What is the Glycaemic Index?
The Glycaemic Index (GI) is a system that ranks carbohydrate containing foods from 1-100, according to the rate at which they are broken down and absorbed into the bloodstream.
Foods that are broken down slowly are considered to be low GI and have a ranking between 0-55. Low GI foods produce relatively small fluctuations in blood glucose levels.
Foods that are broken down and absorbed into the blood quickly are high GI and are ranked between 70-100. High GI foods will cause a rapid rise in blood glucose levels.
Moderate GI foods have an index of between 56 and 69.
- Low 0-55
- Moderate 55-69
- High 70-100
The role of carbohydrates and GI
Carbohydrates are an essential part of the diet, as they are one of the body’s major sources of energy.Carbohydrates are found in a variety of foods,including breads, pasta, rice, breakfast cereals, potato and corn. The sugars found naturally in fruit and diary products, as well as the sugar contained in biscuits and lollies, are also carbohydrates.
When we eat carbohydrate-rich foods, our digestive system breaks them down into glucose (a simple sugar), which is absorbed into the blood stream. In this way, glucose is transported to our muscles and other cells to be used as energy with any excess glucose being stored in the body.
Why choose low GI foods
Including low GI foods in a healthy, well-balanced diet can provide several health benefits. A low GI diet can:
- Help you feel fuller for longer by reducing your appetite between meals.
- Assist with weight management and sustainable weight loss.
- Reduce the risk of developing Type II diabetes and heart disease.
A healthy balanced diet means enjoying a wide variety of foods and making sure you eat plenty of fibre-rich breads and cereals, fruit and vegetables, as well as lean meat, fish, poultry, legumes and low fat dairy products.
GI and sport
Whether you’re an athlete or exercising for enjoyment, you need enough carbohydrate to fuel your muscles and brain during your training. Low GI foods, eaten two hours before exercise provide a slow-release source of glucose into the blood, which can assist with endurance performance.
High GI foods eaten during exercise can help maintain blood glucose levels by providing extra energy and also helping replenish your energy stores if eaten after you finish training.
Making the switch from high to low GI foods
Try to include some low GI food at each of your meals. Studies suggest that combining low GI foods and high GI foods in the one meal can reduce the overall GI of the meal. The GI of some common foods are listed below:
Low GI food examples (0 - 55):
- Fresh apple
- Soy beans
- Fresh orange
- Multigrain instant porridge
- Sweet potato
- Processed bran cereal
- Meat, chicken and fish
- Nuts and seeds
- Many low-fat dairy products
- Some breakfast cereals like Kellogg's Special K Original
- Mixed wholegrain breads
Moderate GI food examples (55-69):
- Basmati and Arborio rice
- Wild rice
- Sultanas and raisins
- Some breakfast cereals like Kellogg's Sultana Bran Buds
- Fresh apricots
- Kiwi fruit
- Fresh pineapple
- Table sugar
- White pita bread
High GI food examples (70-100):
- Jasmine, brown, Calrose rice
- Fresh watermelon
- Fresh rockmelon
- Dried dates
- White bread
- Plain waffles
- Puffed wheat cereal
- Plain popcorn
- Instant porridge
- Puffed rice cereal
Low GI meal ideas for breakfast
Try some low GI breakfast cereals or mueslis. Cereals provide an important source of fibre, B vitamins and iron. Adding some low fat yoghurt or milk will help boost your calcium intake. Top it off with some mixed berries or a banana to add extra flavour and variety.
Low GI meal ideas for lunch
Seeded or multigrain breads are a great alternative to white bread. Add some tuna or salmon and your favourite salad vegetables. Alternatively, try a Nicoise Salad and replace some of the potatoes with kidney (or other) beans to lower the GI of the meal.
Low GI meal ideas for dinner
How about spaghetti bolognaise made from wholemeal pasta with a side salad or baked sweet potato and vegetables served with a piece of lean grilled steak or fish. For a quick meal, why not try a chicken stir-fry sprinkled with some cashews or peanuts and a side of basmati rice.
Low GI snack ideas
Throw some mixed berries into a tub of low-fat yoghurt or mix in some raw nuts and seeds for a different texture. Add some low GI fruits to a low-fat custard. Grab a couple of whole wheat crackers and spread with some natural (low salt) peanut butter or low fat cheese spread. For a snack on the go, pick up a small nut bar or fruit & nut trail mix.
Read more about kids' nutrition
- The a-z of vitamins and minerals
- Learn about the glycaemic Index
- Healthy food pyramid
- Iron and kids
- Calcium and kids
- Exercise for kids health
- Health and fitness for kids
- Nutrition information panels
- Eating for peak school performance
- Picky eaters
- How much fibre does my child need?
- Why fibre is fabulous
- All about fibre
This article was supplied by the team of Nutritionists at Kellogg's for Kidspot, New Zealand's leading education resource for parents.