Glycemic Index (G.I.)

Have you heard the word Glycemic Index? Or your doctor talked to you about G.I? G.I. stands for Glycemic Index. What is Glycemic Index? In the dear Doctor section of Health and Home March-April 2011 issue, the Glycemic Index (G.I.) is a measure of the effects of carbohydrate foods on blood sugar levels after is absorbed from the digestive system. After ingestion of carbohydrate foods, they break down quickly during digestion to produce glucose that is delivered into the bloodstream. Carbohydrate foods that are rapidly absorbed as sugar is considered to have a high GI, while carbohydrate foods that break down more slowly, releasing glucose more gradually into the bloodstream, have a low GI. The concept was developed by Dr. David J. Jenkins and colleagues at around 1980 at the University of Toronto in their research for foods that are best for people with diabetes.

Glycemic index is reported as a number from 1-100 which was computed by the comparison of the level of blood sugar that a specific food exerts to the level exerted by 50 gms of sugar when taken in (considered as 100). After taking the average level from several “normal” subjects, the GI is reported in numbers. A low GI is a level 55 or below. Medium GI is 56-69 level, and a high GI is 70 and above.

A lower GI suggests slower rates of digestion and absorption of the foods’ carbohydrates. This may also indicate greater extraction from the liver and periphery of the products of carbohydrate digestion so that glucose does not stay in the bloodstream for a longer time. Foods that have low GIs are ideal for people who are ever weight and do not want to develop diabetes.

The table below is the sample list of GI levels of common carbohydrate foods.

Classification	GI range	Examples
Low GI	55 or less	Most fruits and vegetables, legumes, whole grains, meat, eggs, milk, nuts, fructose, and products low in carbohydrates
Medium GI	56-69	Whole wheat products, brown rice, sweet potatoes, sucrose, ice cream
High GI	70 and above	Baked potatoes, watermelon, white bread, most white rice, corn flakes, extruded breakfast cereals, glucose