Gut health in New Zealand vegans : the relationship between dietary fibre and gastrointestinal symptoms : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutrition and Dietetics, Massey University, Albany, New Zealand
Loading...
Date
2024
DOI
Open Access Location
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Massey University
Rights
The author
Abstract
Background: Dietary guidelines recommend adequate dietary fibre intake to support normal laxation and gastrointestinal (GI) health. However, excess intake of some fibre types may lead to the onset of gaseous GI symptoms. Internationally, many vegans exceed the dietary fibre recommendations; however, no studies have investigated its link to reports of GI symptoms. Meanwhile, the gut health and dietary fibre intake of NZ vegans have not been investigated; thus, research is needed. Aim: To investigate the relationship between dietary fibre intake and gastrointestinal symptoms among NZ Vegans. Methods: As part of the Vegan Health Research Programme, this cross-sectional study recruited adults aged ≥18yrs who had followed a strict vegan diet for at least two years. Health and demographic data were obtained from questionnaires. Participants completed a 4-Day Food Record to investigate dietary fibre intake, which was compared to the NZ median intake and Nutrient Reference Values (NRVs) for the dietary fibre Adequate Intake (AI) and Suggested Dietary Target (SDT) recommendations. A Gastrointestinal Symptom Rating Scale (GSRS) questionnaire was completed by the participants to investigate the prevalence and severity of GI symptoms. A binary logistic regression analysis was conducted to determine whether there was a correlation between GSRS outcomes and dietary fibre intake. Results: Across the GSRS domains, no correlations were found between dietary fibre intake and reports of GI symptoms due to minimal variance in vegans' GSRS scores. Overall, participants (n= 212) reported minimal GI symptoms, ranging on average from ‘no discomfort – minor discomfort’ (GSRS scores 1-2) across the GSRS domains. Females reported worse symptoms of abdominal pain (p=0.02) and indigestion (p<0.001) than males, while younger participants experienced more abdominal pain than older participants (p=0.03), as examined through modelling a binary logistic regression analysis inclusive of dietary fibre intake (g/day), sex, age and BMI. Dietary fibre intake exceeded the NZ median intake (20g/day), averaging 45.91g/day (25th, 75th percentile, 36.33 to 54.75g/day); 97% of participants exceeded the NZ NRV Adequate Intake (AI) (25-30g/day), 90% exceeded the Suggested Dietary Target (SDT) (28-38g/day). While males consumed more dietary fibre than females (52.62g/day versus. 42.24g/day), females had greater energy-adjusted dietary fibre intakes than males (22.21g/1000kcal versus. 20.54g/1000kcal). Finally, the major sources of dietary fibre were legumes, bread, fruit, oats, and vegetables. Conclusion: NZ vegans experience minimal GI symptoms, while their dietary fibre intake exceeds the NZ NRV recommendations and population median intake. Overall, there were no associations between high dietary fibre intake and reports of GI symptoms among NZ vegans.
Description
Keywords
vegans, GI symptoms, dietary fibre, GSRS, gut health