The effect of low and high glycemic index based rice varieties in test meals on postprandial blood glucose, insulin and incretin hormones response in prediabetic subjects

Abstract

© All Rights Reserved. Evidences have shown that low glycemic index (LGI) and glycemic load (LGL) of rice exert significant benefits to the population who are at risk to type 2 diabetes. LGI rice could minimize the fluctuation of blood glucose and insulin level. This study was aimed to determine the GI values of four new breeding rice varieties developed by using pseudo-backcrossing techniques. Furthermore, the comparison of GI values with that of commercial varieties (Jasmine and Basmati rice) was also described. Twenty two healthy subjects were fed with a reference food and cooked rice varieties containing 50 g available carbohydrate. All the new breeding rice varieties had GI values ranged between 48.1%-66.1%. Moreover, the effect of low GI (PK+4#20A09) and high GI (Jasmine rice) rice in test meals were studied in 12 prediabetic subjects to determine the changes of postprandial blood glucose, insulin, glucagon-like peptide-1 (GLP-1) and glucagon-dependent insulinotropic polypeptide (GIP). Results showed that LGI-LGL test meal (GI=41.7%, GL=21.3) could significantly lower blood glucose (P < 0.05) at time point 30, 45, 60 and 90 minute and insulin concentration (P < 0.05) at time point 60 minute when compared to that of HGI-LGL (GI=70.3%, GL=35.8). There was increase of GLP-1 level in subjects fed with LGI-LGL test meal whereas the mean GIP was significantly (P < 0.05) decreased at time point 30 and 60 minutes. Our result suggested that new breeding rice, PK+4#20A09, could have beneficial effect on lowering the glycemic response in prediabetic subjects.