Department of Health Sciences, Birmingham City University, Birmingham, UK.
Am J Health Promot. 2025 Jan;39(1):162-171. doi: 10.1177/08901171241273330. Epub 2024 Aug 13.
This systematic review and meta-analysis aimed to evaluate the vitamin B12 status and intake of Seventh-day Adventists following a plant-based diet and compare it with omnivore controls to investigate their susceptibility for vitamin B12 deficiency.
Peer-reviewed articles were identified through a comprehensive search in PubMed, Scopus, and Google Scholar databases from inception up to the year 2024 using specific keywords related to vitamin B12 and Seventh-day Adventists.
Observational studies published in the English language were included if they reported on vitamin B12 status or intake among plant-based Adventists and compared it with omnivore controls who may or may not have been Adventists. Studies that did not present distinguishable results for vegetarian/vegan from omnivore Adventists or only reported on food item intake without specific vitamin B12 data were excluded.
Two independent reviewers extracted data on study characteristics, vitamin B12 intake, and serum levels using a customised data extraction form, resolving discrepancies through consultation with a third reviewer.
A meta-analysis was conducted using random-effect models due to anticipated heterogeneity, without any subgroup analysis due to the low number of studies. Sensitivity analysis was performed using the 'leave-on-out' method to assess individual study influence on overall effect size and heterogeneity.
Four studies met inclusion criteria, encompassing 1994 participants. Meta-analysis showed no significant differences in serum vitamin B12 levels (MD: -9.85 pmol/L; 95% CI: -45.64 to 25.94 pmol/L; = 0.54, I = 50%) or daily intake (MD: 3.31 mcg/d; 95% CI: -4.70 to 11.32 mcg/d; = 0.42, I = 90%) between plant-based Adventists and omnivore controls, although there was high heterogeneity between the studies.
Adventists following a vegan or vegetarian diet did not demonstrate increased risk of vitamin B12 deficiency due to the widespread consumption of fortified foods and supplements. The findings underscore the importance of supplementation and the consumption of fortified foods for maintaining adequate B12 status among vegan or vegetarian Adventists but highlight the need for further studies to confirm these observations in diverse geographical areas.
本系统评价和荟萃分析旨在评估遵循植物性饮食的基督复临安息日会教徒的维生素 B12 状况和摄入量，并将其与杂食对照进行比较，以调查他们对维生素 B12 缺乏的易感性。
通过在 PubMed、Scopus 和 Google Scholar 数据库中使用与维生素 B12 和基督复临安息日会相关的特定关键词，从创建到 2024 年全面搜索，确定了同行评审文章。
如果观察性研究报告了植物性复临信徒的维生素 B12 状况或摄入量，并将其与可能是或可能不是复临信徒的杂食对照进行比较，则纳入本研究。未为素食主义者/素食主义者与杂食性复临信徒提供可区分结果的研究，或仅报告食物摄入而无特定维生素 B12 数据的研究被排除在外。
两名独立审查员使用自定义数据提取表提取研究特征、维生素 B12 摄入量和血清水平的数据，通过与第三名审查员协商解决差异。
由于预期存在异质性，使用随机效应模型进行荟萃分析，由于研究数量较少，因此未进行亚组分析。使用“leave-on-out”方法进行敏感性分析，以评估个别研究对总体效应大小和异质性的影响。
四项研究符合纳入标准，共纳入 1994 名参与者。荟萃分析显示，血清维生素 B12 水平（MD：-9.85 pmol/L；95%CI：-45.64 至 25.94 pmol/L； = 0.54，I = 50%）或每日摄入量（MD：3.31 mcg/d；95%CI：-4.70 至 11.32 mcg/d； = 0.42，I = 90%）在植物性复临信徒和杂食对照之间无显著差异，尽管研究之间存在高度异质性。
由于广泛食用强化食品和补充剂，遵循纯素食或素食饮食的复临信徒并没有增加维生素 B12 缺乏的风险。这些发现强调了补充剂和强化食品的重要性，以维持纯素食或素食复临信徒的充足 B12 状态，但需要进一步研究在不同地理区域证实这些观察结果。
