Determinants of iron status in vegans living in Auckland, New Zealand : 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...
Files
Date
2023
DOI
Open Access Location
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Massey University
Rights
The author
Abstract
Background: A vegan diet has many health benefits; however, certain nutrients are not available in sufficient quantities or are less bioavailable in plant food. One example is iron, presenting a risk for iron deficiency (ID). Research on iron intake and status in vegans is limited and has not been explored in a NZ vegan sample population. Objectives: To investigate iron intake and status in a NZ vegan sample population. As well as exploring risk for ID and potential risk factors for iron depletion in this sample population. Methods: Vegans living in Auckland, NZ were recruited. Nutrient intake was gathered through participant-completed four-day food records (4D-FR). Biomarkers of iron status were measured including Serum ferritin (SF), haemoglobin (Hb), serum iron, iron-binding capacity (TIBC) and transferrin saturation (TSAT). Health, demographic and lifestyle factors were assessed through questionnaires. Participants were grouped as ID (SF <30µg/L) and iron sufficient (SF ≥30µg/L) and the differences between groups were assessed. Results: Vegan males and females (n=212) aged 19-75 years participated. Mean iron intake was above estimated average requirements (EAR) and recommended dietary intake (RDI) for males and above EAR for females. The prevalence of ID was 47.3% overall. Significantly higher rates of ID were found in females (F) (58.7%) compared to males (M) (15.4%) (p≤0.001). In all participants, being female (p≤0.001), younger age (p≤0.001), a previous diagnosis of iron deficiency (p≤0.001), and blood donation within the last six months (p=0.004) were potential risk factors of ID. In females, being younger (p≤0.001), blood donation within the last six months (p=0.025), and still menstruating (p=0.010) were significant potential risk factors of ID. In males, energy (p≤0.001), protein (p=0.004), dietary fibre (p≤0.001), iron (p=0.001), calcium (p=0.003) and vitamin C (p=0.006) intake was significantly higher in ID (n=6) compared with iron sufficient (n=41) males. No significant differences in dietary intake were observed between ID and iron sufficient females. Conclusion: Nearly half of the vegan sample was ID, with over half of vegan females ID. Iron deficiency was most prevalent in females, younger individuals, those previously diagnosed with ID and those that had donated blood within the last six months. Dietary intake was only found to be associated with ID in males and not females. This study has provided novel insights on the risk of ID for vegans living in New Zealand.