SINGAPORE - Each time Ms Juliana Lim goes grocery shopping, she lingers longer than most patrons along supermarket aisles. That is because she has to decipher the Glycemic Index (GI) of foodstuff from its fibre, sugar and fat content.
For the last two decades, the diabetic has been sticking to a low GI diet because spikes in her sugar levels will make her tired at work.
The GI is a measure of how quickly carbohydrate-containing food raises a person's blood glucose level.
"But choosing low GI food has not been easy as its information is not readily available on the Internet or food labels," said the 44-year-old executive.
It is why Temasek Polytechnic's Glycemic Index Research Unit and the Health Promotion Board (HPB) decided to create the first database on the GI of Asian food items, which will be available online next year.
The project, which has been two years in the making and is funded by the HPB, will cover everything from favourite Singaporean fare like chicken rice and char kway teow to household essentials, including bread.
The index will make it easier for the public to make healthier food choices and plan appropriate diets, said Ms Kalpana Bhaskaran, who heads the Temasek Polytechnic unit.
"Foods with high GI can lead to obesity, diabetes or other metabolic problems," added Ms Bhaskaran, who trained under Dr Thomas Wolever, the Canadian co- inventor of the GI concept.
The use of GI is better than simply counting calories, which does not gauge the quality of food, to track if one's diet is healthy.
Generally, the more processed a food item is, the higher its GI.
Food with low GI, such as wholegrain breads, is broken down more slowly during digestion and keeps a person feeling full longer. This helps cut down on snacking. Low GI food also prevents spikes in blood-sugar levels.
High GI food can increase blood sugar and insulin which, in the short term, can cause hunger pangs and lead to overeating. This increases the risk of weight gain, diabetes and heart disease in the long term.
High blood sugar levels can also cause complications such as heart and kidney diseases, especially in diabetics or those with weight issues.
Most food labels do not include the GI rating. Even the Internet does not have enough information, according to Ms Bhaskaran.
While Australia has been a pioneer in launching a GI symbol programme for food products in 2002, Singapore followed suit last year with its "Healthier Choice Label" programme, although this is for selected food items.
The HPB, meanwhile, told The Straits Times that it is working with food manufacturers to develop low GI food.
It is also engaging hawkers to use wholegrain noodles or rice in their dishes. For example, kway teow made from wholegrains has a lower GI level.
From next January, a cafe in Temasek Polytechnic will also start selling low GI dishes, such as carrot cake made with wholegrain flour, that come from recipes brainstormed by students.
Said Ms Bhaskaran: "It is important to inculcate such awareness from a young age so that the next generation will adopt healthier diets."
WHAT IS THE GLYCEMIC INDEX?
The Glycemic Index, or GI, is a scale which measures how much a food containing carbohydrates raises blood glucose levels.
Foods with a higher GI, such as white bread, can cause rapid spikes in blood sugar levels. Those with a lower GI, such as whole oats, are digested more slowly, causing more gradual and smaller changes in blood sugar levels.
GI is computed on a scale of zero to 100. Foods with low GI register a value of 55 and below, medium GI ranges from 56 to 69 and high GI means 70 and above.
Low GI foods include dried beans and legumes such as kidney beans and lentils, green leafy vegetables, most fruit, and many wholegrain breads and cereals.
Fat and fibre tend to lower the GI of a food and generally, the more cooked or processed a food, the higher its GI.
Knowing the GI values of food can help with better planning for a healthy diet. Research has shown that a low GI diet can help prevent heart disease and diabetes, control cholesterol levels and maintain a healthy weight.
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