UNDERSTANDING GI

When a person is diagnosed with diabetes or pre-diabetes, eating can suddenly become such an overwhelming activity. Not only do you need to understand the complicated concepts of insulin and blood glucose, but also consider the carbohydrate content and Glycaemic Index (GI) of foods.

 

Have you ever felt like you’re riding a GI roller coaster? Here are some tips to help you understand GI.

 

WHAT IS GI?

GI stands for Glycemic Index. It ranks carbohydrate food according to how quickly they raise the sugars in our blood. Basically, the higher the GI, the quicker the rise in blood sugar levels.

 

HOW DOES GI AFFECT SUGAR LEVELS IN OUR BODY?

Let’s start with the basic digestion process of carbohydrates. When we eat carbohydrates (either sugars or starches), they are broken down into a simple sugar called glucose. Our muscles, brain, and nervous system all use glucose as fuel.

 

Carbohydrate foods with a high GI will be broken down and absorbed very quickly – this triggers a rapid rise in blood glucose levels. On the other hand, foods with a low GI will be slowly broken down and absorbed, causing a slower and more sustained release of glucose into the bloodstream (which is what we want!).

 

HOW TO DETERMINE HIGH AND LOW GI?

Unfortunately, you can’t tell if a food is low or high GI by looking at it, but there are a few good tips we can use to try and make low GI choices.

  • Simple sugars (such as honey, sugar and syrup) have a high GI.
  • Processed and cooked foods are easier for our body to digest. The more processed or cooked a food is, the quicker it will be digested and absorbed by our bodies leading to those rapid spikes in blood sugar levels. For example, juice has higher GI than whole fruit and soft cooked pasta has higher GI than al dente pasta.
  • Most fruits tend to have a low GI but generally speaking, the riper the fruit, the higher the GI.
  • Fibre tends to lower the GI of foods. For example, grainy bread has a lower GI than white bread.

 

THE LOW GI SYMBOL

Nowadays, the food industry makes it easier for us to find low GI options. Foods that carry the ‘Low GI’ symbol mean they have been tested in a laboratory and meet strict nutrient criteria. The symbol can be used as a quick and reliable tool to help us make positive food choices. So, look for the Low GI symbol on the supermarket shelves!

 

Article co-authored  by Nyssa Djualim who is currently studying a Masters in Nutrition and Dietetics at the University of Sydney.