The world is now experiencing its third major epidemic of coronavirus (CoV) infections began in Wuhan, Hubei, China, in late 2019 and named COVID-19. After an initial explosive outbreak of pneumonia of unknown etiology in China, the disease spread first to neighboring Asian countries and then worldwide. Patients with COVID-19 presented with a constellation of symptoms such as fever, dry cough, dyspnea, sore throat, and nasal congestion and radiological findings showed bilateral lung glassy opacities. Vitamin D has many mechanisms by which it reduces the risk of microbial infection and death, including physical barrier, cellular natural immunity, and adaptive immunity. Vitamin D supplementation has shown favorable effects in viral infections including influenza and HIV. The effects of vitamin D supplementation during covid 19 infection remain controversial. Looking ahead, clinical studies are needed to define better cut offs for vitamin D levels and, finally, which dosage is the best.
Vitamin D reduces the risk of microbial infection and death.
- Vitamin D supplementation has shown favorable effects in viral infections including influenza and HIV.
- Vitamin D is a negative endocrine renin-angiotensin system (RAS) modulator.
- Vitamin D increases expression and concentration of ACE2 and has a potential protective role against acute lung injury/acute respiratory distress syndrome.
- Despite the potential effectiveness of vitamin D as an antiviral, more solid data are needed to support this claim.