Abstract: F1000Research 2022, 11:639 Last updated: 06 JUL 2022 RESEARCH ARTICLE Effect of natural products use prior to infection with COVID-19 on disease severity and hospitalization: A self-reported crosssectional survey study [version 1; peer review: 2 approved with reservations] Refat M. Nimer , Omar F. Khabour , Samer F. Swedan, Hassan M. Kofahi Department of Medical Laboratory Sciences, Jordan University of Science and Technology, Irbid, 22110, Jordan v1 First published: 10 Jun 2022, 11:639 https://doi.org/10.12688/f1000research.121933.1 Latest published: 10 Jun 2022, 11:639 https://doi.org/10.12688/f1000research.121933.1 Abstract Background: Managing coronavirus disease 2019 (COVID-19) using available resources is essential to reduce the health burden of disease. The severity of COVID-19 is affected by nutritional status. In this study the effect of natural product use prior to infection with COVID-19 on disease severity and hospitalization was explored. Methods: This was a cross-sectional study. Between March and July 2021, a self-administered survey was conducted in Jordan. Individuals who recovered from COVID-19 and were ≥18 years old were the study population. Study measures included the use of natural products, COVID-19 severity, and hospitalization status. A multivariate regression model was used for statistical analysis. Results: The mean age (mean ± SD) of the study sample (n=2,148) was 40.25 ± 15.58 years old. Multivariate logistic regression showed that the regular intake of carnation (OR [0.56], CI [0.37–0.85]), onion (OR [0.69], CI [0.52–0.92]), lemon (OR [0.68], CI [0.51–0.90]), and citrus fruits (OR [0.66], CI [0.50–0.89]) before infection were associated with a substantial reduction in COVID-19 severity (P<0.01). Also, the consumption of carnation (OR [0.55], CI [0.34–0.88]), lemon (OR [0.57], CI [0.42–0.78]), and citrus fruits (OR [0.61], CI [0.44–0.84]) were associated with a significant decrease in the frequency of COVID-19induced hospitalization (P<0.01). Conclusions: Regular consumption of carnation, lemon, and citrus fruits before infection was associated with better outcomes for COVID-19. Studies on other populations are required to confirm these findings. Open Peer Review Approval Status version 1 10 Jun 2022 1 2 view view 1. Fatin Y. Atrooz, University of Houston, Houston, USA 2. Caterina Vicidomini, Istituto di Biostrutture e Bioimmagini IBB-CNR, Naples, Italy Any reports and responses or comments on the article can be found at the end of the article. Keywords COVID-19, natural products, carnation, onion, lemon, citrus, hospitalization, severity Page 1 of 16 F1000Research 2022, 11:639 Last updated: 06 JUL 2022 This article is included in the Emerging Diseases and Outbreaks gateway. This article is included in the Coronavirus collection. Corresponding author: Refat M. Nimer (rmnimer@just.edu.jo) Author roles: Nimer RM: Conceptualization, Funding Acquisition, Supervision, Writing – Original Draft Preparation; Khabour OF: Conceptualization, Validation, Writing – Review & Editing; Swedan SF: Data Curation, Formal Analysis, Validation, Writing – Review & Editing; Kofahi HM: Data Curation, Formal Analysis, Methodology, Validation, Writing – Review & Editing Competing interests: No competing interests were disclosed. Grant information: This work was supported by the Deanship of Research, Jordan University of Science and Technology (Grant number 20210173; to Dr. Refat Nimer). The funders had no role in..