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What is the glycaemic index and why is it so important?
What is the glycaemic index and why is it so important?
Nutrition
Diabetes
What is the glycaemic index and why is it so important?
What is the glycaemic index and why is it so important?

Not all foods have the same effect on blood sugar and insulin levels. Whether your blood sugar levels increase a lot or a little after a meal depends largely on the glycaemic index (GI) of the food you consume.

The GI is a measurement of the effect a food has on our blood sugar levels following consumption of carbohydrate containing foods. It shows how quickly and to what level a particular food can cause the blood sugar level to rise. The reference value for glucose is 100. The lower the GI, the slower and more gradual the rise in blood sugar levels. 

Meat, fish and low-fat dairy products are a good choice. Vegetables, pulses and wholegrain products also have a low GI thanks to the complex carbohydrates they contain. Complex carbohydrates are processed by the body more slowly and cause blood sugar to rise less rapidly than simple carbohydrates which pass quickly into the bloodstream. The GI of fruit varies greatly. For example, the GI of berries, apples and cherries is lower than watermelon or pineapple. Generally speaking, foods with a GI of less than 55 are better choices as these are deemed ‘low’. Foods with a GI of over 70 are categorised as ‘high’ and should be avoided as much as possible.

The GI is particularly important for people with Type 2 diabetes and those who wish to lose weight. The less our blood sugar level increases following a meal, the less insulin the body has to produce in order to regulate the increase. In this way, a lower GI supports stable blood sugar and insulin levels. Lower blood sugar and insulin levels also help the body to utilise fat for energy and increase the feeling of fullness, all of which makes losing weight easier. The effects of meals with differing GI’s can be clearly seen by checking your own blood sugar. If you measure your blood sugar 1 to 1.5 hours after eating food with a low GI, you will see a smaller increase than if you make a comparable measurement when you have eaten foods with a high GI

 

5. December 2017