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Effect on body weight and composition in overweight/obese Australian adults over 12 months consumption… Pal, Sebely; Ho, Suleen; Gahler, Roland J; Wood, Simon Nov 17, 2016

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RESEARCH Open AccessEffect on body weight and composition inoverweight/obese Australian adults over12 months consumption of two differenttypes of fibre supplementation in arandomized trialSebely Pal1*, Suleen Ho1, Roland J. Gahler2 and Simon Wood1,2,3AbstractBackground/Objectives: Higher fibre intakes are associated with risk reduction for chronic diseases. However,many people find difficulty in consuming sufficient fibre through their diet. Supplements may be an effectivealternative. We aimed to investigate the effects of PolyGlycopleX® (PGX®), a proprietary polysaccharide complex anda proprietary Psyllium product (PgxSyl™) (PSY) on diet, body weight and composition in overweight and obeseindividuals.Subjects/Methods: This was a double-blind 52 weeks study with 159 people randomized to 3 groups: control(rice flour); PGX (PGX) and proprietary psyllium (PSY). Participants did not change any of their usual habits or dietexcept they consumed 5 g of supplement taken with a total of 500 ml of water 5–10 min before meals.Results: Weight was significantly lower in the PGX group compared to control at 3 (−1.6 kg [0.57, 2.67, p = 0.003]),6 (−2.6 kg [1.01, 4.13, p = 0.001]) and 12 months (−2.6 kg [0.59, 4.64, p = 0.012]) and in the PSY group compared tocontrol group at 3 (−1.1 kg [0.07, 2.12, p = 0.037]) and 6 months (−2.4 kg [0.95, 3.93, p = 0.002]). This was adifference of − 2.8% for the PGX group and − 1.5% for the PSY group compared to control after 12 monthssupplementation. Body Fat was significantly lower in PGX compared to control at 6 (−1.8 kg [0.63, 2.95, p = 0.003])and 12 months (−1.9 kg [0.43, 3.36, p = 0.012]) and in PSY compared to control at 6 (−1.9 kg [0.84, 3.04, p = 0.001])and 12 months (−1.4 kg [0.08, 2.71, p = 0.038]).Conclusions: PGX was better than PSY at maintaining dietary changes and weight loss over the 12 monthintervention period, with no change to exercise. A simple strategy of PGX supplementation may offer an effectivesolution to long-term weight-loss and then management without the need for other nutrient modification.Trial registration: ANZCTR: ACTRN12611000415909. Registered 20 April 2011Keywords: Obesity, Fibre, PGX, Psyllium, Body composition* Correspondence: s.pal@curtin.edu.au1School of Public Health, Curtin University, GPO Box U1987, Perth, 6845 WA,AustraliaFull list of author information is available at the end of the article© The Author(s). 2016 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, andreproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link tothe Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Pal et al. Nutrition & Metabolism  (2016) 13:82 DOI 10.1186/s12986-016-0141-7BackgroundDietary fibre recommendations for adults in Australia,Canada and the USA are 25–30 g/d to be consumedfrom fibre-rich foods [1]. However it is estimated thatthese countries’ adults consume approximately 15–25 gof dietary fibre/d [2, 3]. Epidemiological and cohort stud-ies have consistently revealed that higher fibre intakes arecorrelated with lower body weight, body mass index(BMI), waist circumference [4, 5], improved lipid profiles[2, 6–14], glycaemia and insulinaemia [15]; indicating thebenefits and risk reduction for metabolic syndrome,cardiovascular disease and type 2 diabetes.Although the benefits of fibre are well known, people,in general, find it difficult to eat the required amounts offibre by increasing fruit and vegetable intake [16]. There-fore, fibre supplements can provide an easy, cost effect-ive method for increasing fibre intake without the needfor other major nutrient modifications.PolyGlycopleX® (PGX®)PolyGlycopleX (PGX) is a novel, highly viscous functionalnon-starch polysaccharide complex, with developingviscosity, manufactured by a proprietary process (Enviro-Simplex®) from konjac (glucomannan), sodium alginateand xanthan gum. Adding 2.5–5 g of PGX to a meal ishighly effective in reducing postprandial glycaemia, lower-ing the glycaemic index of food [17] and modifying satietyhormones in healthy adults [18].Psyllium fibrePsyllium is one of the most widely used fibre supple-ments in Australia because it is reasonably cheap, isavailable in several flavours and sold as powdered drinkmixes, capsules or wafers. Psyllium has advantages overother types of soluble fibre because it is less readilyfermented and therefore causes less flatulence and ab-dominal bloating [19]. Psyllium is a soluble fibre and hasbeen evaluated in various human studies for beneficialeffects on glucose and insulin homeostasis, lipids andlipoprotein, body weight, body composition and appetite[20–28]. Therefore PSY was chosen as a positive controlto examine whether PGX would be as good as or betterthan PSY. Psyllium intake was reviewed (2012) for itseffect on metabolic syndrome [29]. The authors con-cluded, “Collectively, research to date does support thenotion that the consumption of psyllium may providebenefits to many components of the metabolic syndrome.”Psyllium fibre seems to improve body weight in animals[30] but human studies remain