THESIS

cereals, and baked potatoes. Low glycemic foods include beans, peas oats, and some
types of rice and acidic fruits (Jenkin et al. 2002a).
6.2.1 Glycemic index definition and classification
The glycemic index (GI) is a numerical system of measuring how
much of a rise in circulating blood sugar a carbohydrate triggers the higher the
number, the greater the blood sugar response. So a low GI food will cause a small rise,
while a high GI food will trigger a dramatic spike. Food with GI of 70 or more
classified as high, a GI of 56 to 69 inclusive is medium, and a GI of 55 or less is low
(Foster et al. 2002). Before the development of the glycemic index beginning in 1981,
scientists assumed that our bodies’ absorbed and digested simple sugars quickly, with
producing rapid increases in our blood sugar level (Table 11) (Jenkins et al. 2002).
Table 11 Glycemic index and sweet taste value in various sugar
Sugar types Glycemic index
(Glucose = 100)
Glycemic index
(Bread = 100)
Sweet taste value (%)
(Sucrose = 1%)
Glucose 100 140 0.7
Sucrose 60 95 1
Lactose 46 65 0.4
Fructose 19 15 1.1
Source: Jenkins et al. (2002b)
6.2.2 Glycemic load definition
The glycemic load (GL) is a relatively new way to assess the impact
of carbohydrate consumption that takes the glycemic index into account, but gives a
fuller picture than does glycemic index alone. A GI value identify only how rapidly a
particular carbohydrate turns into sugar. It doesn't identify how much of that
carbohydrate is in a serving of a particular food. People need to know both things to
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