Dietary fibre that develops viscosity in the gastrointestinal tract is capable of addressing various aspects of food intake control. The aim of this study was to assess subsequent food intake and appetite in relation to the level of viscosity following three liquid preloads each containing 5 g of either a high (novel viscous polysaccharide: PGX®), medium (glucomannan: GLM), or low (cellulose: CE) viscosity fibre.

Methods:

In this double blind randomised controlled crossover trial 31 healthy weight adolescents (25F: 6 M, age 16.1 ±0.6 years; MBI 22.2 ± 3.7 kg/m2) consumed one of three preloads 90 minutes prior to an ad libitum pizza meal. Preloads were identical in taste, appearance, nutrient content and quality of fibre and differed in their viscosity (10, 410 and 700 poise for CE, GLM and PGX® respectively).

Results:

Pizza intake was significantly lower (p = 0.008) after consumption of the high viscosity PGX® (278 ± 111 g) compare to the median viscosity GLM (313 ± 123 g) and low viscosity GC (316 ± 138 g) preloads with no difference between the GLM and CE preloads. Appetite scores, and physical symptoms and 24-hour intake did not differ among treatment groups.

Abstract:

Health benefits of viscous fibre 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.

Method:

Two open-label, randomized, controlled trials were undertaken at the Glycemic Index Laboratories, Inc, Toronto, Ontario, Canada. Two groups of 10 healthy subjects each (group 1: 5 M, 5 F; 35.6 6 13.2 y; 24.6 6 2.1 kg/m2; and group 2: 3 M, 7 F; 33.5 6 11.1 y; 26.3 6 5.2 kg/m2) were studied. Interventions at 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). 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 toWB + Marg (p,0.001). The GI values of glucose with 0, 2.5, 5, or 7.5 g of NVP were (mean6standard error of the mean [SEM]) 100.0 6 0.0, 83.7 6 9.0, 77.7 6 8.2, and 72.5 6 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 71.060.0, 66.8 63.0, 47.565.9, 37.365.9, and 33.963.6, respectively.

Abstract:

Viscous soluble dietary fibre has been demonstrated to reduce postprandial glycaemia and may promote satiety. PolyGlycopleX® (PGX®) is a highly viscous polysaccharide manufactured by reacting glucomannan with other soluble polysaccharides using a proprietary process (EnviroSimplex®). The resulting polysaccharide PGX®((a-D-glucurono-a-D-manno-b-D-manno-b-D-glucan),(a-L-gulurono-b-D-mannuronan),b-D-gluco-b-D-mannan (a-D-glucurono-a-D-manno-b-D-manno-b-D gluco),(a-L-gulurono-b-D-mannurono),b-D-gluco-b-D-mannan ) is a novel entity with the highest viscosity and water-holding capacity of currently known fibres.

Materials and Method:

A total of 29 sedentary overweight or obese adults (23 women; six men), ages 20-65 with a body mass index (BMI) range of 25 kg/m2 to 36 kg/m2 participated in a clinical weight-loss program. PGX (5 g) was consumed with 500 mL water, 5-10 minutes before each meal, 2-3 times daily for 14 weeks.

Results:

Significant reductions were observed (p<0.05) in weight (-5.79 ± 3.55 kg), waist circumference (-12.07 ± 5.56 cm), and percentage body fat (-2.43 ± 2.39%) compared to baseline values. In addition, subjects employing PGX had a significant reduction of 19.26 percent (n=17; p<0.05) and 25.51 percent (n=16; p<0.05) in total and LDL plasma cholesterol values, respec­tively, at the end of the study period.

Abstract:

A variety of dietary fibres have been shown to alter satiety hormone gene expression and secretion. The objective of this study was to examine plasma satiety hormone concentrations in healthy subjects consuming either PolyGlycopleX® (PGX®) or control (skim milk powder) for 21 days.

Methods:

A randomized, double-blind, placebo-controlled clinical study was conducted in 54 healthy male and female adults. Participants consumed 5 g per day of PGX or control for 1 week followed by 2 additional weeks of 10 g per day of assigned product (n = 27 per group). Primary outcomes measured at three visits (V1, V2 and V3) were plasma active glucagon-like peptide-1 (GLP-1) total ghrelin, peptide YY (PYY) and insulin.

Results:

There was a significant effect of visit for fasting PYY with control participants experiencing decreased PYY levels over time while PGX prevented this decline. When stratified by body mass index (BMI), PGX increased fasting PYY levels from week 1 to week 3 compared with control in participants with BMI <23 kg/m2. There was a significant effect of visit for fasting Ghrelin with levels decreasing in both PGX and control groups over time. No differences were detected in fasting GLP-1 levels. Although there was a 14% reduction in fasting insulin between V1 and V3 with PGX® this was not significantly different from control.