controversial, with mostshowing no improvement on body weight and body com-position after psyllium consumption [21, 24–26].PGX is the most viscous soluble fibre, 3–5 times moreviscous than any known individual polysaccharide [31].Although it is considered natural, it is a blend of 3different fibres: konjac (glucomannan), sodium alginateand xanthan gum. Psyllium has a similar physical ap-pearance as PGX in its powder form but has a lowerviscosity.Both PGX and psyllium are viscous fibers which ab-sorb large amounts of water and form gels that increasefeelings of fullness, [32] this may cause people to con-sume less food. The thickening of gut contents decreasesintestinal passage rates, prolongs nutrient absorptionand hence causes satiety [33], thus PGX with a greaterviscosity has a greater effect on satiety and reduced foodintake [32]. Given the greater viscosity, it was hypothe-sized that PGX would have better metabolic outcomesin this clinical trial.Randomized, blinded, placebo controlled clinical trialsare required to verify whether PGX® can be used for longterm weight loss programs. Therefore the aim of thisstudy was to investigate the effect of PGX on bodyweight and composition when compared to a proprietaryPsyllium (PgxSyl™) product and a placebo. Given theeffect of PGX on postprandial glycemia/insulinemia andits considerably higher viscosity, we hypothesize thatPGX will demonstrate a greater improvement of bodyweight loss and composition than the psyllium productor placebo in individuals with overweight and obesity.MethodsSubjectsIndividuals with overweight and obesity (BMI 25–47 kg/m2) were recruited from the community inPerth, Australia and screened by telephone or onlinequestionnaire. Exclusion criteria included smoking,medication and other agents that may influence lipid me-tabolism, diabetes mellitus, hypo- and hyperthyroidism,cardiovascular events within the last 6 months, majorsystemic diseases, gastrointestinal problems, weightfluctuations over the past 6 months, and participation inany other clinical trials within the last 6 months.Study designThis was a randomized, double-blind, parallel design studyover a 52 weeks period, with recruitment and the inter-vention conducted from February 2012 to September 2013.Participants were equally randomized by the trial sponsorsusing a Web site [http://www.randomization.com/] to oneof three groups (3 randomly permuted blocks): the controlgroup who consumed the placebo with their usual diet; thepsyllium group (PSY) who consumed a psyllium supple-ment with their usual diet and a PGX group (PGX) whoconsumed a PGX supplement with their usualdiet. The supplementation (InovoBiologic Inc., Calgary,Canada) consisted of either 5 g of psyllium or 5 g of PGX.Placebo consisted of 5 g rice flour, an appropriate placebodue to its low energy and fibre content but similarity inPal et al. Nutrition & Metabolism  (2016) 13:82 Page 2 of 10texture and appearance to the psyllium and PGX. All sup-plements were artificially sweetened (aspartame), naturallyflavoured (citric acid and orange) and coloured (sunsetyellow FCF). Participants were instructed to take supple-ments mixed with a minimum of 250 mL water followedby an additional 250 mL water (500 mL total), three timesdaily, 5–10 min before meals. Packages were identical andwere only marked by the participant ID (sequentiallynumbered), with the group allocation only known to thetrial sponsors to ensure blinding. All identifiable informa-tion from participants was coded to ensure privacy.The subjects attended a briefing session on how toconsume the supplement, complete food records andcomply with the study protocol as previously reported[34]. All participants were asked to maintain their usualdietary intake and physical activity for the duration ofthe study. To monitor compliance, participants com-pleted a diary to record their supplement consumptionand asked to return the empty and non-empty sachets ofthe supplements at visits.Anthropometry and body compositionMeasures of weight, height, waist and hip circumferencewere undertaken at baseline, 3, 6 and 12 months. Weight(HBF-514, Omron, Kyoto, Japan) was recorded in lightclothing without shoes and height was measured using astadiometer. Waist circumference was measured in thestanding position at the narrowest area between the lat-eral lower rib and the iliac crest. Hip measurement wastaken at the largest circumference of the lower abdomen.Total body fat, lean mass, android fat and gynoid fatwere assessed by whole body dual-energy X-ray ab-sorptiometry (DXA; Lunar Prodigy, Lunar, MadisonWI, USA) at baseline, 6 and 12 months. Android fat(fat around the abdomen) and gynoid fat (fat aroundthe hips) regions were automatically obtained by theGE Lunar Prodigy software. Body fat distribution var-ies by gender as women tend to have greater gynoidfat than men [35].Diet and physical activityParticipants completed 3-day food and drink diaries atbaseline, 3, 6 and 12 months to monitor for changes infood intake. Data were analysed with Foodworks 7Professional (Xyris Software, Australia). Participants alsocompleted the International Physical Activity Question-naire (short version) at the same time points to monitorphysical activity levels.Statistical analysisA sample size of 24 subjects/group was predicted toprovide