***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND Previous studies showed that polydextrose has physiologic effects similar to those of dietary fiber . OBJECTIVE Ingestion of 4 , 8 , and 12 g polydextrose/d was studied to determine the physiologic effects in Chinese subjects . DESIGN In a placebo-controlled , r and omized , double-blind study , we evaluated the effects of polydextrose ingestion on clinical biochemistry indexes , glycated hemoglobin , glucose tolerance , the glycemic index , bowel function , stool weight and pH , short-chain fatty acid production , fecal microflora , and cecal mucosa cell proliferation . RESULTS Polydextrose had no significant effect on blood biochemistry indexes . Ingestion of 12 g polydextrose plus 50 g glucose result ed in a glycemic index of 89 % ( compared with a glycemic index of 100 % after ingestion of 50 g glucose ) . Bowel function ( frequency and ease of defecation ) improved significantly and there were no reports of abdominal distention , abdominal cramps , diarrhea , or hypoglycemia . Fecal weight ( wet and dry ) increased and fecal pH decreased proportionally to polydextrose intake . Short-chain fatty acid production-notably that of butyrate , isobutyrate , and acetate-increased with polydextrose ingestion . There were substantial changes in fecal anaerobes after polydextrose intake . BACTEROIDES : species ( B. fragilis , B. vulgatus , and B. intermedius ) decreased , whereas LACTOBACILLUS : and BIFIDOBACTERIUM : species increased . The cecal mucosa whole-crypt labeling index increased , with colonocyte proliferation mainly occurring in base compartments , which provided an indirect confirmation of butyrate production in the colon . CONCLUSION Polydextrose ingestion had significant dietary fiber-like effects with no laxative problems The gut peptide glucagon-like peptide 1(7 - 36 ) amide ( GLP-1 ) is released into the circulation after food intake . GLP-1 has been shown to have an incretin effect and inhibits gastrointestinal motility in humans . In rats , intracerebral administration of GLP-1 results in reduced food intake .  Obese humans have been found to have an attenuated plasma GLP-1 response to a mixed meal . To approximate the physiologic state , GLP-1 or saline was administered intravenously and r and omly at the beginning of a test meal served on a universal eating monitor to 6 obese subjects to test our hypothesis that GLP-1 influences termination of food intake ( and thus food intake during a meal ) and feelings of satiety in humans . As a marker for gastric emptying , 1.5 g acetaminophen was given at the start of the meal . Blood sample s for analysis of acetaminophen , insulin , glucose , glucagon , and C-peptide were obtained . Hunger , fullness , and food choice were assessed with visual analogue scales and food-choice question naires . GLP-1 infusion result ed in a prolonged period of reduced feelings of hunger , desire to eat , and prospect i ve consumption after the meal . The rate of gastric emptying was slower during infusion of GLP-1 . Postpr and ial blood glucose concentrations were reduced during the GLP-1 infusion , but the amount of energy consumed , eating rate , and plasma concentrations of insulin , glucagon , and C-peptide were unchanged . GLP-1 given exogenously at the start of a meal did not seem to affect meal termination or the amount of food eaten . However , postpr and ial feelings of hunger decreased , suggesting that exogenous GLP-1 may influence feelings of hunger and satiety in humans Previous studies have reported that polydextrose can reduce food intake ; however , the optimal dose required to achieve this effect is currently unknown . The present study investigated the effects of consuming a range of doses of polydextrose on appetite and energy intake ( EI ) using a r and omised within-subject , cross-over design . For this purpose , twenty-one participants ( n 12 men , n 9 women ) consumed an 837 kJ liquid preload containing 0 g ( control ) , 6.3 , 12.5 or 25 g polydextrose .  Subjective appetite ratings were collected using visual analogue scales and an ad libitum test meal was served 90 min later . Participants recorded EI for the remainder of the day in a food diary . Test meal EI following the control preload ( 5756 ( sem 423 ) kJ ) was significantly higher than following the 6.3 g ( 5048 ( sem 384 ) kJ ) , 12.5 g ( 4722 ( sem 384 ) kJ ) and 25 g ( 4362 ( sem 316 ) kJ ) preloads ( P < 0.05 ) , and EI following the 6.3 g preload was significantly higher than following the 25 g preload ( P < 0.01 ) . There were no differences in self-reported EI during the remainder of the day between the preloads containing the varying doses of polydextrose .  Total EI ( breakfast+preload+ad libitum test meal+remainder of the day ) was significantly higher when the control preload was consumed ( 12,051 ( sem 805 ) kJ ) compared with either the 12.5 g ( 10,854 ( sem 589 ) kJ ) or 25 g ( 10,658 ( sem 506 ) kJ ) preload ( P < 0.05 ) . These differences in EI were not accompanied by corresponding differences in subjective appetite ratings . In summary , polydextrose effectively reduces subsequent EI in a dose-dependent manner The effect of meals containing Quorn myco-protein or chicken upon satiety and satiation were investigated in 18 lean , healthy male and female subjects using a within-subjects design . Both meals were design ed to be similar in every respect with the exception of dietary fibre content ( 11 vs 3 g ) . Following consumption of a lunch containing Quorn myco-protein ( high fibre ) subsequent energy intake at an evening ad libitum test meal was reduced by 18 % ( P < 0.001 ) when compared with the response to an isocaloric chicken-containing ( low-fibre ) lunch . Using the Universal Eating Monitor ( a device which weighs continuously the portion of food being consumed ) the within-meal effects of a lunch containing Quorn or chicken were investigated . This study showed that during consumption , Quorn elicited similar eating behaviour when compared to a chicken meal .  