Glycemic Index 101
The Glycemic index is a measure of how high your blood sugar rises after eating a fixed amount of carbohydrate. It is expressed in the form of number that gives an estimate of how quickly that food is converted to sugar in our bodies. Glucose is the most common standard at 100.
The higher the number, the more quickly that food is converted . One of the highest numbers belongs to white bread, which has a glycemic index of 70. White bread can be converted to sugar very easily and quickly. Lima beans, on the other hand, have a glycemic index of 45, lentils 40, Peanuts 20.
Below is a link to a glycemic table for reference:
Glycemic Index Table
Generally, the more slowly a carbohydrates is converted to glucose, the better is for our health.
Other characters in the mix, the fiber, the fat or the proteins that in combination will slow the absorption of sugar into the system. Those are important variables.
For instance, although a rice cake has a high glycemic index, if you spread almond butter over it, the glycemic index drops dramatically. This may seem paradoxical, but adding the nut butter adds some protein, fat, and fiber to the carbohydrate of the rice cake. The addition of protein, fat, and fiber to a food slows down how quickly the body can convert the carbohydrate to glucose.
This is another reason why it is not healthy for people on a low fat and high carbohydrate diet.