sufficient power (80%) to detect a 3% differencein weight within a group. Calculations were based on amean weight of 80 kg and a standard deviation of 5%within a group on all eligible subjects. We recruited 53subjects/group to accommodate for 50% dropouts.Statistical analysis was undertaken using SPSS 22 forWindows (SPSS Inc., Chicago, IL, USA). Data wereexpressed as mean (± SEM) and assessed for normality.Baseline differences between groups was analysed withone-way ANOVA. Changes from baseline within a groupwere analysed with paired T-test. The data were analysedusing General Linear Models with baseline value covari-ates. If significant between groups effects were present,post hoc comparisons between the treatment groupswas made using the Least Significant Difference(LSD) method. Statistical significance was consideredat p <0.05. There were no significant differencesbetween genders when sex was used as a factor inthe analysis of variance for each parameter reported,i.e. diet, physical activity, body weight and body com-position at each time point.Patient involvementNo patients were involved in the design, recruitment toor conduct of the study or in the development of theresearch question and outcome measures. Individualresults were sent to participants. The burden of theintervention on participants was not assessed.ResultsParticipantsThe 159 participants (19 to 68 y) who met the eligibilitycriteria were randomized to one of three groups (Control,PGX, PSY) by assignment of an ID number from 001 to159 and the corresponding numbered supplement. Partici-pant flow through the study can be seen in Fig. 1. 127 par-ticipants (54 male, 73 female) completed at least 3 monthsof the study and were included in the analysis (45 inControl [24 male], 39 in PGX [15 male] and 43 in PSY[15 male]).Baseline characteristicsThere were no significant differences at baseline betweengroups for major characteristics, energy intake, macro-nutrients or fibre intake (Table 1).DietThe dietary analysis can be seen in Table 2. We observedsignificant decreases in energy intake in the PGX groupat 3 months (p = 0.001), 6 months (p = 0.009) and12 months compared to baseline (p = 0.012). Energyintake was significantly lower in the PSY group at3 months (p = 0.000), 6 months (p = 0.000) and12 months (p = 0.001) compared to baseline. Whenexamining differences between groups, energy intakewas significantly lower compared to control at3 months in the PGX® (−16.2%, p = 0.000) and PSYPal et al. Nutrition & Metabolism  (2016) 13:82 Page 3 of 10(−19.3%, p = 0.000) groups, at 6 months in PGX(−15.3%, p = 0.002) and PSY (−14.4%, p = 0.002)groups compared to control and at 12 months in thePGX group (−11%, p = 0.049) compared to control.Carbohydrate intake was significantly lower com-pared to control at 3 months in the PGX (p = 0.001)and PSY (p = 0.004) groups and at 6 months in PGX(p = 0.019) and PSY (p = 0.001) groups compared tocontrol. Fat intake was significantly lower comparedto control at 3 months in the PGX (p = 0.014) andPSY (p = 0.000) groups and at 6 months in the PGXgroup (p = 0.045) compared to control. Protein intakewas significantly lower compared to control at3 months in the PGX (p = 0.006) and PSY (p = 0.000)groups and at 6 months in the PGX® group (p =0.002) compared to control. Compared to baseline,carbohydrate intake was significantly lower for bothPGX and PSY groups at all time points. Fat and pro-tein intakes were inconsistent during the 12 monthstudy period.Dietary fibre intake from food was significantly lowercompared to control at 6 months in the PGX (p = 0.045)group. Fibre intake from food was significantly lower inthe PSY group at 6 months (p = 0.005) compared tobaseline. Total fibre intake in the PGX and PSY inter-vention groups was 15 g/day higher than fibre intakefrom food, as participants were consuming three 5 gfibre supplements each day. This was a significantincrease compared to baseline and compared to thecontrol group for both PGX and PSY groups.Physical activityPhysical activity levels did not significantly change frombaseline within any groups and there were no significantdifferences between groups at any time point (Table 3).Body weightWeight and BMI were significantly lower in the PGXgroup at 12 months compared to baseline (p < 0.05),Fig. 2a shows change in body weight Fig. 2b showsAllocated to Control(n=53)Allocated to PGX (n=53)Analysed (n=45)Not analysed (n=8)Reasons for withdrawal:Non-compliance/no longer able to commit (n=4)Unrelated health issue (n=3)Minor adverse effects (n=1)Allocated to Psyllium(n=53)Randomized (n=159)Met eligibility requirements (n=159)Analysed (n=39)Not analysed (n=14)Reasons for withdrawal:Non-compliance/no longer able to commit (n=2)Unrelated health issue (n=8)Minor adverse effects (n=1)Personal reasons (n=3)Analysed (n=43)Not analysed (n=10)Reasons for withdrawal:Not contactable (n=1)Non-compliance/no longer able to commit (n=5)Unrelated health issue (n=4)Analysed (n=38)Not analysed (n=7)Reasons for withdrawal:Unrelated health issue (n=2)Lost interest (n=3)Personal reasons (n=2)Analysed (n=32)Not analysed (n=6)Reasons for withdrawal:Not contactable (n=1)Minor adverse effects (n=1)Lost interest (n=3)Personal reasons (n=1)Analysed (n=39)Not analysed (n=4)Reasons for withdrawal:Non-compliance/no longer able to commit (n=2)Unrelated health issue (n=1)Lost interest (n=1)Analysed (n=36)Not analysed (n=3)Reasons for withdrawal:Not contactable (n=1)Unrelated health issue (n=2)Analysed (n=31)Not analysed (n=8)Reasons for withdrawal:Non-compliance/no longer able to commit (n=3)Unrelated health issue (n=2)Minor adverse effects (n=1)Lost interest (n=1)Personal reasons (n=1)Analysed (n=25)Not analysed (n=6)Reasons for withdrawal:Not contactable (n=1)Unrelated health issue (n=1)Lost interest (n=2)Personal reasons (n=2)EnrolmentAllocation3 Month Follow-up6Month Follow-up12 Month Follow-upFig. 