In a clinically controlled setting, 50-gram portions of food are fed to people who have fasted overnight. The rise in blood sugar is measured every 15 minutes for 3 hours and then plotted on a graph. The area under the curve is measured and indexed against glucose at 100. That number is the food’s glycemic index. The higher the rise in blood sugar, the higher the glycemic index of that food.
Losing weight is not just a matter of reducing the amount of food you eat. Since foods with a low glycemic index are absorbed more slowly, the calories from the food you eat are more likely to be burned throughout the day as energy, rather than stored as fat. Low glycemic index foods help your body burn more body fat plus they have the added advantage of filling you up and keep you from getting hungry. Studies have shown that even when calorie intake is the same, you can lose more weight eating low GI foods vs. high GI foods.
Over the past 20 years 120 published research studies have been conducted on the value of a low GI-diet. There are two links that are particularly noteworthy: (a) www.mendosa.com/diabetes.htm and (b) www.glycemicindex.com.