What is meant by glycemic index?

The glycemic index is a scale that ranks a carbohydrate-containing food or drink by how much it raises blood sugar levels after it is eaten or drank. Foods with a high glycemic index increase blood sugar higher and faster than foods with a low glycemic index.

Actual (sugar) has a glycemic index of 100 and other foods measured are ranked as low, moderate and high GI foods.

There are three GI categories:
*Low GI (55 or less) Choose Most Often
*Moderate GI (56 to 69) Choose Less Often
*High GI (70 or more) Choose Least Often

Foods in the high GI category can be swapped with foods in the medium and/or low GI category to lower GI. In term of long-term health, Low GI Diets are important in reducing the risk factors of developing Type 2 diabetes, heart disease and other degenerative diseases.

White rice has a glycemic index value of 73, while foods such as noodles and pastas usually fall at a moderate value on the glycemic index.

Different types of noodles have different glycemic index scores, with egg noodles at 40, spaghetti boiled for 10 to 15 minutes at 44 and whole-wheat spaghetti at 37. Boiling noodles for longer times will increase the glycemic index score, and leaving them al dente will decrease the score slightly.
What is meant by glycemic index?