Abstract
Background: High dietary fibre (DF) intake may have beneficial effects on gastrointestinal and brain interactions. Bread is an ideal vehicle to incorporate grain fibre to increase DF content. To date, no studies have explored the association between a habitual intake of bread fortified with unique grain fibre and gastrointestinal symptoms, general wellbeing, and mental health. Objective: To determine whether a four-week intake of bread fortified with unique grain fibre (thrice the amount of DF than control bread) improves subjective gastrointestinal symptoms, general wellbeing, and mental health compared to baseline and white toast (control bread) in healthy adults with low DF intake. Methods: A four-week, two-armed, placebo-controlled, double-blinded, randomised crossover study separated by a two-week washout period was conducted. Fifty-six participants with low DF intake (<18 g/day for females, <22 g/day for males) consumed three (females)/four (males) slices of fortified bread daily for four weeks then control bread and vice versa. Before and after each intervention phase, the participants completed seven self-reported questionnaires: the Gastrointestinal Symptom Rating Scale, Patient-Reported Outcome Measurement Information System-Anxiety and Depression Short Forms 8a, World Health Organisation Well-Being Index, Warwick-Edinburgh Mental Wellbeing Scales, Multidimensional Fatigue Inventory Short Form, and the Subjective Vitality Scale. Results: Fifty-five participants completed all of the questionnaires before and after each intervention. The preliminary and blinded results showed no significant changes (all p > 0.05) in gastrointestinal symptoms, general wellbeing, and mental health following intervention and between interventions. Discussion: With thrice the amount of DF, the unique grain fibre-fortified bread did not cause gastrointestinal symptoms nor did it worsen general wellbeing and mental health in healthy adults with low DF intake. Encouraging the consumption of unique grain fibre-fortified bread could still be an acceptable and effective method to improve DF intake in a healthy adult population with low DF intake. Trial Registration: ACTRN12622000884707.
Author Contributions
Conceptualization, R.B.G. and N.C.R.; methodology, R.B.G. and N.C.R.; validation, R.B.G., N.C.R., C.L.W. and S.B.B.; formal analysis, H.M.N., J.M; investigation, H.M.N., J.M., C.L.W., S.B.B., R.B.G. and N.C.R.; data curation, H.M.N., J.M.; writing—original draft preparation, H.M.N.; writing—review and editing, H.M.N., J.M., C.L.W., S.B.B., R.B.G. and N.C.R.; supervision, C.L.W., S.B.B., R.B.G. and N.C.R.; project administration, S.B.B.; funding acquisition, N.C.R. All authors have read and agreed to the published version of the manuscript.
Funding
The study was mainly funded by the High-Value Nutrition National Science Challenge, which was funded by the New Zealand Ministry of Business, Innovation and Employment (MBIE), contract number (UOAX1902). Goodman Fielder provided approximately 10 percent of cash co-funding and in-kind contributions.
Institutional Review Board Statement
The study was carried out in accordance with the International Conference of Harmonization Guidelines, national and local requirements, and the Declaration of Helsinki. Ethical approval was sought from the University of Otago Human Ethics Committee for Health (H22/061) and approval was also sought from the University of Otago Christchurch Māori Research Advisor. Prior to commencement, the study was registered at ANZCTR, registration number ACTRN12622000884707.
Informed Consent Statement
Informed consent was obtained from all subjects involved in the study. Written informed consent has been obtained from the patient(s) to publish this paper.
Data Availability Statement
Dataset available on request from the authors.
Conflicts of Interest
The authors declare no conflict of interest.
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. |
© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).