature requires a much longer process for the body to break them down into glucose. This extends the time required for digesting them, and therefore means that glucose will be released much more slowly, over a longer period of time. This also means that the body can utilize the sugars for bodily functions, instead of storing them as fats.
The ideal situation is that the diabetic is able to match his or her body's energy requirements with the rate of the release of glucose from these complex foods.
The glycemic index is not the only thing which must be considered when using this system.
"To predict and compare the overall blood glucose response to foods, we must calculate the glycemic load. To do this, we need to know both the G.I. value and the available carbohydrate content of the food (carbohydrates minus fiber). Next, calculate the glycemic load of each portion:
Glycemic load = [ grams of available carbohydrate per serving X G.I. ] / 100 .
Example:
A small banana contains 21 grams of available carbohydrate per serving, and has a G.I. value of 52.
GL = [ 21 X 52 ] / 100 = 10.9
A large appple contains 27 grams of available carbohydrate per serving and has a G.I. value of 38.
GL = [ 27 X 38 ] / 100 = 10.3
So the small banana has much the same effet as a large apple. Take your pick!!" 1. The previous quote and example was excerpted from Jennie Brand-Miller's website page: www.glycemicindex.com/index.html .
To use this very valuable method, you must know two things about your foods. You must know the glycemic index of the particular food, which is availble in many books, widely available, such as the "New Glucose Revolution" series, by Jennie Brand-Miller.(which we highly recommend for help in getting this concept in place in one's life. Some of these tables are available on her website:
The second thing you'll need to know is how many grams of carbohydrate are in each serving of the particular food in question. This information may be found at the following website: (this is part of the USDA website)
When looking at this page, scan down to the link "nutrient lists". Then, you can choose to have the display sorted for you either in alphabetical order, or in decreasing order of prevalence. If you or your friend have an internet connection, it would be a useful tool to have at your disposal. This site also explains how to order a C.D. of the newest food data base.