1 Participant flow diagramPal et al. Nutrition & Metabolism  (2016) 13:82 Page 4 of 10change in BMI. Weight was significantly lowercompared to control at 3 months in the PGX (−1.7%,p = 0.007) and PSY (−1.2%, p = 0.037) groups, at6 months in PGX (−2.7%, p = 0.001) and PSY (−2.6%,p = 0.002) groups compared to control and at12 months only in the PGX group (−2.8%, p = 0.012)compared to control. BMI was significantly lowercompared to control at 3 months in the PGX (p =0.004) and PSY (p = 0.042) groups, at 6 months inPGX (p = 0.001) and PSY (p = 0.001) groups comparedto control and at 12 months only in the PGX group(p = 0.010) compared to control.Waist circumference was significantly lower (p < 0.01)in the PGX and PSY groups at 3 months, 6 months and12 months compared to baseline, Fig. 2c. Waist wassignificantly lower compared to control at 3, 6 and12 months in the PGX and PSY groups (p < 0.01) com-pared to control.Hip was significantly lower in the PGX group at 6 and12 months (p < 0.05) compared to baseline. Hip was sig-nificantly lower in the PSY group 6 months (p = 0.009)compared to baseline. Hip was significantly lower com-pared to control at 6 months in PGX (p = 0.034) andPSY (p = 0.004) groups compared to control and at12 months only in the PGX group (p = 0.008) comparedto control, Fig. 2d.WHR was significantly lower in the PGX group at 3 and6 months compared to baseline and in the PSY group at 3,6 and 12 monthsnths compared to baseline (p < 0.05).WHR was significantly lower in the PSY group comparedto control at 3 and 6 months (p < 0.05), Fig. 2e.DXA Body fatThe amount of change of body fat was significantlylower in the PSY and PGX groups at 6 months and inPGX group at 12 mo (p < 0.05) compared to baseline.Body fat was significantly lower compared to control at6 months in the PSY (p = 0.001) and PGX® (p = 0.003)groups and at 12 months in the PSY (p = 0.038) andPGX groups (p = 0.012) compared to control, Fig. 3a.Body fat % was significantly lower in the PGX and PSYgroups at 6 months compared to baseline (p < 0.05).Body fat % was significantly lower compared to controlat 6 months in the PGX (p = 0.020) and PSY (p = 0.002)groups and at 12 months in the PGX (p = 0.008) andPSY groups (p = 0.018) compared to control, Fig. 3b.Android fat was significantly lower in the PGX andPSY groups at 6 and 12 months (p < 0.05) compared tobaseline. Android fat was significantly lower comparedto control at 6 months in the PGX (p = 0.004) andPSY (p = 0.003) groups and at 12 months in the PGX(p = 0.003) and PSY groups (p = 0.005) compared tocontrol, Fig. 3c. Gynoid fat was significantly lower inthe PSY group at 6 and 12 months (p < 0.05) compared tobaseline. Gynoid fat was significantly lower compared tocontrol at 6 months in the PGX® (p = 0.028) and PSY (p =0.002) groups and at 12 months in the PGX (p = 0.010)and PSY groups (p = 0.003) compared to control, Fig. 3d.Lean mass % was significantly higher in the PGXand PSY groups at 6 months (p < 0.05) compared tobaseline. Lean mass % was significantly higher com-pared to control at 6 months in the PGX (p = 0.035) andPSY (p = 0.002) groups and at 12 months in the PGX (p =0.008) and PSY groups (p = 0.017) compared to control,Fig. 3e.Adverse eventsMinor adverse events were gastrointestinal related (e.g.flatulence, diarrhoea) with four participants withdrawingTable 1 Baseline characteristicsControl(n = 45)Psyllium(n = 43)PGX(n = 39)Gender (M/F) 24/21 15/28 15/24Age (y) 49.8 ± 1.8 49.9 ± 1.7 47.9 ± 1.9Height (cm) 171.7 ± 1.5 169.2 ± 1.6 169.8 ± 1.7Weight (kg) 94.7 ± 2.5 91.2 ± 2.2 96.2 ± 2.9BMI (kg/m2) 32 ± 0.6 31.7 ± 0.5 33.2 ± 0.7Waist (cm) 103.1 ± 1.6 101.2 ± 1.5 106 ± 2Hip (cm) 112.9 ± 1.3 114.6 ± 1.3 115.7 ± 1.5Waist Hip Ratio 0.91 ± 0.01 0.88 ± 0.01 0.92 ± 0.02Control(n = 44)Psyllium(n = 43)PGX(n = 38)aFat (kg) 37.3 ± 1.4 38.6 ± 1.2 38.3 ± 1.3Fat % 40.2 ± 1.2 40.89 ± 1.1 41.1 ± 1.2Android Fat (kg) 3.8 ± 0.2 3.5 ± 0.2 3.9 ± 0.2Gynoid Fat (kg) 6.1 ± 0.3 6.3 ± 0.2 6.2 ± 0.3Lean (kg) 53 ± 1.9 50.4 ± 1.7 52.8 ± 2.2Lean % 56.6 ± 1.2 55.8 ± 1 55.7 ± 1.2Control(n = 44)Psyllium(n = 43)PGX(n = 39)Energy (kJ/d) 8636.4 ± 294.4 8859.4 ± 318.4 8783.3 ± 261.3Carbohydrate (g/d) 209.8 ± 8.8 212 ± 8.9 209.8 ± 8.6Fat (g/day) 80.2 ± 4.2 81.2 ± 4.5 82.8 ± 3.3Protein (g/d) 101.7 ± 4 104 ± 4.7 101.6 ± 3.9Fibre (g/d) 22.6 ± 1.2 23.9 ± 1.3 21.4 ± 1.2Control(n = 40)Psyllium(n = 41)PGX(n = 35)Physical Activityb(MET/min/w)3058 ± 591 3133 ± 453 2135 ± 432Values are mean ± SEM. PGX (PolyGlycopleX) MET (Metabolic Equivalent ofTask). aOne participant in the PGX group was unable to have the DXA scan.bPhysical activity logs missing (n = 10). P values were not significant.4.184 kJ = 1 kCalPal et al. Nutrition & Metabolism  (2016) 13:82 Page 5 of 10Table 2 Dietary