Abstract

The glycemic index (GI) is an important parameter of food quality which compares the hyperglycemic effect of a tested meal with pure glucose. For most foods in the Middle East, the glycemic index has not been defined yet. The aim of this study is to determine the GI of Iranian rice and to evaluate the type of cooking method on GI value. To determine the GI, measured portions of food containing 50 g of carbohydrates were eaten by 10 healthy volunteers (5 men and 5 women) after an overnight fast. Capillary blood samples were taken at 0 (fasting), 30, 60, 90 and 120 min after the meal. Blood glucose curves were constructed from blood glucose values. The GI was calculated by dividing the incremental area under the curve for the tested food (fluffy rice and steamed rice) by that for the standard food (same amount of glucose) and multiplying by 100. In each volunteer, each food was tested thrice so that 3 GIs were obtained and the average was calculated. The GI for tested food was calculated as the mean from the respective average GIs of the 10 volunteers. The GI values of fluffy rice and steam rice were 55.38±17.16 and 66.25±18.49 respectively. Statistically significant difference was not observed. These results indicate that Iranian rice should be classified as medium GI food.

Key words: Rice, glycemic index, glucose, Middle East, human subject.

Abbreviation

GI, Glycemic index; CHD, coronary heart disease; FAO, Food and Agriculture Organization of the United Nations; IAUC, incremental area under the curve; WHO, World Health Organization.