The Glycaemic Index (GI) is a method of rating carbohydrate in foods (between 0 and 100) based on their effects on blood glucose (sugar) levels. Foods with a high GI contain carbohydrates that are digested and absorbed quickly and cause a rapid rise in blood glucose levels.
Foods with a low GI contain carbohydrates that are digested and absorbed more slowly thereby having a lesser impact on blood glucose levels.
GI AND Health
Research suggests that including low GI foods as part of a healthy eating plan may be beneficial if any or all of the following apply:
- You have diabetes, or are at risk of developing diabetes;
- You have raised blood cholesterol levels, poor insulin response and are at risk of heart disease;
- You want to control your body weight.
GI may also be useful if you are an athlete as it is thought that eating low GI foods prior to endurance events may enhance your exercise capacity. Studies have also shown that rapid replenishment of your muscle fuel stores after exercise can be achieved by eating high GI foods during the first 24 hours of recovery after events.
What Can You Do?
Eat Low GI Foods: try to include low GI meals and snacks where possible. The following table lists a range of low, moderate and high GI foods.
The Glycaemic Index of Common Foods*:
Low GI Foods (55 or less)
• Apples, bananas, pears, oranges
• cherries, peaches
• Dried apricots, dried apples
• Barley, semolina
• Mixed grain bread, fruit loaf
• Porridge, All Bran, toasted muesli
• Pasta e.g. spaghetti, macaroni, noodles
• Lentils & most legumes
• e.g. baked beans, chickpeas
• Sweet potato, peas, carrots, taro
• Milk, Sanitarium So Good® soymilk
• Low-fat yoghurt, custard
Moderate GI Foods (56-69)
• Apricot, pineapple, rockmelon
• Raisins, sultanas
• Basmati & Doongara rice
• Rye bread, crumpets
• Weet-Bix®, natural muesli
• Gnocchi, couscous
• New, boiled or canned potato
• Sweetened condensed milk
• Yoghurt drink, Vitari
High GI Foods (70 or more)
• Dried dates
• Calrose white rice, brown rice
• White bread, English muffins
• Puffed wheat, cornflakes, rice bubbles
• Rice pasta
• Broad beans
• Baked, pale skin potato, pumpkin
*Brand Miller J, Foster-Powell K, Colagiuri S, Leeds A.The G.I. Factor, 2nd edn. Netley: Hodder & Stoughton, 1998.
GI Tips to Remember:
- Meals that are made up of several different foods will have an overall GI that is a combination of the GI contributed by each food. So, by adding a low GI food to a meal, the overall GI of the meal can be lowered.
- There is room for high and moderate GI foods in a balanced diet – many of these foods can provide important sources of nutrients. It is important to include a wide range of foods in your diet every day for good health.
- Many more foods (other than those listed in the above table) have been tested for GI. The best way to check the GI of the carbohydrate foods you are buying is to contact the manufacturer or look on the label to see whether it has been tested. You could also check out the website www.glycemicindex.com.
- It is important to remember when making your food choices that GI should not be used in isolation to other nutrition principles. You should also check the nutrition contents of products and be sure to choose items that are low in fat, especially saturated fat, salt and sugar (where possible), provide fibre and include a wide variety of foods in your diet every day.