intake during 12 months of fibre supplementationVariable 3 months Mean change n P 6 months Mean change n P 12 months Mean change n PEnergy (kJ/d) CTR 9013.1 ± 223.6a 115.5 39 NS 8803.3 ± 282.9a 32 34 NS 8218 ± 295.4a −529.7 31 NSPSY 7272.3 ± 218b −1617.3 41 0.000 7539.2 ± 278.8b −1229.2 35 0.000 7657.1 ± 277.9ab −1202 35 0.001PGX 7556.3 ± 243.1b −1090.9 33 0.001 7453.7 ± 323.5b −1080.7 26 0.009 7315.3 ± 342.4b −1226.4 23 0.012CHO (g/d) CTR 212.6 ± 7.7a −1.6 39 NS 213.4 ± 10a 3.4 34 NS 200.5 ± 8.4 −10.3 31 NSPSY 181 ± 7.5b −31.8 41 0.002 164.7 ± 9.8b −39.9 35 0.002 183.9 ± 7.9 −26 35 0.015PGX 175.3 ± 8.4b −31.5 33 0.003 177.2 ± 11.4b −22.1 26 0.032 176.3 ± 9.7 −25.6 23 0.012Fat (g/d) CTR 83.8 ± 3.2a −0.5 39 NS 82.3 ± 4.3a −0.6 34 NS 73 ± 4 −9.5 31 NSPSY 66.9 ± 3.1b −15.6 41 0.000 72.9 ± 4.2ab −8.6 35 NS 73 ± 3.8 −9.6 35 NSPGX 72.2 ± 3.4b −9 33 NS 69.1 ± 4.9b −10.5 26 0.047 66 ± 4.7 −15.2 23 0.020Protein (g/d) CTR 109.9 ± 3.7a 6.4 39 NS 105.2 ± 4.1a 3.1 34 NS 99.4 ± 4.7 −2.1 31 NSPSY 85.9 ± 3.6b −17.6 41 0.000 96.7 ± 4ab −6.7 35 NS 88 ± 4.4 −15.3 35 0.003PGX 94.4 ± 4.1b −6.5 33 NS 85.7 ± 4.7b −15.7 26 0.004 89.2 ± 5.4 −10.2 23 NSFibre from diet (g/d) CTR 24.2 ± 1.2 0.8 39 NS 22.1 ± 1a −0.4 34 NS 21.6 ± 1.3 −1 31 NSPSY 21.4 ± 1.2 −2.3 41 NS 20.1 ± 0.9ab −2.9 35 0.005 21.6 ± 1.3 −2.4 35 NSPGX 21.6 ± 1.3 −0.6 33 NS 19.1 ± 1.1b −2.2 26 NS 21.1 ± 1.6 −1 23 NSTotal Fibre (g/d) CTR 24.2 ± 1.2a 0.8 39 NS 22.1 ± 1a −0.4 34 NS 21.6 ± 1.3a −1 31 NSPSY 36.4 ± 1.2b 12.7 41 0.000 35.1 ± 0.9b 12.1 35 0.000 36.6 ± 1.3b 12.6 35 0.000PGX 36.6 ± 1.3b 14.2 33 0.000 34.1 ± 1.1b 12.5 26 0.000 36.1 ± 1.6b 13.8 23 0.000Values are mean ± SEM with baseline as a covariate. Mean change from baseline. P values are within group differences compared to baseline. Different letters in superscript represent significant differences betweengroups p < 0.05. CHO (carbohydrate), CTR (control), PGX (PolyGlycopleX), PSY (psyllium). Dietary intake data missing at baseline or 3 months (n = 14). 4.184 kJ = 1 kCalPaletal.Nutrition&Metabolism (2016) 13:82 Page6of10from the study, two in the PGX group and two in thecontrol group. The PSY supplement was better toleratedand participants did not report any adverse effects.DiscussionThis study investigated the effects of daily consumptionof 15 g of PGX or PSY compared to control (rice flour)for 1 year. Both the PGX and PSY groups demonstratedsignificant reductions in energy and macronutrient in-take as well as significant weight loss and improvementsto body composition at 52 weeks. At12 months, energyintake and weight was significantly lower in the PGXgroup compared to control but was not significantlylower in the PSY group compared to control. Fat andprotein intake was significantly lower in the PGX groupat 3 and 6 months compared to control whereas fat andprotein intake was only significantly lower in the PSYgroup at 3 months compared to control. In this regard,the PGX group performed better than the PSY groupand was better at maintaining dietary changes andweight loss over the 12 month intervention period.We observed significant decreases in energy andmacronutrient intake within the two intervention groupsat 3, 6 and 12 months compared to baseline. Althoughparticipants were instructed not to intentionally changetheir diet, taking the supplements daily before each mealresulted in a decrease in their overall food intake(Table 1). The short term consumption of PGX has beenTable 3 Physical activity during 12 months of fibre supplementation3 months Mean change n 6 months Mean change n 12 months Mean change nCTR 2802.4 ± 449.3 −130.5 29 2868.2 ± 454.7 −141.2 32 3294.5 ± 525.6 415.4 30PSY 2933 ± 443.6 620.8 30 3009.3 ± 433.2 187 35 2879.1 ± 497.8 609.6 33PGX 2181.7 ± 470.6 751.3 27 2681.1 ± 495.5 328.2 27 2684.9 ± 619.1 194.3 22Values are mean kJ/day ± SEM with baseline as a covariate. Mean change from baseline. Physical activity data missing at either baseline and/or at follow up timepoints (n = 67). Gender ratio was unaffected at 2 males:3 females. P values were not significant. 4.184 kJ = 1 kCalFig. 2 Change in body weight and waist during12 months of fibre supplementation a Weight, b BMI, c Waist, d Hip, e WHR. Values are changesin the parameters over the 12 months and are mean ± 95% CI error bars with baseline as a covariate. *indicates within group differencescompared to baseline. Different letters represent significant differences between groups p < 0.05. 3 months n = 45 CTR, 43 PSY, 40 PGX, 6 monthsn = 38 CTR, 39 PSY, 32 PGX, 12 months n = 32 CTR, 36 PSY, 26 PGX. CTR Control, PSY Psyllium, PGX (PolyGlycopleX)Pal et al. Nutrition & Metabolism  (2016) 13:82 Page 7 of 10previously shown to reduce hunger and food consump-tion in healthy weight adolescents [32] and increasesatiety or feelings of fullness in normal weight adults[36] and women who were overweight/obese [37]. This isthought to be through its effects on appetite-regulatingpeptides glucagon-like peptide-1 and peptide YY [38] and/or due to its gel forming property that increases stomachfullness and delays gastric emptying [36].In previous retrospective observational clinical trials,overweight participants lost significant weight, fat anddecreased waist circumference compared to baselineafter taking PGX for 14 weeks in addition to healthylifestyle changes [39]. In