Effects of defatted rice bran-fortified bread on gut microbiome, cardiovascular risk, gut discomfort, wellbeing and gut physiology in healthy adults with low dietary fibre intake

Simple item page
dc.citation.volume67
dc.contributor.authorNg HM
dc.contributor.authorMaggo J
dc.contributor.authorWall CL
dc.contributor.authorBayer SB
dc.contributor.authorMullaney JA
dc.contributor.authorCabrera D
dc.contributor.authorFraser K
dc.contributor.authorCooney JM
dc.contributor.authorGünther CS
dc.contributor.authorMcNabb WC
dc.contributor.authorFoster M
dc.contributor.authorFrampton C
dc.contributor.authorGearry RB
dc.contributor.authorRoy NC
dc.date.accessioned2025-04-15T03:20:28Z
dc.date.available2025-04-15T03:20:28Z
dc.date.issued2025-06
dc.description.abstractBackground & aims: Inadequate dietary fibre (DF) intake is associated with suboptimal gut function and increased risk of several human diseases. Bread is commonly consumed and is ideal to incorporate cereal bran to increase DF content. No human studies have investigated the effects of defatted rice bran (DRB) in bread, which has triple the DF of white bread, purported hypo-allergenicity and a unique nutrient profile, as a dietary intervention in healthy adults. This study aims to assess the relative abundances of a composite of key faecal microbial genera and species involved in DF fermentation and metabolism following the habitual intake of DRB-fortified bread and its influence on other biological markers of host and microbial interactions, cardiovascular risk profile, patient-reported outcomes, total DF intake, and gut physiology in healthy adults with low baseline DF intake. Methods: Fifty-six healthy adults with low baseline DF intake (<18 g/day (females), <22 g/day (males)) completed a two-arm, placebo-controlled, double-blind, randomised, crossover study. Participants consumed three (females) or four (males) slices of DRB-fortified bread or control bread daily as part of their usual diet for four weeks, with the intervention periods separated by a two-week washout. Outcomes included faecal microbiota composite (primary outcome); relative abundances (taxa and gene); faecal moisture content and bile acid concentrations; plasma and faecal organic acid concentrations; cardiovascular risk profile; gut comfort, psychological wellbeing parameters; total DF intake; whole gut transit time, and were measured at baseline and following each intervention phase. Additionally, in a sub-study, 15 participants ingested gas-sensing capsules to assess whole and regional gut transit times, and total and regional colonic hydrogen and carbon dioxide concentrations at the same timepoints. Results: DRB-fortified bread consumption significantly increased total DF intake from 20.7 g/day to 43.4 g/day (p < 0.001). No significant differences were observed in the primary outcome, microbial taxa composite within and between groups (False Discovery Rate (FDR) correction, p > 0.10). As compared to control, the DRB group had increased relative abundances of Faecalibacterium prausnitzii (unadjusted p = 0.04), Bifidobacterium longum (unadjusted p = 0.12), and Bacteroides ovatus (unadjusted p = 0.10); lower relative abundances in Coprococcus genus (unadjusted p = 0.09), Roseburia faecis (unadjusted p = 0.02) and Prevotella copri species (unadjusted p = 0.05). However, no significant differences were observed in the relative abundances of these taxa within and between groups (FDR correction p > 0.10) and for most of the other outcomes between groups (p > 0.05). Only mean serum high-density lipoprotein (HDL) concentrations significantly increased (p = 0.006), and mean total cholesterol (TC) to HDL concentration ratio significantly lowered (p = 0.02) in the DRB group compared to the control group. Conclusion: This is the first human study to show that a high-DF DRB-fortified bread improved DF intake, HDL cholesterol profiles, and may affect the gut microbiota composition in healthy adults with low DF intake. These findings support the substitution of white bread with DRB-fortified bread as an effective method to improve DF intake, which may have subsequent benefits on gut physiology and metabolic health.
dc.description.confidentialfalse
dc.edition.editionJune 2025
dc.format.pagination362-376
dc.identifier.citationNg HM, Maggo J, Wall CL, Bayer SB, Mullaney JA, Cabrera D, Fraser K, Cooney JM, Günther CS, McNabb WC, Foster M, Frampton C, Gearry RB, Roy NC. (2025). Effects of defatted rice bran-fortified bread on gut microbiome, cardiovascular risk, gut discomfort, wellbeing and gut physiology in healthy adults with low dietary fibre intake. Clinical Nutrition ESPEN. 67. (pp. 362-376).
dc.identifier.doi10.1016/j.clnesp.2025.03.045
dc.identifier.eissn2405-4577
dc.identifier.elements-typejournal-article
dc.identifier.piiS2405457725001366
dc.identifier.urihttps://mro.massey.ac.nz/handle/10179/72785
dc.languageEnglish
dc.publisherElsevier Ltd on behalf of the European Society for Clinical Nutrition and Metabolism
dc.publisher.urihttps://www.sciencedirect.com/science/article/pii/S2405457725001366
dc.relation.isPartOfClinical Nutrition ESPEN
dc.rights(c) 2025 The Author/s
dc.rightsCC BY 4.0
dc.rights.urihttps://creativecommons.org/licenses/by/4.0/
dc.subjectDietary intervention
dc.subjectFermentation
dc.subjectMicrobial diversity
dc.subjectCardiometabolic health
dc.subjectGut function
dc.subjectFibre metabolism
dc.titleEffects of defatted rice bran-fortified bread on gut microbiome, cardiovascular risk, gut discomfort, wellbeing and gut physiology in healthy adults with low dietary fibre intake
dc.typeJournal article
pubs.elements-id500344
pubs.organisational-groupOther
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
500344 PDF.pdf
Size:
960.23 KB
Format:
Adobe Portable Document Format
Description:
Published version.pdf
Download
License bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
license.txt
Size:
9.22 KB
Format:
Plain Text
Description:
Download
Collections
Journal Articles