What is the glycaemic index?

The Glycaemic Index (GI) is a classification of carbohydrate-containing foods based on their potential effect on blood glucose levels. Foods are given a GI number according to their potential effect on blood glucose levels. Glucose has a GI of 100 and other foods are measured against it. In general slowly absorbed foods have a low GI rating, while foods that are more quickly absorbed have a higher rating.

When you have diabetes, choosing slowly absorbed carbohydrates, instead of quickly absorbed carbohydrates, may help even out your blood glucose levels, help fill you up and feel less hungry between meals.

Other things can affect the GI of a food such as how ripe it is, how processed it is and how it is cooked. Fat and protein lower the GI of a food.

It is important not to just concentrate on the GI value of foods, portion sizes of any carbohydrates are important. Low GI foods should not be eaten without restriction nor should high GI always be avoided. Try to think about the balance of your meals, which should be low in fat, salt and sugar and contain fruit and vegetables. We eat different foods in different amounts so portion size will also affect your glucose levels.

GI is just one tool or approach to help you become more aware of the carbohydrates you eat. If you are keen to know more, there are lots of books on the GI. You could ask you diabetes nurse or doctor to refer you to a dietician for further support.