Effects of α-D-glucans with alternating 1,3/1,6 α-D-glucopyranosyl linkages on postprandial glycemic response in healthy subjects

Abstract

Slowly digestible carbohydrates have been demonstrated to be beneficial for the management of postprandial glycemic response both in individuals with diabetes mellitus as well as in the general population. The objective of this study was to evaluate the glycemic response and digestibility of a novel carbohydrate with 1,3 and 1,6 α-D-glucopyranosyl linkage pattern and with two different degrees of polymerization (DP). In a double blind, randomized, controlled, cross-over trial, participants consumed either an acute dose of 33 g of an a-D-glucan with average DP of 10 (alternan saccharide 10 [AS10]), an a-D-glucan with an average DP of 15 (alternan saccharide 15 [AS15]), or glucose syrup (as reference). The primary endpoint was the 3 h incremental area under the curve (3h-iAUC) for glycemic response, measured with a continuous glucose monitoring device. While AS10 resulted in a non-significant reduction in 3h-iAUC (-13%, p = 0.368), AS15 reduced 3h-iAUC by 33% compared to glucose syrup (p = 0.010). All test carbohydrates were fully digested, as demonstrated by breath hydrogen testing. These findings support the hypothesis that DP in combination with the glycosidic linkage pattern can affect glycemic response of carbohydrates. The significant reduction in glycemic response observed for AS15 is indicative of a slowly digestible carbohydrate that could be useful in glycemic management.