The Influence of the Dietary and Lifestyle Practices of Seventh-Day Adventists on COVID-19 Health Outcomes

Janko, Robert K.

The Influence of the Dietary and Lifestyle Practices of Seventh-Day Adventists on COVID-19 Health Outcomes

Janko, Robert K. (2025) The Influence of the Dietary and Lifestyle Practices of Seventh-Day Adventists on COVID-19 Health Outcomes. Doctoral thesis, Birmingham City University.

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Abstract

This thesis assessed the influence of the dietary practices of Seventh-day Adventists within the context of their lifestyle on COVID-19-related health outcomes such as the incidence of COVID-19 infection, symptom severity and risk of long-COVID.

Therefore, a two-year prospective cohort study involving 170 participants (86 Adventists and 84 non-Adventists) was conducted to compare COVID-19 outcomes among Adventists and non-Adventists. The study showed that Adventists had a significantly lower incidence of COVID-19 infection (OR 0.45, 95% CI 0.2,1.0, p=0.05) and had a significantly reduced risk of experiencing severe symptoms as well as long COVID symptoms. These outcomes were observed despite Adventists being older and having a lower vaccination rate. Logistic regression analysis further revealed that adherence to a plant-based diet was significantly associated with reduced COVID-19 risk. Furthermore, being a vegetarian Adventists was associated with significantly less weight gain during the pandemic compared to non-vegetarians and Adventists overall reported frequent lower levels of pandemic-related stress and less weight gain during the lockdowns, which may have positively influenced their COVID-19 risk significantly.

Plant-based Adventists were shown to consume fewer dietary supplements than omnivores, specifically vitamin B12 and vitamin D; however, this did not correspond to increased COVID-19 risk. A systematic review and meta-analysis supported that vegan and vegetarian Adventists typically met recommended intakes for most nutrients that can influence immunity and thus COVID-19 susceptibility, though potential deficiencies in calcium, zinc and iron were noted. These findings led to the design and implementation of a targeted educational intervention among plant-based Adventists who were living in the UK. The educational intervention identified significant gaps in general and COVID-19 specific nutrition knowledge among the recruited plant-based Adventists at baseline, which was effectively improved by the educational intervention, which showed a large effect size (Hedges' g = −2.681, p < 0.001). The 4-week follow-up questionnaire showed that 49% of participants had begun to use supplements after the intervention and 59% reported using more fortified foods, indicating that the intervention successfully led to behaviour change.

These findings suggest that the Adventist lifestyle, characterized by the widespread consumption of a plant-based diet, regular fasting, abstention from harmful substances such as alcohol and tobacco, maintenance of a healthy bodyweight, and the use of stress management practices such as Bible reading, prayer and singing and the strong social support structure may offer protection against COVID-19 infection. In conclusion, the studies described within this thesis have provided important answers for the association between COVID-19 incidence and Adventist dietary practices and may have implications for health promotion for Adventists living in the UK and worldwide.

Item Type:	Thesis (Doctoral)
Dates:	Date Event 26 September 2025 Accepted
Uncontrolled Keywords:	COVID-19, Adventist, Diet, Lifestyle
Subjects:	CAH02 - subjects allied to medicine > CAH02-05 - medical sciences > CAH02-05-02 - healthcare science (non-specific) CAH06 - agriculture, food and related studies > CAH06-01 - agriculture, food and related studies > CAH06-01-06 - food and beverage studies (non-specific) CAH06 - agriculture, food and related studies > CAH06-01 - agriculture, food and related studies > CAH06-01-07 - food sciences CAH15 - social sciences > CAH15-04 - health and social care > CAH15-04-03 - health studies
Divisions:	Doctoral Research College > Doctoral Theses Collection Life and Health Sciences > Life and Sports Sciences
Depositing User:	Louise Muldowney
Date Deposited:	06 Oct 2025 10:21
Last Modified:	06 Oct 2025 10:21
URI:	https://www.open-access.bcu.ac.uk/id/eprint/16658