The glycemic index, or GI, measures how a carbohydrate-containing food raises blood glucose. Foods are ranked based on how they compare to a reference food — either glucose or white bread. Glycemic Index uses a scale of 0 to 100, with higher values given to foods that cause the most rapid rise in blood sugar.
The diet, which was originally designed for diabetics and is often prescribed to cardiac patients, is based on established scientific fact that different carbohydrates raise blood sugar levels faster than others. By keeping insulin levels stable by eating foods with a low GI, this keeps hunger at bay and helps to prevent fat formation and also encourages fat to be converted back into energy.
High-GI foods are quickly digested and absorbed within the body. This causes your blood sugar to become a roller coaster as it fluctuates regularly, ultimately leaving you with a sugar high followed by a sugar crash. High-GI foods often include mainly your simple or "bad" carbs that are low in fiber and other nutrients.
Low-GI foods are digested at a slower rate which helps keep your blood sugar levels more stabilized and controlled. This leaves you feeling more energetic and more satiated. Low-GI foods are more of your complex carbs or "good carbs" that are higher in fiber and nutrients. They help keep you feeling full for a longer period of time, but with fewer calories.
For a healthy diet, most physicians recommend eating from the low-moderate GI foods list and eating sparingly from the High-GI foods list. By choosing the right carbs, you will be able to lose weight if needed as well as feeling your best.
Sounds simple enough? The GI Diet works because we are taught to eat the correct carbs. Fat is not the main enemy-selecting the innapropriate carbs can do more damage as it sits and converts to simple sugars.
Below, is a sample of popular foods and their GI ratings.
Snacks & Sweet Foods
Chart courtesy of: http://www.the-gi-diet.org/lowgifoods/