addition, overweight subjectstaking a PGX meal replacement and a PGX supplementfor 12 weeks also experienced significant decreases inweight, waist and hip measurements compared to base-line [40]. This is in agreement with the current studyand at the same daily dose of 15 g of PGX. However, incontrast to these two previous trials, we were able todemonstrate significant changes in weight, waist andbody fat in the PGX group compared to the controlgroup for 52 weeks and without prescribing any otherlifestyle changes.Psyllium is widely used as a fibre supplement as it isreadily available and well tolerated, however findings onthe effect on metabolic syndrome risk factors have beeninconclusive [29]. De Bock et al. [41], conducted a6 weeks intervention crossover study with 6 g/day ofpsyllium supplementation in healthy adolescents and didnot observe any significant change in dietary intake,weight or body fat percentage. In a study by Pal et al.[20] psyllium supplementation (3.4 g psyllium per 12 gdose of Metamucil® with 250 ml of water) caused signifi-cant decreases in body weight, BMI and body fatcompared to the control group after 12 weeks but nodifferences in waist circumference. In the current study,the PSY group significantly decreased body weight, BMIand body fat compared to the control group but we alsoobserved significant decreases in energy intake and waistcircumference. However, in contrast to the studies by deBock et al. [41] and Pal et al. [20], our supplement was 5 gper dose taken with 500 ml of water. The size of the doseFig. 3 Change in body composition during12 months of fibre supplementation a Fat, b Fat percentage, c Android Fat, d Gynoid Fat, e LeanMass. Values are changes in the parameters over the 12 months and are mean ± 95% CI error bars with baseline as a covariate. *indicates withingroup differences compared to baseline. Different letters represent significant differences between groups p < 0.05. 6 months n = 37 CTR, 37 PSY,31 PGX, 12 months n = 32 CTR, 35 PSY, 26 PGX. CTR Control, PSY Psyllium, PGX (PolyGlycopleX)Pal et al. Nutrition & Metabolism  (2016) 13:82 Page 8 of 10or the amount of water consumed may be an importantfactor when taking a fibre supplement and an adequateamount needs to be taken to be effective.The weight loss and changes to body compositionobserved may be due to the changes in dietary intake aswell as the possible effect of PGX on slowing gastricemptying and absorption of nutrients in the small intes-tine [42]. In the current study, energy intake demon-strated significant positive relationships (p < 0.05) withbody weight (r = 0.360), abdominal fat (r = 0.223) andlean mass (r = 0.378) across all participants. A PGX con-taining diet has also been shown to lower food intake andslow weight gain in rats compared to cellulose or inulincontaining chow [43]. PSY has also been shown to increasefullness [27] but has a lower viscosity than PGX [39].One of the strengths of this study was the duration; a12 month intervention period. Comparable studies haveonly been conducted for 14 weeks. This allowed us toinvestigate the long term effects of the supplements,especially on weight maintenance. This was a double-blinded randomized study and supplements were packedin identical foil sachets; however, due to the differentcharacteristics of the supplements, participants may havebeen able to guess if they were taking a supplement orthe control. The majority of participants were femaledespite a higher prevalence of overweight and obesity inmales in the Australian setting [44], so results may notbe generalizable to males or populations in other coun-tries. Other limitations include our reliance on partici-pant honesty and accuracy when completing food diariesand reporting of supplement consumption. Care mustbe taken when drawing conclusions from self-reporteddata, however more reliable methods of measuring foodintake with low participant burden are lacking. Theintervention was not combined with any other lifestylemodification advice, thus it would be simple for con-sumers to incorporate into their lifestyle or there couldbe added benefits if the supplements were combinedwith healthy lifestyle advice.ConclusionsThe effects of PGX on appetite-regulating peptides mayalso play a role in reducing dietary intake. Taking thesesupplements before meals was a relatively easy task forpeople to incorporate into their daily routine and wouldbe a simple intervention to implement. We observedsimilar results between PGX and PSY supplements butwhen compared to the control group, the PGX supple-ment was superior in terms of increased weight loss anddecreased energy intake. Therefore, regular consumptionof a PolyGlycopleX® or the proprietary psyllium supple-ment is a simple and effective method to reduce bodyweight and body fat in people with overweight or obes-ity. Further work on these two proprietary productsshould be undertaken to investigate these initial findingsin other population groups and in other formats, forexample, a PGX softgel or a psyllium softgel.AbbreviationsBMI: Body mass index; CHO: Carbohydrate; CTR: Control; DXA: Dual-energyX-ray absorptiometry; LSD: Least significant difference; PGX: PolyGlycopleX;PSY: Psyllium; WHR: Waist to hip ratioAcknowledgmentsPGX®, PolyGlycopleX® and EnviroSimplex® are registered trademarks