04/04/2024
What is the Glycemic Index?
The Glycemic Index (or GI) looks at the effects of carbohydrate-containing foods on sugar levels in your bloodstream. Whenever you eat and digest carbohydrate-rich foods – foods like fruits, vegetables, grains and sweets – the end result is a rise in your blood sugar (your blood glucose). So, the GI is a measure of how high, and how quickly your blood sugar goes up when you eat a carbohydrate-containing food.
Generally, the highest GI foods are those that are low in fibre, but starchy or sugary – foods like white bread, sweet breakfast cereals, noodles, fruit juices and white rice. Since they are digested and absorbed relatively quickly, these high Glycemic Index foods tend to cause fairly rapid rises in blood sugar.
The lowest GI foods are those carbohydrate-rich foods that are whole and unprocessed. So, vegetables, whole fruits, beans, and most 100% whole grain foods – like brown rice, rolled oats, barley, quinoa and 100% whole grain bread – have relatively low Glycemic Index rankings. That’s because they’re high in fibre – which means they take longer to digest – and so your blood sugar rises more gently after you eat them.
Rather than a rapid rise in blood sugar, these wholesome foods lead to a slower release into your bloodstream, which provides you with more sustained energy. And, thanks to their high-fibre content, they may be more filling, too – so a diet that emphasises low GI foods can be a good strategy for weight control.