Summary of COVID-19 vitamin K studies

1. Deschasaux-Tanguy et al., Nutritional risk factors for SARS-CoV-2 infection: a prospective study within the NutriNet-Santé cohort

7,766 patient vitamin K prophylaxis study: 14% fewer cases (p=0.04).
Analysis of 7,766 adults in France, showing higher intakes of vitamin C, folate, vitamin K, dietary fibre, and fruit and vegetables associated with lower seropositivity.
Nov 2021, BMC Medicine, https://link.springer.com/article/10.1186/s12916-021-02168-1/fulltext.html, https://c19p.org/deschasauxtanguyvk

2. Visser et al., Vitamin K2 Supplementation in Hospitalised COVID-19 Patients: A Randomised Controlled Trial

40 patient vitamin K late treatment RCT: 200% higher mortality (p=1), 200% higher ICU admission (p=0.6), and 17% shorter hospitalization (p=0.52).
RCT 40 hospitalized COVID-19 patients showing vitamin K2 supplementation was well-tolerated and reduced dp-ucMGP levels, reflecting improved vitamin K status, but did not affect desmosine, a marker of elastic fiber degradation. The study was not powered to assess effects on clinical outcomes. Authors suggest that the dose may have been insufficient to fully correct the vitamin K deficiency seen in COVID-19, and that higher doses might be required to achieve potential protective effects against inflammation or lung damage.
Jun 2024, J. Clinical Medicine, https://www.mdpi.com/2077-0383/13/12/3476, https://c19p.org/visser