ofInovoBiologic Inc., Calgary, Canada. The proprietary Psyllium product(PgxSyl™) (PSY) was formulated by InovoBiologic Inc. We thank Michael Lyon,MD for helping with the design of this study. We thank all the participantsfor their time and contributions to this study.FundingFinancial support for the submitted work from Factors Group Australia PtyLtd, which had no role in data collection, analysis and interpretation.Availability of data and materialsData is available on request.Authors’ contributionsSP, SW, and RJG designed research; Jenny McKay and SH conductedresearch; SH analysed data; SP, SH, SW, and RJG wrote the paper; SP and SHhad primary responsibility for final content. All authors read and approvedthe final manuscript.Competing interestsRJG owns the Factors Group of Companies, which retains an interest inPGX®. SW receives consulting fees from InovoBiologic Inc.Consent for publicationNot applicable.Ethics approval and consent to participateThis study was approved by and conducted in accordance with the ethicalstandards of Curtin Human Research Ethics Committee (HR41/2011). Writtenconsent was obtained from all participants.Author details1School of Public Health, Curtin University, GPO Box U1987, Perth, 6845 WA,Australia. 2Factors Group Research, Burnaby, Canada. 3University of BritishColumbia, Vancouver, Canada.Received: 23 June 2016 Accepted: 9 November 2016References1. Marlett JA, McBurney MI, Slavin JL. Position of the American DieteticAssociation: health implications of dietary fiber. J Am Diet Assoc.2002;102:993–1000.2. National Health and Medical Research Council. Australian Dietary Guidelines.Canberra: National Health and Medical Research Council; 2013.3. US Department of Agriculture US Department of Health and HumanServices. Dietary Guidelines for Americans. Washington: US GovernmentPrinting Office; 2005.4. Du H, DL V d A, Boshuizen HC, Forouhi NG, Wareham NJ, Halkjaer J, et al.Dietary fiber and subsequent changes in body weight and waistcircumference in European men and women. Am J Clin Nutr. 2010;91:329–36.5. Newby PK, Maras J, Bakun P, Muller D, Ferrucci L, Tucker KL. Intake of wholegrains, refined grains, and cereal fiber measured with 7-d diet records andassociations with risk factors for chronic disease. Am J Clin Nutr.2007;86:1745–53.6. Wu H, Dwyer KM, Fan Z, Shircore A, Fan J, Dwyer JH. Dietary fiber andprogression of atherosclerosis: the Los Angeles Atherosclerosis Study.Am J Clin Nutr. 2003;78:1085–91.7. Lairon D. Macronutrient intake and modulation on chylomicron productionand clearance. Atheroscler Suppl. 2008;9:45–8.Pal et al. Nutrition & Metabolism  (2016) 13:82 Page 9 of 108. Kan H, Stevens J, Heiss G, Klein R, Rose KM, London SJ. Dietary fiber intakeand retinal vascular caliber in the atherosclerosis risk in communities study.Am J Clin Nutr. 2007;86:1626–32.9. Lairon D, Arnault N, Bertrais S, Planells R, Clero E, Hercberg S, et al. Dietaryfiber intake and risk factors for cardiovascular disease in French adults.Am J Clin Nutr. 2005;82:1185–94.10. Venn BJ, Mann JI. Cereal grains, legumes and diabetes. Eur J Clin Nutr.2004;58:1443–61.11. Weickert MO, Pfeiffer AF. Metabolic effects of dietary fiber consumption andprevention of diabetes. J Nutr. 2008;138:439–42.12. McKeown NM, Meigs JB, Liu S, Wilson PW, Jacques PF. Whole-grain intake isfavorably associated with metabolic risk factors for type 2 diabetes andcardiovascular disease in the Framingham Offspring Study. Am J Clin Nutr.2002;76:390–8.13. Brown L, Rosner B, Willett WW, Sacks FM. Cholesterol-lowering effects ofdietary fiber: a meta-analysis. Am J Clin Nutr. 1999;69:30–42.14. Pittler MH, Ernst E. Guar gum for body weight reduction: meta-analysis ofrandomized trials. Am J Med. 2001;110:724–30.15. Ludwig DS, Pereira MA, Kroenke CH, Hilner JE, Van Horn L, Slattery ML, et al.Dietary fiber, weight gain, and cardiovascular disease risk factors in youngadults. JAMA. 1999;282:1539–46.16. Clemens R, Kranz S, Mobley AR, Nicklas TA, Raimondi MP, Rodriguez JC, etal. Filling America’s fiber intake gap: summary of a roundtable to proberealistic solutions with a focus on grain-based foods. J Nutr.2012;142:1390S–401S.17. Jenkins AL, Kacinik V, Lyon M, Wolever TM. Effect of adding the novel fiber,PGX®, to commonly consumed foods on glycemic response, glycemic indexand GRIP: a simple and effective strategy for reducing post prandial bloodglucose levels - a randomized, controlled trial. Nutr J. 2010;9:58.18. Reimer RA, Pelletier X, Carabin IG, Lyon M, Gahler R, Parnell JA, et al.Increased plasma PYY levels following supplementation with the functionalfiber PolyGlycopleX in healthy adults. Eur J Clin Nutr. 2010;64:1186–91.19. Blackwood AD, Salter J, Dettmar PW, Chaplin MF. Dietary fibre,physicochemical properties and their relationship to health. J R Soc PromotHealth. 2000;120:242–7.20. Pal S, Khossousi A, Binns C, Dhaliwal S, Ellis V. The effect of a fibresupplement compared to a healthy diet on body composition, lipids,glucose, insulin and other metabolic syndrome risk factors in overweightand obese individuals. Br J Nutr. 2011;105:90–100.21. Ziai SA, Larijani B, Akhoondzadeh S, Fakhrzadeh H, Dastpak A, Bandarian F,et al. Psyllium decreased serum glucose and glycosylated hemoglobinsignificantly in diabetic outpatients. J Ethnopharmacol. 