These two tools are overlooked by most low carbohydrate diet proponents. Without these indices, using the Glycemic Index to compare foods is like comparing apples to oranges. The GI number for a food doesn't predict the Insulin Score of a food, since protein and fat in foods also affect the body's insulin production and response. Protein stimulates insulin production and fats magnify the insulin effect. Both of these ingredients have a relatively low effect on blood sugar. Therefore, a diet rich in low GI foods which is high in protein and fat increases insulin secretion too. In other words, there is no connection between a food's GI numbers and Insulin Score numbers.

Foods with a high GI number can also differ dramatically in calories and carbohydrate amount. Let's look at potatoes and white bread, two foods with a high GI number. The white potato has 450 calories per pound, while white bread has 1300 calories per pound. You must eat many more potatoes to equal the same carbohydrate introduction as bread.

The Satiety Index measures how satisfied you feel after you consume a food. When you are satiated, or satisfied, you will consume fewer calories in the course of a day. Foods higher in Satiety Index can reduce your caloric intake overall. Guess which food has scored the highest in the Satiety Index? The potato, vilified in high protein/low carbohydrate diet plans because of its high GI numbers.

Measuring the Glycemic Index of foods in real life is very complicated. When you eat more than one food at a time, the Glycemic Index number of the individual food is changed. For instance, baked potatoes have a GI number of 85, while french fries have a GI number of 75 (on the glucose-relative scale). The fat used in cooking the french fries changes the GI number of the potatoes. The rate at which your stomach processes food and empties also makes a difference in the effect on your own blood sugar levels. Unless you are regularly testing your blood sugar, as diabetics do, you can't be sure how high GI number foods affect your own body.

A Mars candy bar is a good example of why the Glycemic Index numbers alone aren't a good measure of nutrition. The candy bar has a lower GI number than white bread, rice, and potatoes because it has much more fat. However, that fat magnifies the insulin response of the body, so the Insulin Score of a Mars bar is actually higher than bread or rice or potatoes. And no one would assume that a Mars bar has more nutrition than a baked potato.

There is one useful conclusion that can be derived from learning about foods with a high Glycemic Index number. Highly processed foods with high GI numbers can cause changes in the body that lead to overeating. Overeating and consuming too many calories are more closely correlated with developing diabetes and other diseases than the GI scale alone.