Fact Files :  The Glycaemic Index (GI)

The Glycaemic Index (GI) is a measure of how carbohydrate foods affect our blood glucose levels.
Some carbohydrate foods are broken down quickly while others are digested slowly.

A LOW GI carbohydrate breaks down slowly and produces a lower rise in blood glucose levels.
A HIGH GI carbohydrate digests more quickly and produces a fast rise in blood glucose levels.

Low GI food versus High GI food

Which Do I Choose?

Low GI carbohydrates are the best choice as they can help with:

1. Better blood glucose control
2. Improved insulin sensitivity
3. Weight loss
4. Feeling satisfied
5. Improving blood Triglyceride levels

Incorporating GI into your meals

• Try to include at least one low GI food at each meal and snack.
• Studies show that when a high GI food is combined with a low GI food, the complete meal results in having a moderate GI.

Other tips to consider.....

Food is not 'good' or 'bad' only on the basis of its GI.  You should also consider:

• Some low GI foods are high in fat - choose low-fat, low GI most of the time.
• The quantity or amount of carbohydrate you eat is also important for good blood glucose control.  As a general rule Low GI carbohydrates are most effective when distributed evenly throughout the day. This means avoiding large meals or skipping meals. 
• You cannot work out the GI of a food by looking at the back of the food label or comparing the amount of carbohydrates a food contains.  The GI of a food is affected a number of factors. These include:
• The amount and type of sugar in food
• The foods acidity
• The type of starch
• The foods fat and fibre content
• The protein content

The only way is to refer to a list of GI tested foods or look for this label.

For more information: www.glycemicindex.com
For further reading: The GI Factor – The glucose revolution by J. Brand Miller, K. Foster-Powell and S. Colagiuri.

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