Abstract: SA-PO0889
Effect of Dietary Fiber Based on Fermentability and Viscosity on the Gut Microbiome Composition in Patients with CKD: A Systematic Review of Experimental and Clinical Trials
Session Information
- Health Maintenance, Nutrition, and Metabolism
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Health Maintenance, Nutrition, and Metabolism
- 1500 Health Maintenance, Nutrition, and Metabolism
Authors
- Mirmohammadali, Nooshan, Purdue University, West Lafayette, Indiana, United States
- Carrillo, Claudia A., Iowa State University of Science and Technology, Ames, Iowa, United States
- Reed, Jason, Purdue University, West Lafayette, Indiana, United States
- Hoffman, Hannah W., Indiana University School of Medicine, Indianapolis, Indiana, United States
- Moe, Sharon M., Indiana University School of Medicine, Indianapolis, Indiana, United States
- Biruete, Annabel, Purdue University, West Lafayette, Indiana, United States
Background
Dietary fiber influences the gut microbiome, but effects may vary by fiber properties such as fermentability and viscosity. We systematically evaluated isolated dietary fiber interventions in humans and animals with CKD to determine how these properties affect gut microbiota composition and function in CKD.
Methods
We conducted a systematic review of randomized controlled trials and rodent studies by searching PubMed, Embase, Web of Science, and CENTRAL through 02/06/2026. Eligible studies evaluated gut microbial composition using 16S rRNA sequencing or shotgun metagenomics. Alpha and beta diversity and bacterial taxa were extracted separately for human and animal studies. Due to heterogeneity across studies, results were summarized qualitatively. Risk of bias was assessed using ROB-2 and SYRCLE tools and an overall level of evidence was assigned. Bacterial taxa changes were reported according to these rankings.
Results
Twenty-two studies (9 human, 13 animal) were included, comprising 236 participants and 274 animals with CKD. Dietary fiber supplementation demonstrated limited and inconsistent effects on gut microbiota composition in human studies. Inulin and resistant starch as fermentable non-viscous fibers were associated with weak evidence of changes in beta diversity, but most taxa across phylum and genus levels remained unchanged, often supported by strong or weak evidence depending on the taxonomic level. Modest increases were observed in a small number of genera and phylum, including Verrucomicrobia, Akkermansia, Clostridium by inulin and Oscillospiraceae UCG-002, Subdoligranulum by resistant starch type 2 in human studies, which were not consistent across animal studies. Beta-glucans as a fermentable viscous fiber showed no significant effects on alpha or beta diversity or microbial composition in humans. In contrast, animal studies suggested that beta-glucans may increase alpha diversity, but evidence was weak.
Conclusion
This is the first systematic review in CKD evaluating isolated dietary fiber effects on the gut microbiota. Overall, fiber had minimal impact on microbial composition but evidence (including our own) was associated with changes in microbial metabolites, suggesting benefits are driven by functional rather than compositional changes, with fermentability likely playing a key role.
Funding
- Other NIH Support