PGX® has biologically important, dose-related effects on acute and delayed (second meal) postprandial glycaemia.
Viscous fibre in food has established health benefits but few functional fibre preparations are both effective and palatable. Our objective was to determine the most effective dose, formulation and timing of consumption of a novel fibre supplement (PGX) in reducing postprandial glycaemia.
Three trials were undertaken, each with 10 subjects (8M: 8F, age 24.4 ± 2.6 y). Granular supplement was tested at 4 doses (0, 2.5, 5.0 and 7.5 g) with breakfast (study 1). Granular and capsule forms of the supplement were given in a single dose (5 g for granules and 4.5 g in capsules) at -60, -45, -30, -15, 0 before and +15 min after a bread meal (study 2). Capsules at increasing doses (1.5, 3, 4.5 and 6 g) were consumed with the evening meal to determine effects on glucose tolerance at breakfast (study 3). Incremental area under the blood glucose curve was determined.
Granular PGX at breakfast time at doses of 2.5, 5 and 7.5 g reduced the iAUC by up to 50% in a linear dose-response fashion (p < 0.001). The granular form of PGX (5 g), but not the capsules, reduced glycaemia by up to 28% when consumed from -45 to +15 min (p < 0.001). Capsules containing 3, 4.5 and 6 g PGX consumed with the evening meal reduced glycaemia at breakfast by up to 28% (p < 0.001).