Amount selected , overall eating rate and the decrease in motivation to eat did not differ between the Quorn and control conditions . These two studies show that Quorn ( high-protein , dietary fibre combination ) has a strong impact on late satiety , but is similar in its effects during and immediately after consumption . These data have clear implication s for the use of Quorn myco-protein for the control of appetite and body weight Background Soluble fibre has been proposed to suppress appetite-related perceptions and it could thus contribute favourably to the regulation of energy intake and the increasing obesity problem . Objective To investigate the effect of an oat ingredient rich in β-glucan on perceived satiety at different dietary fibre ( DF ) concentrations , energy levels and viscosity levels . Design A total of 29 healthy volunteers , age 19–39 , mean BMI 23.2 kg/m2 participated in this study . Measurement of subjective perceptions ( satiety , fullness , hunger , desire to eat something/the sample food and thirst ) was performed during a 180-min period after ingestion of the sample . There were altogether six sample s : two beverages without fibre at energy levels 700 and 1,400 kJ ; two beverages containing 5 or 10 g oat DF ( 2.5 and 5 g oat β-glucan , respectively ) at energy level 700 kJ , one beverage containing 10 g oat DF/1,400 kJ and one beverage containing 10 g enzymatically treated oat DF with low viscosity at energy level 700 kJ. Each beverage portion weighted 300 g. The order of the sample s was r and omised for each subject and evaluated during six separate days . The results are reported in three sets of sample s : ‘ fibre ’ , ‘ energy ’ and ‘ viscosity ’ . Results In the fibre set , the beverages containing 5 or 10 g of fibre had a larger area under curve ( AUC ) for perceived satiety and smaller AUC for hunger compared to the beverage without fibre , but no significant dose – response relationship was detected . Increasing the energy content from 700 to 1,400 kJ in the energy set did not affect the satiety-related perceptions . In the viscosity set , the beverage with low-viscosity β-glucan increased satiety-related perceptions from no fibre containing beverage , but less compared to the beverage with the same amount of fibre and higher viscosity . Conclusions Addition of an oat ingredient rich in β-glucan and high viscosity of beverages enhance post-meal satiety induced by beverages . The effect was , however , not related to the amount of ingested fibre or energy Endothelial function , measured by flow-mediated dilatation ( FMD ) , predicts cardiovascular events and is impaired postpr and ially . The objective of this study was to evaluate the effects of changes in composition or duration of ingestion of a meal , which slows gastric emptying and /or small intestinal nutrient exposure , on postpr and ial endothelial function . Twelve healthy subjects ( 6 male , 6 female ; 33 ± 6 yr ) were each studied on three occasions , in a r and omized crossover design . After an overnight fast , subjects consumed a [(13)C]octanoic acid-labeled mashed potato meal ( " meal 1 " ) , or meal 1 mixed with 9 g guar ( " meal 2 " ) within 10 min , or meal 1 divided into 12 equal portions over 60 min ( "  meal 3 " ) . Brachial artery FMD was measured every 30 min for 120 min . Blood glucose , serum insulin , and gastric emptying ( breath test ) were evaluated for 240 min . Data are means ± SE . Compared with meal 1 , meal 2 was associated with slower gastric emptying ( half-emptying time 285 ± 27 vs. 208 ± 15 min , P < 0.05 ) , lower postpr and ial blood glucose and insulin ( P < 0.001 for both ) , and a delayed , but more sustained , suppression of FMD ( P < 0.001 ) . After meal 3 , both glycemic increment and reduction in FMD were less than after meal 2 ( P < 0.05 for both ) . The decrement in FMD was directly related to the increment in blood glucose ( r = 0.46 , P = 0.02 ) . We conclude that , in health , postpr and ial FMD is influenced by perturbation of gastric emptying and the duration of meal consumption , which also impact on glycemia To define the type of dietary fibre of fibre analogue with the greatest potential use in diabetic treatment , groups of four to six volunteers underwent 50-g glucose tolerance tests ( GTT ) with and without the addition of either guar , pectin , gum tragacanth , methylcellulose , wheat bran , or cholestyramine equivalent to 12 g fibre . The addition of each substance significantly reduced blood glucose concentration at one or more points during the GTT and generally reduced serum insulin concentrations . The greatest flattening of the glucose response was seen with guar , but this effect was abolished when hydrolysed non-viscous guar was used . The reduction in the mean peak rise in blood glucose concentration for each substance correlated positively with its viscosity ( r = 0.926 ; P less than 0.01 ) , as did delay in mouth-to-caecum transit time ( r = 0.885 ; P less than 0.02 ) . Viscous types of dietary fibre are therefore most likely to be therapeutically useful in modifying postpr and ial hyperglycaemia The objective was to determine the effects of dietary fibre with bulking , viscous and gel-forming properties on satiation , and to identify the underlying mechanisms . We conducted a r and omised crossover study with 121 men and women . Subjects were healthy , non-restrained eaters , aged 18 - 50 years and with normal BMI ( 18.5 - 25 kg/m² ) . Test products were cookies containing either : no added fibre ( control ) , cellulose ( bulking , 5 g/100 g ) , guar gum ( viscous , 1.25 g/100 g and 2.5 g/100 g ) or alginate ( gel forming , 2.5 g/100 g and 5 g/100 g ) . Physico-chemical properties of the test products were confirmed in simulated upper gastrointestinal conditions . In a cinema setting , ad libitum intake of the test products was measured concurrently with oral exposure time per cookie by video recording . In a separate study with ten subjects , 4 h gastric emptying rate of a fixed amount of test products was assessed by ¹³C breath tests . Ad libitum energy intake was 22 % lower for the product with 5 g/100 g alg 
    Output:
    
This study suggests that soluble fibres are not all created equal .