2005;102:202–7.22. Karhunen LJ, Juvonen KR, Flander SM, Liukkonen KH, Lahteenmaki L, SiloahoM, et al. A psyllium fiber-enriched meal strongly attenuates postprandialgastrointestinal peptide release in healthy young adults. J Nutr.2010;140:737–44.23. Anderson JW, Allgood LD, Lawrence A, Altringer LA, Jerdack GR, HengeholdDA, et al. Cholesterol-lowering effects of psyllium intake adjunctive to diettherapy in men and women with hypercholesterolemia: meta-analysis of 8controlled trials. Am J Clin Nutr. 2000;71:472–9.24. Rodriguez-Moran M, Guerrero-Romero F, Lazcano-Burciaga G. Lipid- andglucose-lowering efficacy of Plantago Psyllium in type II diabetes. J DiabetesComplications. 1998;12:273–8.25. Vuksan V, Jenkins AL, Rogovik AL, Fairgrieve CD, Jovanovski E, Leiter LA.Viscosity rather than quantity of dietary fibre predicts cholesterol-loweringeffect in healthy individuals. Br J Nutr. 2011;106:1349–52.26. Tai ES, Fok AC, Chu R, Tan CE. A study to assess the effect of dietarysupplementation with soluble fibre (Minolest) on lipid levels in normal subjectswith hypercholesterolaemia. Ann Acad Med Singapore. 1999;28:209–13.27. Turnbull W, Thomas H. The effect of a Plantago ovata seed containingpreparation on appetite variables, nutrient and energy intake. Int J ObesRelat Metab Disord. 1995;19:338–42.28. Delargy H, O’Sullivan K, Fletcher R, Blundell J. Effects of amount and type ofdietary fibre (soluble and insoluble) on short-term control of appetite.Int J Food Sci Nutr. 1997;48:67–77.29. Pal S, Radavelli-Bagatini S. Effects of psyllium on metabolic syndrome riskfactors. Obes Rev. 2012;13:1034–47.30. Galisteo M, Sanchez M, Vera R, Gonzalez M, Anguera A, Duarte J, et al. Adiet supplemented with husks of Plantago ovata reduces the developmentof endothelial dysfunction, hypertension, and obesity by affectingadiponectin and TNF-alpha in obese Zucker rats. J Nutr. 2005;135.31. Carabin IG, Lyon MR, Wood S, Pelletier X, Donazzolo Y, Burdock GA.Supplementation of the diet with the functional fiber PolyGlycoplex is welltolerated by healthy subjects in a clinical trial. Nutr J. 2009;8:9.32. Vuksan V, Panahi S, Lyon M, Rogovik AL, Jenkins AL, Leiter LA. Viscosity offiber preloads affects food intake in adolescents. Nutr Metab Cardiovasc Dis.2009;19:498–503.33. Dikeman C, Murphy M, Fahey GJ. Dietary fibers affect viscosity of solutionsand simulated human gastric and small intestinal digesta. J Nutr.2006;136:913–9.34. Pal S, Ellis V, Dhaliwal S. Effects of whey protein isolate on bodycomposition, lipids, insulin and glucose in overweight and obeseindividuals. Br J Nutr. 2010;104:716–23.35. Toss F, Wiklund P, Nordström P, Nordström A. Body composition andmortaility risk in later life. Age Ageing. 2012;41:677–81.36. Solah VA, Brand-Miller JC, Atkinson FS, Gahler RJ, Kacinik V, Lyon MR, et al.Dose–response effect of a novel functional fibre, PolyGlycopleX®, PGX®,on satiety. Appetite. 2014;77C:72–6.37. Kacinik V, Lyon MR, Purnama M, Reimer RA, Gahler RJ, Green TJ, et al. Effectof PGX, a novel functional fibre supplement, on subjective ratings ofappetite in overweight and obese women consuming a 3-day structured,low-calorie diet. Nutr Diab. 2011;1:e22.38. Grover GJ, Koetzner L, Wicks J, Gahler RJ, Lyon MR, Reimer RA, et al. Effectsof the soluble fiber complex PolyGlycopleX® (PGX®) on glycemic control,insulin secretion, and GLP-1 levels in Zucker diabetic rats. Life Sci.2011;88:392–9.39. Lyon MR, Reichert RG. The effect of a novel viscous polysaccharide alongwith lifestyle changes on short-term weight loss and associated risk factorsin overweight and obese adults: an observational retrospective clinicalprogram analysis. Altern Med Rev. 2010;15:68–75.40. Reichert RG, Reimer RA, Kacinik V, Pal S, Gahler RJ, Wood S. Mealreplacements and fibre supplement as a strategy for weight loss. ProprietyPGX® meal replacement and PGX® fibre supplement in addition to a calorie-restricted diet to achieve weight loss in a clinical setting. Biotechnol GenetEng Rev. 2013;29:221–9.41. De Bock M, Derraik J, Brennan C, Biggs J, Smith G, Cameron-Smith D, et al.Psyllium supplementation in adolescents improves fat distribution & lipidprofile: A randomized, participant-blinded, placebo-controlled, crossovertrial. PLoS ONE. 2012;7, e41735.42. Matulka RA, Lyon MR, Wood S, Ann Marone P, Merkel DJ, Burdock GA. Thesafety of PolyGlycopleX (PGX) as shown in a 90-day rodent feeding study.Nutr J. 2009;8:1.43. Grover GJ, Koetzner L, Wicks J, Gahler RJ, Lyon MR, Reimer RA, et al. Effectsof the soluble fiber complex PolyGlycopleX® on glucose homeostasis andbody weight in young Zucker diabetic rats. Front Pharmacol. 2011;2:47.44. Australian Bureau of Statistics. Australian health survey: First results 2011–2012, cat. no. 4364.0.55.001. Canberra: Australian Bureau of Statistics; 2012.•  We accept pre-submission inquiries •  Our selector tool helps you to find the most relevant journal•  We provide round the clock customer support •  Convenient online submission•  Thorough peer review•  Inclusion in PubMed and all major indexing services •  Maximum visibility for your researchSubmit your manuscript atwww.biomedcentral.com/submitSubmit your next manuscript to BioMed Central and we will help you at every step:Pal et al. Nutrition & Metabolism  (2016) 13:82 Page 10 of 10


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