Retraction Watch – Paper recommending vitamin D for COVID-19 retracted four years after expression of concern – June 24, 2024 Author Dawn Attride PLOS ONE posted an expression of concern for the article on October 14, 2020. According to the notice, “concerns were raised about the validity of results and conclusions reported in the article and about undisclosed competing interests.” The expression of concern also noted “statements in the article, including in its title and conclusions, that suggest a causal relationship between vitamin D levels and the clinical outcome of COVID-19 infections which is not supported by the data.” The competing interests refer to Holick’s “non-financial interests based on his vitamin D research and other activities focused on vitamin D; contributions to an app that tracks vitamin D; and interests that include consultancies, funding support, and authorship of books related to vitamin D usage.” In 2018, the New York Times reported on Holick’s financial ties to the vitamin D industry.
Vitamin D has been floated as a cure all for all sorts of things for years, without much hard evidence to show for it. But even with that starting point of skepticism, it still took 4 years to retract the paper that already had criticisms out of the gate.
This is demonstrative of why it’s unwise to be using unproven remedies and products with just preliminary findings — especially when those preliminary studies being referenced are years old and haven’t been replicated. I often find people asking about dubious products, and saying “but they linked to this study” with the study either being straight up fraudulent appeal to authority (pointing to a reference that doesn’t actually support the claim), or it’s some tiny preliminary study from a few years ago that hasn’t been replicated. And may well still be retracted for all we know because obviously that can take years. In some cases they point to preprints that are more than a year old and are still yet to be peer reviewed or published, and some doctors are even reportedly prescribing based on such preprints.