9.50 � Five randomised controlled trials were identified that presented evidence on resistant starch supplementation in relation to faecal Bifidobacterium spp. content (Jenkins et al., 1999c; Bouhnik et al., 2004; Pasman et al., 2006; Fastinger et
al., 2008; Beards et al., 2010). No further trials were identified in the update search
(Colo-rectal health review). The data on measures of faecal bacteria content were insufficiently comparable to allow a meta-analysis to be performed. Three trials supplemented subjects’ diets with chemically modified resistant starch (RS4) (Pasman et al., 2006; Fastinger et al., 2008; Beards et al., 2010), the other trial supplemented subjects’ diets with either raw resistant starch (RS2) (Jenkins et al.,
1999c) or retrograde resistant starch (RS3) (Jenkins et al., 1999c; Bouhnik et al., 2004).
9.51 No significant effect of supplementation with any of the resistant starches on faecal Bifidobacterium spp. content is demonstrated.
Resistant starch (RS , RS and RS ) and faecal bacteria 2 3 4
•
No effect•
Adequate evidencePolyols
Colo-rectal health
9.52 Three randomised controlled trials were identified that presented evidence on polyol supplementation in relation to faecal weight (van Es et al., 1986; Sinaud et
al., 2002; Gostner et al., 2005). The data were insufficiently comparable to enable
a meta-analysis to be performed. No further trials were identified in the update search (Colo-rectal health review).
9.53 Two trials report an effect of lactitol at 50g/d or maltitol at 100g/d supplementation on increasing faecal wet weight (van Es et al., 1986; Sinaud et al., 2002). One trial reports no significant effect of the polyol isomalt at 30g/d on faecal weight (Gostner et al., 2005). From these trials, polyol intake is found to have a small faecal bulking effect with the resulting increase in faecal wet weight being 0.5 to 1g per 1g of polyol consumed.
Polyols and faecal weight
•
Effect•
Limited evidence•
The direction of the effect demonstrates higher consumption of polyols ispotentially beneficial to health, although any effect is likely to be limited by the low levels of polyols in the diet
•
The effect is potentially biologically relevant9.54 Three randomised controlled trials were identified that presented evidence on polyol supplementation in relation to faecal bacteria content (Ballongue et
al., 1997; Gostner et al., 2005; Finney et al., 2007). The data were insufficiently
comparable to enable a meta-analysis to be performed. No further trials were identified in the update search (Colo-rectal health review).
9.55 Two trials report lactitol at 20g/d and the polyol isomalt at 30g/day to increase faecal Bifidobacterium content (Ballongue et al., 1997; Gostner et al., 2005). In the other trial supplementation of lactitol at 5 or 10g/day has no significant effect on faecal bacterial content (Finney et al., 2007).
Polyols and faecal bacteria content
•
Effect•
Limited evidence•
Whether the effect is beneficial or of biological relevance is currently unclear 9.56 � Three randomised controlled trials were identified that presented evidence onpolyol supplementation in relation to faecal pH (Ballongue et al., 1997; Gostner et
al., 2006; Finney et al., 2007). The data were insufficiently comparable to enable
a meta-analysis to be performed. No further trials were identified in the update search (Colo-rectal health review).
9.57 � Two trials report an effect of lactitol supplementation on decreasing faecal pH at doses of 10g/day or more. The other trial reports no significant effect of the polyol isomalt on faecal pH (Gostner et al., 2006).
Polyols and faecal pH
•
No effect•
Limited evidence9.58 � Three randomised controlled trials were identified that presented evidence on polyol supplementation in relation to faecal short chain fatty acid content (Ballongue et al., 1997; Gostner et al., 2006; Finney et al., 2007). The data were insufficiently comparable to enable a meta-analysis to be performed. No further trials were identified in the update search (Colo-rectal health review).
9.59 � One trial reports an effect of lactitol supplementation on increasing faecal acetate and lowering faecal propionate content (Ballongue et al., 1997). One trial reports no significant effect of supplementation with the polyol isomalt on faecal short chain fatty acid content (Gostner et al., 2006). It is not possible to determine the effect of the other trial as it did not report the necessary data (Finney et al., 2007).