Abstract:

Short chain fatty acids (SCFA) are produced by bacterial fermentation of dietary fibre and have been linked to stimulation of satiety hormones and modulation of serum cholesterol. Our objective was to examine faecal SCFA concentrations in subjects consuming the functional fibre, PolyGlycopleX® (PGX®), or control (skim milk powder) for 3 wk.

Methods:

54 healthy adults participated in a randomized, double-blind, placebo controlled study. Subjects consumed 5 g/d of PGX® or control during the first week followedby 10 g/d in the second and third weeks (n=27/group). The primary outcome was SCFA concentrations in faecal samples collected at baseline (visit 1, V1), at 1 wk (V2),and at 3 wk (V3).

Results:

Acetate concentrations were higher with PGX® versus control at V3 (P=0.02). There were no differences in propionate, butyrate, valerate or caproate. There was a significant treatment effect (p=0.03) for total SCFA with higher concentrations with PGX® versus control. There was a significant negative correlation between propionate and previously measured fasting ghrelin (r= -0.29; P=0.03) at V3.

Abstract:

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.

Methods:

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.

Results:

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).

Abstract:

The effects of the novel water soluble, viscous fibre complex PolyGlycopleX® [(a-D glucurono-a-D- manno-ß-D-manno-ß-D-gluco), (a-L-gulurono-ß-D mannurono), ß-D-gluco-ß-D-mannan (PGX®)] on body weight, food consumption, glucose, insulin and glucagon-like peptide (GLP-1) levels were determined in Zucker diabetic rats (ZDFs). Such fibres are thought to improve glycemic control through increased GLP-1 induced insulin secretion.

Methods:

ZDFs were treated for 12 weeks with normal rodent chow supplemented with cellulose (control, inert fibre), inulin or PGX® at 5% wt/wt and effects on body weight, glycemic control, and GLP-1 determined. Key findings: In the fed state, PGX® reduced blood glucose compared to the other groups from week 5 until study termination while insulin was significantly elevated when measured at week 9, suggesting an insulin secretagogue effect. Fasting blood glucose was similar among groups until 7–8 weeks when levels began to climb with a modest reduction caused by PGX®. An oral glucose tolerance test in fasted animals (week 11) showed no change in insulin sensitivity scores among diets, suggesting an insulinotropic effect for PGX® rather than increased insulin sensitivity. PGX® increased plasma levels of GLP-1, while HbA1c was markedly reduced by PGX®. Body weights were not changed despite a significant reduction in food consumption induced by PGX® up to week 8 when the PGX®-treated group showed an increase in body weight despite a continued reduction in food consumption.

Results:

The key parameter showing improved glycemic control was the significant reduction of HbA1c by PGX®. The increased GLP-1 was accompanied by an increased ghrelin secretion which may have prevented the weight loss secondary to reduced food intake due to its multiple effects on energy homeostasis.

Abstract:

Viscous soluble fibres have been shown to reduce risk factors associated with type 2 diabetes and cardiovascular disease. The novel functional fibre, PolyGlycopleX® (PGX®) (InovoBiologic Inc, Calgary, Alberta, Canada) displays greater viscosity than other currently identified soluble fibres. The objective of this study was to determine if PGX lowers serum and hepatic triglycerides (TGs) in a high-sucrose-fed rat model. In this rodent model, feeding a high-sucrose diet consistently increases serum TGs. We hypothesized that consumption of PGX would attenuate hypertriglyceridemia and reduce hepatic steatosis (Fatty Liver Disease) compared with cellulose in rats fed a high-sucrose background diet.

Methods:

Male Sprague-Dawley rats were fed diets containing 65% sucrose and supplemented with either 5% cellulose (control) or 5% PGX® (wt/wt) for 43 weeks. At study termination, serum insulin and TGs, hepatic steatosis and hepatocellular (pertaining to or affecting liver cells) injury were assessed.

Results:

Body weight increased over time in both groups but weight gain was attenuated in rats fed PGX vs cellulose in weeks 2 through 22 (P < 0.05). Serum TGs did not differ from baseline for the first half of the study but consistently increased in the cellulose group thereafter. PolyGlycopleX®(PGX®) significantly reduced serum TG to near-baseline levels. At study termination, rats fed PGX had significantly lower hepatic steatosis scores (measured by Sudan black staining) compared with rats fed cellulose. Hepatocellular injury scores did not differ between the groups. PGX reduced serum TG and lipid accumulation in the liver of sucrose-fed rats. Given the growing prevalence of metabolic disease in many Western countries, the findings of this study are promising. Further examination of its potential as a fibre supplement aimed at lessening the burden of hepatic steatosis is warranted.

Abstract:

High viscosity fibre is known to exert many beneficial effects on appetite and metabolism. This study tests the potentially to help in weight management in nondieting individuals. The present study investigated the effects of the daily intake of the novel high viscosity polysaccharide (PGX®-PolyGlycopleX®) over 3 months in nondieting obese or overweight subjects. Participants were told not to change anything in their daily routine.

