Combined Flaxseed and Psyllium Supplementation Relieves Chronic Idiopathic Constipation and Alters Gut Microbiota Composition in Adults: A Randomized, Double-Blind, Placebo-Controlled Trial

Authors

  • Lombardi F Department of Gastroenterology, University of Turin, Turin, Italy Author
  • Tamme K Department of Clinical Nutrition, University of Tartu, Tartu, Estonia Author
  • Petraitiene T Department of Microbiology, Lithuanian University of Health Sciences, Kaunas, Lithuania Author

DOI:

https://doi.org/10.5281/zenodo.22343420

Keywords:

chronic idiopathic constipation, flaxseed, psyllium, dietary fibre, gut microbiota

Abstract

Graphical abstract

Background: Chronic idiopathic constipation (CIC) is common and poorly served by fibre monotherapies alone. Objective: To
synthesise published evidence on combined flaxseed-psyllium supplementation for CIC and its effects on gut microbiota.
Methods: Narrative review of published randomised trials, systematic reviews and meta-analyses, and mechanistic studies.
Findings: Flaxseed and psyllium each reliably increase stool frequency and soften consistency; trials combining or directly
comparing them, alongside 16S sequencing studies, show additive laxation and consistent enrichment of
short-chain-fatty-acid-producing taxa. Conclusions: Combined mucilage/gel-forming fibre supplementation is a mechanistically
coherent, evidence-supported first-line strategy for CIC with favourable microbiota effects.

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Graphical abstract

Published

2025-07-28

Issue

Section

Articles

How to Cite

Combined Flaxseed and Psyllium Supplementation Relieves Chronic Idiopathic Constipation and Alters Gut Microbiota Composition in Adults: A Randomized, Double-Blind, Placebo-Controlled Trial. (2025). Journal of Clinical Nutrition and Food Science, 8(1), 41-18. https://doi.org/10.5281/zenodo.22343420