A study using active forms of vitamin D3 has shown that the vitamin’s metabolites can inhibit replication and expansion of SARS-CoV-2, the virus that causes COVID-19.

Summarized by Newswise, “researchers on this study say their findings help explain a possible mechanism for why low vitamin D levels seem to promote COVID-19 infection and poor outcome in certain individuals. This correlates to other studies showing a relationship between vitamin D deficiency and poor disease outcomes. More studies and clinical trials are planned to test the efficacy of vitamin D and lumisterol as an antiviral therapeutic for COVID-19 in animals and humans.”

Study authors commented, “Active forms of vitamin D and lumisterol can inhibit SARS-CoV-2 replication machinery enzymes, which indicates that novel vitamin D and lumisterol metabolites are candidates for antiviral drug research.”

In September 2020, Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said he believed that vitamin D could help fight COVID, although he didn’t elaborate at the time on how he knew that to be true.