The impact of soluble dietary fibre on blood glucose, insulin and gut hormones in obese human subjects

The incidence of obesity and type 2 diabetes mellitus (T2D) has been on the rise and the evidence suggests that soluble dietary fibres may be helpful for obesity management and T2D prevention. Polyglycoplex (PGX), a novel, viscous polysaccharide, has been shown in several studies to promote weight loss and exert positive effects on postprandial glycemia and satiety hormone secretions. Furthermore, recent evidence suggests a role of dietary fibres in appetite glycemic control, which may be partly mediated by gut hormones such as glucagon-like peptide-1 (GLP-1), gastric inhibitory polypeptide (GIP), amylin, leptin, ghrelin, peptide YY (PYY) and pancreatic polypeptide (PP). These substances may aid weight loss and the maintenance of a constant plasma insulin level, which is important for obese and T2D patients. Healthy, overweight individuals (Body Mass Index (BMI) > 27 kg/m2) were recruited for this study. Participants were randomized for 13 weeks to receive supplements, containing either 750 mg of PGX (Treatment group, n=76) or 750 mg of cellulose (Placebo group, n=72). The participants were asked to take six capsules with water before each meal. At baseline (week 0) and at week 13 of the study, after 12 hours of overnight fasting, participants consumed a test meal. Participants did not consume PGX or placebo capsules prior to breakfast on the days of a meal tolerance test. Blood samples were collected at time 0, and at 15, 30, 45, 60, 120, and 240 min after the test meal. Although previous studies carried out on the granular form of PGX suggest that it may promote acute effects of weight loss and reductions in postprandial glycemia, in this specific study, capsulated PGX did not show a statistically significant effect on body weight, BMI, blood glucose, insulin, or other hormones, in comparison with placebo. Nevertheless, PGX had statistically significant improvements for GIP and showed some positive trends in changes of leptin over ghrelin through the cross-sectional analysis. A recent study showed that PGX capsules may be more suitable for maintaining body weight and blood glucose levels due to its delayed effects and convenience.Land and Food Systems, Faculty ofGraduat