The Glycaemic Index (GI) is a measure of how quickly foods containing carbohydrate make your blood glucose levels rise after eating them.
Foods containing Carbohydrate include bread, pasta, maizemeal, potatoes, sweet potatoes, noodles, rice and cereals, Fruit and fruit juice, some dairy products such as milk and yoghurts, Sugar and other sweet foods, Non-diet soft drinks, Pies, pastries, biscuits and cakes, vegetables.
Foods are ranked as high GI and low GI. High GI foods are quickly digested and cause quick and sharp rises in the blood glucose levels. Low GI foods will make your blood glucose rise more slowly. It is important to choose more of low GI foods than high GI foods or combine high GI foods with low GI foods in a meal.
Foods with a high GI are not necessarily bad foods. For example potato crisps have a medium GI but a baked potato has a high GI. Despite this, a baked potato is better for your health than potato crisps, which are higher in fat and salt. And all lower GI foods are not necessarily healthy – chocolate and ice cream have a low to medium GI rating. So, the key is to use GI in the context of balanced eating.
The GI principle cannot be used alone as it does not take into account factors such as saturated fat and trans fatty acids. It is therefore important to consult a Registered Dietitian for more information on blood glucose control.