Glycaemic Index of Foods

The glycaemic index (GI) is the ranking of foods according to the effect that a given amount of carbohydrate has on blood sugar levels.

The ranking given to a particular food indicates the rate of digestion and absorption of a carbohydrate-rich food or beverage.

To determine the glycaemic index of a food, blood sugar levels are monitored for two hours following consumption of a volume containing 50g of carbohydrate.

Foods are given a ranking of between 0-100 according to the specific blood glucose response. Foods are ranked in comparison to the effect on blood sugar levels following consumption of glucose or white bread, which are given a GI of 100.

The foods we eat have a significant impact on our blood sugar levels. Control of blood sugars within a fairly narrow range is essential for good health and energy levels. Glucose in the blood is the fuel for our brain and muscles. If our blood sugar levels get too low (hypoglycaemia) we do not get the fuel we need and this can make us feel tired, dizzy and generally unwell.

Factors that help to improve blood sugar control include:
Maintaining a healthy body weight and body fat levels
Adequate carbohydrate intake spaced throughout the day
Slow release of carbohydrate into the bloodstream

Incorporating more low glycaemic index foods into the daily food intake helps to slow the release of carbohydrate into the bloodstream and help control blood sugar levels.

Conversely, high GI foods are quickly digested and absorbed, causing a sharp rise in blood sugar levels, followed shortly by a significant drop in blood sugar. Hypoglycaemia and the associated negative symptoms are then experienced.

New food labelling laws will soon require that the GI be measured and stated on food labels.

A number of publications are available that contain more information on GI and lists of different foods and their GI values.

Try to include at least one low GI food at each meal.
Choose low GI foods as snacks.

Aim for 50% of the total carbohydrate foods that you consume as low GI

Pasta Mahatma Premium Classic Rice Instant noodles
Rolled oats/porridge Rice bran
Bran cereal
Bread, Dark rye/Ploughmans/heavy mixed grain
Heavy fruit loaf Milk, low fat
Yoghurt, low fat
Ice-cream, low fat
Apple Banana, firm
Pear
Orange
Plum
Grapes
Citrus/stone fruits
Dried apricots
Carrots
Sweet corn
Sweet potato
Legumes - kidney beans, lentils, chick peas, baked beans
Peas

Moderate GI

Muesli flake cereal
Muffins (cake-style)
Plain sweet biscuits
Soft drink
Raisins
Ice-cream
Sucrose

High GI

Bread, white and wholemeal
Bagels
Rice crackers
White rice
Cornflakes
Weetbix
Cocopops
Plain crackers / puffed crispbread
Corn chips
Watermelon
Honey
Glucose
Jelly beans
Potato

Performax (Country Life)
Ploughman's Whole-Grain (Quality Bakers)
Multi-grain 9-grain (Tip Top)
Holsom's Wholemeal with Wheatgerm (Tip Top)
Burgen Mixed Grain (Tip Top)
Burgen Oat Bran and Honey Loaf with Barley (Tip Top)
Burgen Soy and Linseed (Tip Top)
Sourdough rye
Heavy fruit bread/Raisin bread

Dry biscuits and crackers are generally high glycaemic index

Breakfast Cereals

Processed bran cereals eg. All-Bran Rolled oats/Porridge
Muesli
Special K
Guardian

Cereal Grains

Pasta
Instant noodles
Hokkien noodles
Bulgur (cracked wheat)
Barley, pearled
Mahatma Premium Rice (most rice is high GI, Basmati rice moderate GI)

Fruits

Most fruits have low glycaemic index.

Tinned apricots, overripe bananas, paw paw, pineapple, rockmelon, dried fruits (except dried apricots/apples) have moderate glycaemic index.

Watermelon, lychees and dates have a high glycaemic index.

Vegetables

Most vegetables have low glycaemic index.

Potato and pumpkin high glycaemic index, tinned beetroot have a moderate glycaemic index