Polyols and faecal short chain fatty acid content
•
No effect•
Limited evidencePolydextrose
Colo-rectal health
9.60 � One randomised controlled trial was identified that presented evidence on polydextrose supplementation in relation to faecal weight (Zhong et al., 2000). One trial was identified in the update search (Vester Boler et al., 2011) (Colo- rectal health review; Update search). One trial was identified as a consequence of consultation on the draft report (Timm et al., 2013). It was not possible to perform a meta-analysis as one trial did not provide the necessary variance data (Vester Boler et al., 2011).
9.61 � All three trials demonstrate an effect of polydextrose supplementation (8 to 21g/day) on increasing faecal wet weight. The faecal bulking effect in these trials ranges between 1 and 3g faecal wet weight per 1g of polydextrose consumed.
Polydextrose and faecal weight
•
Effect•
Limited evidence•
The direction of the effect demonstrates higher consumption of polydextrose is potentially beneficial to health, although any effect would be limited by the low levels of polydextrose in the diet•
The effect is potentially biologically relevant9.62 � Two randomised controlled trials were identified that presented evidence on polydextrose supplementation in relation to faecal Bifidobacterium spp. content (Zhong et al., 2000; Hengst et al., 2008). Two trials were identified in the update search (Vester Boler et al., 2011; Costabile et al., 2012). The data were insufficiently comparable to enable a meta-analysis to be performed (Colo-rectal health review; Update search).
9.63 � One trial demonstrates a dose-response effect of polydextrose supplementation (4-12g/day) on increasing faecal Bifidobacterium content and reducing the number of Bacteriodes (Zhong et al., 2000). Another trial also demonstrates an effect of polydextrose supplementation (21g/day) on increasing faecal Bifidobacterium content (Vester Boler et al., 2011). Two trials demonstrate no significant effect of 8g/day polydextrose supplementation (Hengst et al., 2008; Costabile et al., 2012) on faecal Bifidobacterium content.
Polydextrose and faecal bacteria content
•
No effect•
Limited evidence9.64 � Two randomised controlled trials were identified that presented evidence on polydextrose supplementation in relation to faecal short chain fatty acid content (Zhong et al., 2000; Hengst et al., 2008). Two trials were identified in the update search (Vester Boler et al., 2011; Costabile et al., 2012) (Colo-rectal health review; Update search). One trial was identified as a consequence of consultation on the draft report (Timm et al., 2013). The data were insufficiently comparable to enable a meta-analysis to be performed.
9.65 � One trial demonstrates a dose-response effect of polydextrose supplementation (4-12g/day) on increasing faecal butyrate, isobutyrate, and acetate content (Zhong
et al., 2000). Two trials demonstrate an effect of polydextrose supplementation
(20-21g/day) on decreasing total faecal acetate, propionate and butyrate and total short chain fatty acid content (Vester Boler et al., 2011; Timm et al., 2013). Two trials demonstrate no effect of 8g/day polydextrose (Hengst et al., 2008; Costabile et al., 2012) on faecal short chain fatty acid content.
Polydextrose and faecal short chain fatty acid content
•
No effect•
Limited evidence9.66 Two randomised controlled trials were identified that presented evidence on polydextrose supplementation in relation to faecal pH (Zhong et al., 2000; Hengst et al., 2008). One trial was subsequently identified in the update search (Vester Boler et al., 2011) (Colo-rectal health review; Update search). One trial was identified as a consequence of consultation on the draft report (Timm et
al., 2013). A meta-analysis was performed, but the heterogeneity was above the
pre-specified cut-off of 75% (I2=96%) and, therefore, the pooled estimate has not been reported. One trial could not be included as it did not provide the necessary variance data (Vester Boler et al., 2011).
9.67 One trial demonstrates a dose-response effect of polydextrose supplementation (4-12g/day) on decreasing faecal pH (Zhong et al., 2000). One trial demonstrates an effect of polydextrose supplementation (20g/day) on decreasing faecal pH (Timm et al., 2013). The two other trials demonstrate no significant effect of polydextrose supplementation (8 or 21g/day) on faecal pH (Hengst et al., 2008; Vester Boler et al., 2011).
Polydextrose and faecal pH