Substituting peas for rice significantly reduces postprandial blood glucose response and glycemic index

: Diabetes is one of the most common chronic diseases affecting Canadians and lifestyle modifications that include a diet high in fibre may lower the risk of developing type 2 diabetes. Peas are high in fibre and protein, and replacing a portion of a high starch food like rice with peas may limit the rise in blood sugar after a meal. The objective of this study was to compare the post-prandial glucose response following consumption of white rice with and without 3 common market classes of peas. Twenty-four healthy adults (9 men/15 women, age 26 ± 4.7; BMI 23.7 ± 4.0 kg/m2, % body fat (men) 19.2 ± 11.9, % body fat (women) 27.5 ± 9.7) completed the randomized controlled crossover clinical trial at the I.H. Asper Research Institute in Winnipeg, MB. Each participant attended six 2.5-hour study visits separated by washout periods of 3-15 days. At the first and sixth visits, participants received 50g available carbohydrate (AC) from white bread. At visits 2-5, participants received in random order 50 g AC from rice or 20 g AC from rice + 30 g AC from peas (yellow whole, yellow split, green split). Fasting and 15, 30, 45, 60, 90 and 120 minute post-prandial capillary blood samples were collected for analysis of blood glucose and plasma insulin. Repeated measures ANOVA and differences in LSMeans were used to determine statistical differences in incremental area under the curve (iAUC) for glucose and insulin, as well as Glycemic Index (GI) among treatments. Compared to white rice alone, glucose iAUC was significantly decreased (p<0.0001) by 29-31% when peas were combined with rice. There was no difference in insulin iAUC when peas were combined with rice compared to rice alone. The GI of rice (99.5±7.4) was significantly decreased (p<0.01) by addition of each pea: (yellow whole (76.6±7.4), yellow split (67.6±7.4) and green split (69.2±7.4). These results show that replacing 60% of the AC from white rice (a high-GI, starch-rich food) with peas supports a Function health claim related to the reduction in post-prandial glycaemic response. (Funded by AAFC Growing Forward 2 and Pulse Canada Cluster).