Carbohydrates are the main source of energy for your body. It’s not just how much carbohydrate we consume that’s important for a healthy diet, it’s the type that’s the key.The Glycaemic Index (GI) is a guide to help you eat the right type of carbohydrate and make nutritious food choices.
GI is a rating from 0 to 100 calculated according to how quickly different carbohydrates are digested and raise the blood sugar level.
Low GI foods like oat cakes, wholegrain bread and strawberries that are digested more slowly, help keep your blood sugar and your energy levels even.They also help you feel fuller for longer so you don't feel hungry again so soon.
High GI foods, like white bread, cornflakes and rice-cakes, are digested quickly, giving a short-term boost to your blood sugar level, and a blood sugar low a few hours later, leaving you feeling hungry and exhausted.

What’s more, low GL foods also stabilise appetite. So if you eat a diet containing low GL foods such as oat cakes, you not only help your waistline, but you don’t want to eat too much.

What is Glycaemic Load?

While GI tells you whether the carbohydrate or type of sugar in a food is ‘fast-releasing’ it doesn’t tell you how much there is in the food. So, you could have a food with a high GI, such as watermelon, but very little actual carbohydrate in it. Or a food with a medium GI, such as chocolate, that’s loaded with sugar.

Glycaemic Load, or GL, is a measure of the quantity of carbohydrate in a typical serving, multiplied by the quality (the GI).The GL of a food tells you exactly what it’s going to do to your blood sugar level, your energy and your weight. It’s therefore a much more reliable measure of whether the food will keep you healthy