Only a small number of people actually know what GI stands for, most people have only heard of low GI but are still not sure what that actually means. This article is here to make you a GI expert! GI stands for glycaemic index which is a measure of how quickly a carbohydrate food is broken down by your body & released into your blood… AND no, not all carbohydrates are broken down at the same rate! Now this measure is a scale & every carbohydrate food has been measured in a lab & given a numerical value, however, these are then assorted into a low & high category to make it easier for people to understand.
The Physiology of Carbohydrate Absorption:
To understand the importance of GI, let’s first look at the physiology. The breakdown of carbohydrate starts as early as mouth, where your teeth & saliva begin to break it down. From there the stomach breaks it down further & almost blends it into a puree/liquid consistency. Once at this consistency, the carbohydrate will move to the intestines where further break down & then the absorption of the carbohydrate into the blood occurs, usually with assistance of enzymes. All carbohydrates need to be broken down into the simple form of sugar before it can be absorbed into the blood.
This helps us understand why some carbohydrates are absorbed quicker than others. The closer the carbohydrate already is to that simple form of sugar; the less breakdown time is required & the quicker it reaches the absorption stage.
So… What Does High GI Mean?
High GI foods are foods that are broken down & absorbed quicker — this means your blood sugar levels will soar high more quickly, or as some would describe it, gives you that sugar high. The other aspect of high GI foods is that they are in your digestive system for less time which means you are going to be hungry again more quickly & end up eating more food & calories by the end of the day.
So how do we spot these foods?
These foods are going to be higher in sugar & generally lower in fibre. Therefore, when you look on your food labels; look at your total carbohydrate section & compare this value to the sugars (located as a subgroup on the panel under carbohydrates) — the closer the sugars value is to the total carbohydrate value, the more quickly it will be digested.
You can also look at the ingredient list & if sugar is in the top 3 ingredients; it is likely to be high in sugar. But watch out, there are other names for sugar on labels including: corn syrup, fructose syrup, honey, golden syrup, maple syrup.
Products like lollies, chips, chocolates, juice, flavoured milk, cakes, biscuits & soft drink are quite obviously going to fall into this category. But even some breads, rice & pastas can be classified as high GI & these are often harder to identify — keep reading to find out some tricks to help you with this.
So… What Does Low GI Mean?
Low GI carbohydrates take longer to be broken down & digested which means blood sugar levels very gradually increase over a longer period of time & they do not reach as high as when high GI foods are eaten. They also help to keep you feeling fuller for longer, which makes it easier to eat less over the day.
So how do we spot these foods?
They often are fresh foods with the least amount of processing like fruits, potatoes, whole grain crackers & unsweetened dairy foods. When reading food labels, they are the foods with the much higher value next to the total carbohydrate compared to the sugars value & will have a higher dietary fibre value. Surprisingly, not all brown bread/rice/pastas are actually low GI due to different company’s methods of processing the foods. Some easy go-to tricks to help identify these foods include:
· You can ask your baker for a low GI bread — they should be able to direct you
· Choose long grain rice over short grain rice including basmati & doongara
· Choose more fresh foods with less processing — they often don’t have packaging such as: potatoes, sweet potatoes & fruits
· Don’t add sugar when you are cooking or on top of your cereals
· Less sweet cereals, mainly brans/whole grain cereals or oats
· Wholegrain crackers — these are not sweet, including: Vita-Weats & RyVitas
· Unsweetened dairy foods like plain yoghurt or milk
· Look for labels on packets indicating Low GI — many companies will post it on their package if they are low GI
· Look for the ‘Glycemic Index Foundation’ symbol on products — this means the product is certified as low GI
· You can also visit the ‘Glycemic Index Foundation’ website to learn more or to look up specific food types, they keep a list of low GI foods grouped by food types https://www.gisymbol.com
Overall, to improve your health, try to aim for a low GI carbohydrate food at each meal & snack in your every day routine & save the high GI foods for the occasional treat.
