Sri Lankan Traditional Rice Varieties: Their Ability on Controlling Postprandial Glycaemic Response

Abstract

The current popularity of Sri Lankan traditional rice varieties stem from the many health benefits, specially the suitability for people with non communicable diseases (NCD) such as diabetes etc. Staples which produce lower glycaemic responses have been shown to be beneficial for people with NCD. However, scientific data on glycaemic response, glycaemic index (GI) of traditional rice is scarce and this study determined the glycaemic index and glycaemic load of traditional rice varieties Kaluheenati, Masuran, Gonabaru, Kahawanu, Kahamala and Hetadawee. Paddy was acquired from Rice Research Institute, Bathalegoda and authenticated traditional rice supplier and dehulled. Apparently healthy men and women with normal BMI (18.5-23), aged between 18-30 years (n=10) who volunteered were selected for the study and GI tested according to standard protocol. Values were presented as mean± standard error of the mean. Varieties Kaluheenati (60±5), Masuran (67±5), Gonabaru (63±7), Kahawanu (56±5) elicited medium GI while Kahamala (54±4) and Hetadawee (51±5) elicited low GI. Pericarp colour did not have an effect on GI as both red and white varieties elicited low or medium GI. Peak reductions against glucose for medium and low GI rice were 8.6% and 6.3% respectively. For each variety over 76% of volunteers exhibited either low or medium GI. Glycaemic load values for the given portion were high (26-33) but will be medium for an edible portion. The data scientifically confirms the suitability of consumption of these varieties for controlling the glycaemic response and related complications.