Mixed grain containing giant embryonic brown rice improves postprandial glycaemic response in healthy subjects

Aim Mixed grain, which contributes to lowered glycaemic responses, has been shown to be effective in dietary management of patients with impaired glucose tolerance or diabetes. Methods The present study determined the postprandial blood glucose response of 20 healthy volunteers to mixed grains containing giant embryonic rice (MG‐GER) or giant embryonic brown rice (MG‐GEBR) compared with white rice (WR) in a randomised crossover design. Plasma glucose and serum insulin at 0, 15, 30, 45, 60, 90, 120, 150 and 180 minutes were measured, and glycaemic index (GI) and incremental area under the curve (iAUC) were calculated. Results The GIs for WR, MG‐GER and MG‐GEBR were 86.75 ± 5.78, 76.09 ± 7.01 and 69.33 ± 6.54, respectively. The 120‐minute iAUCs after administration of MG‐GER or MG‐GEBR were significantly lower than that of WR. In addition, the MG‐GEBR diet group had a significantly lower C‐peptide concentration at the 120‐minute time point when compared to the WR group. Conclusions These results suggest that consumption of MG‐GER or MG‐GEBR instead of WR is more effective to reduce postprandial glucose levels without increasing insulin secretion.