The study:
Kaufman HW, Niles JK, Kroll MH, Bi C, Holick MF. SARS-CoV-2 positivity rates associated with circulating 25-hydroxyvitamin D levels. PLoS One. 2020 Sep 17;15(9):e0239252. doi: 10.1371/journal.pone.0239252. PMID: 32941512; PMCID: PMC7498100. https://pubmed.ncbi.nlm.nih.gov/32941512/
Higher vitamin D levels in the blood were associated with lower levels of COVID-19/SARS-COV-2. See the graphs on the study.
Below, graph of Vit D concentration (X axis) and COVID-19 prevalence.
