Keeping You Full
Begun as a diet to help people control their diabetes, the general rule of the GI diet is: the higher the glycemic index, the faster a food is metabolized by the body. If a food is digested and broken down by the body quickly, your blood glucose (commonly referred to as blood sugar) levels rise rapidly, leading to a quick insulin response, making you feel tired and hungry sooner. Foods with low GI are metabolized slower, meaning they sit in your digestive track longer and are gradually absorbed by the body. This leads to a more gradual blood glucose increase, keeping your hunger satiated longer.
While a few studies have shown that following a low GI diet will keep you feeling fuller longer, helping you lose weight, there is no conclusive understanding of how this diet works. Keeping track of the GI of foods can get tricky, but this early evidence suggests that it may prove to be a useful tool for dietary planning.
GI assigns a value to a food based on the average body's metabolism of a simple carbohydrate: usually table sugar or white bread, assigned a value of 100. All other foods are then ranked according to how 50 grams of it, as compared to how 50 grams of sugar or white bread, affects one's blood glucose levels after a period of time. A value below 55 would be considered a low GI; a value from 56 to 69 would be a moderate range; anything above 70 is considered to have a high glycemic index. While such values provide a handy guide, they have not been standardized, so two different charts may show a different GI value for the same food.
Related to GI, glycemic load is a measurement that not only takes into account the glycemic index of a food, but also how much of it is there. Since, no matter what, you still can't eat heaping portions of any kind of food, glycemic load may be a better dietary tool than GI alone. Glycemic load can be assigned to an entire meal or to the food eaten over an entire day, for example.
