Reduction of Postprandial Glycemia by the Novel Viscous Polysaccharide PGX, in a Dose-Dependent Manner, Independent of Food Form

OBJECTIVE: Health benefits of viscous fiber intake are well established; nevertheless few effective and palatable preparations are available. The objective of the study therefore was to determine palatability and effectiveness of escalating doses of PGX, a novel viscous polysaccharide (NVP), in reducing postprandial glycemia when added to a liquid and a solid meal. DESIGN: Two open-label, randomized, controlled trials were undertaken. SETTING: Glycemic Index Laboratories, Inc, Toronto, Ontario, Canada. SUBJECTS: Two groups of 10 healthy subjects each (group 1: 5 M, 5 F; 35.6 ± 13.2 y; 24.6 ± 2.1 kg/m²; and group 2: 3 M, 7 F; 33.5 ± 11.1 y; 26.3 ± 5.2 kg/m²) were studied. INTERVENTIONS: Zero, 2.5, 5, and 7.5 g of NVP were added to a glucose drink (group 1) or to white bread and margarine (WB + Marg) (group 2). Subjects repeated glucose control (group 1) or WB control (group 2) 3 times to allow calculation of the glycemic index (GI). MEASURES OF OUTCOMES: Palatability of foods and capillary blood glucose concentrations were measured fasting and at 15, 30, 45, 60, 90, and 120 minutes after the start of the meal. RESULTS: Addition of NVP to the meal reduced blood glucose incremental areas under the curve irrespective of dose, reaching significance at the 7.5 g dose when added to glucose (p < 0.01), and at the 5 and 7.5 g doses when added to WB + Marg (p < 0.001). The GI values of glucose with 0, 2.5, 5, or 7.5 g of NVP were (mean ± standard error of the mean [SEM]) 100.0 ± 0.0, 83.7 ± 9.0, 77.7 ± 8.2, and 72.5 ± 5.9, respectively; the GI of the WB alone, or of WB + Marg, with 0, 2.5, 5, or 7.5 g of NVP was 71.0 ± 0.0, 66.8 ± 3.0, 47.5 ± 5.9, 37.3 ± 5.9, and 33.9 ± 3.6, respectively. CONCLUSION: Addition of NVP to different food matrices is highly effective in lowering the glycemic index of a food in a dose-responsive manner.