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The Effect of Psyllium Husk on Intestinal Microbiota in Constipated Patients and Healthy Controls

Jalanka, Jonna; Major, Giles; Murray, Kathryn; Singh, Gulzar; Nowak, Adam; Kurtz, Caroline; Silos-Santiago, Inmaculada; Johnston, Jeffrey; de Vos, Willem; Spiller, Robin


Jonna Jalanka

Giles Major

Kathryn Murray

Gulzar Singh

Adam Nowak

Caroline Kurtz

Inmaculada Silos-Santiago

Jeffrey Johnston

Willem de Vos

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Professor of Gastroenterology


Psyllium is a widely used treatment for constipation. It traps water in the intestine increasing stool water, easing defaecation and altering the colonic environment. We aimed to assess the impact of psyllium on faecal microbiota, whose key role in gut physiology is being increasingly recognised. We performed two randomised, placebo-controlled, double-blinded trials comparing 7 days of psyllium with a placebo (maltodextrin) in 8 healthy volunteers and 16 constipated patients respectively. We measured the patients’ gastrointestnal (GI) transit, faecal water content, short-chain fatty acid (SCFA) and the stool microbiota composition. While psyllium supplement had a small but significant effect on the microbial composition of healthy adults (increasing Veillonella and decreasing Subdoligranulum), in constipated subjects there were greater effects on the microbial composition (increased Lachnospira, Faecalibacterium, Phascolarctobacterium, Veillonella and Sutterella and decreased uncultured Coriobacteria and Christensenella) and alterations in the levels of acetate and propionate. We found several taxa to be associated with altered GI transit, SCFAs and faecal water content in these patients. Significant increases in three genera known to produce butyrate, Lachnospira, Roseburia and Faecalibacterium, correlated with increased faecal water. In summary, psyllium supplementation increased stool water and this was associated with significant changes in microbiota, most marked in constipated patients.


Jalanka, J., Major, G., Murray, K., Singh, G., Nowak, A., Kurtz, C., …Spiller, R. (2019). The Effect of Psyllium Husk on Intestinal Microbiota in Constipated Patients and Healthy Controls. International Journal of Molecular Sciences, 20(2), Article 433.

Journal Article Type Article
Acceptance Date Jan 22, 2019
Online Publication Date Jan 20, 2019
Publication Date Jan 20, 2019
Deposit Date Jun 6, 2019
Publicly Available Date Jun 7, 2019
Journal International Journal of Molecular Sciences
Print ISSN 1661-6596
Electronic ISSN 1422-0067
Publisher MDPI
Peer Reviewed Peer Reviewed
Volume 20
Issue 2
Article Number 433
Keywords Prebiotics; Microbiome; Ispaghula; Constipation; Transit
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