Methods:

The study comprised a double-blind, randomised controlled clinical trial. Participants ingested 5–15 g per day of either PGX® (29 participants) or the popularly used fibre, Inulin (30 participants) for 15 weeks. Changes in weight, waist and hip circumferences, blood lipids and other parameters were studied over the 15 weeks. Compliance and tolerance were also examined.

Results:

Differences appeared between PGX® and inulin supplementation in female participants. At the end of the study of 15 Weeks, a decrease in body weight of approximately 3.5 lbs (1.6kg) or about 2% of initial weight was determine in the PGX® group. The women in the Inulin group on average gained weight slightly, approximately 0.45 lbs (0.2kgs). Hip circumference decreased by approximately 1.1/10” (2.8 cm) in women of the PGX® group but only by approximately 1/5” (0.5 cm) in the Inulin group. Waist circumference decreased by approximately 1.5” (3.7 cm) in the PGX® group and by approximately 0.4” (1 cm) in the Inulin group for female participants.

Cholesterol levels were lower at the end of supplementation in the women of the PGX® group by approximately 8.9% for Total Cholesterol and 13.22% for LDL cholesterol. The Inulin on the other hand showed a slight rise in Total Cholesterol of approximately 1.4 % and no change for the LDL levels for female participant. No difference was noted in the number or severity of the adverse effects reported in both groups. Adverse effects were generally mild and agreed with commonly reported reactions to intake of dietary fibre.

Beneficial modest effects appeared after several weeks of daily PGX® intake in nondieting obese or overweight women compared to ingestion of comparable quantities of the commonly used Inulin fibre.

Abstract:

Dietary fibre can reduce insulin resistance, body weight and hyperlipidemia depending on fibre type, water solubility and viscosity. We wished to test this using PolyGlycopleX® (PGX®)[(a-D glucurono-a-D- manno-ß-D-manno-ß-D-gluco), (a-L-gulurono-ß-D mannurono), ß-D-gluco-ß-D-mannan (PGX®)], a natural, water soluble, non-starch polysaccharide complex that with water forms a highly viscous gel compared to other naturally-occurring dietary fibre.

Methods:

The effect of dietary PGX® vs cellulose and inulin on the early development of insulin resistance, body weight, hyperlipidemia, and glycemia-induced tissue damage in young Zucker diabetic rats (ZDFs) in fasted and nonfasted states was determined. ZDFs (5 weeks old) were fed a diet containing 5% (wt/wt) cellulose, inulin, or PGX® for 8 weeks. Body weight, lipids, insulin and glucose levels were determined throughout the study and Homeostasis Model Assessment (HOMA) was used to measure insulin sensitivity throughout the study in fasted animals. At study termination, insulin sensitivity (oral glucose tolerance test, OGTT) and kidney, liver, and pancreatic histopathology were determined.

Results:

Body weight and food intake were significantly reduced by PGX® vs inulin and cellulose. Serum insulin in fasted and non-fasted states was significantly reduced by PGX® as was non-fasted blood glucose. Insulin resistance, measured as a HOMA score, was significantly reduced by PGX® in weeks 5 through 8 as well as terminal OGTT scores in fed and fasted states. Serum total cholesterol was also significantly reduced by PGX®. PGX® significantly reduced histological kidney and hepatic damage in addition to reduced hepatic steatosis and cholestasis. A greater mass of pancreatic ß-cells was found in the PGX® group. PGX® therefore may be a useful dietary additive in the control of the development of the early development of the metabolic syndrome.

Abstract:

The development of lower-glycaemic index (GI) foods requires simple, palatable and healthy strategies. The objective of the present study was to determine the most effective dose of a novel viscous fibre supplement (PGX®) to be added to starchy foods to reduce their GI.

Reducing postprandial glycaemia and dietary glycaemic load is a recent target in the management and prevention of obesity and type 2 diabetes. The recent Diogenes study (a large multi-centre trial in Europe) showed that reduction in dietary GI and glycaemic load led to greater weight loss over 12 weeks and improved maintenance of weight loss.

Methods:

Healthy subjects (n 10) consumed glucose sugar (50 g in water × 3) and six starchy foods ( Kellogg® Corn Flakes, Quaker® Oats, McCain Fries, McCain Potatoes, Wonderwhite bread, Uncle Bens® Jasmine Rice), with a range of GI values (52–72) along with 0 (inert fibre, Inulin), 2•5 or 5 g granular PGX® dissolved in 250 ml water. GI testing according to ISO Standard 26 642-2010 was used to determine the reduction in GI.

Results:

PGX® significantly reduced the GI of all six foods (P < 0•001), with an average reduction of 19 % for the 2•5 g dose and 30 % for the 5 g dose, equivalent to a reducing the GI by 7 and 15 units, respectively. Inulin, a popular dietary fibre, had no effect on lowering the GI of the foods.

The authors concluded that: Consuming small quantities of the novel functional fibre PGX®, mixed with water at the start of a meal, is an effective strategy to reduce the GI of common foods.