There is a lack of evidence supporting the use of dietary supplements for the prevention or treatment of coronavirus disease 2019 (COVID-19), despite what recent news or social media platforms have asserted, according to a recent review published in Annals of Pharmacotherapy.
According to the authors, a number of medical entertainment personalities have advocated that specific dietary supplements may prevent or treat COVID-19, leading to large increases in sales of these supplements. “Here, we review select supplements that have been most frequently touted within social media and news outlets for COVID-19 prevention and/or treatment, including vitamin C, vitamin D, zinc, elderberry, and silver,” the study authors explained.
Findings of the review determined that, overall, there is a dearth of evidence supporting the safety and efficacy of these supplements for the prevention or treatment of COVID-19. Despite the theoretical benefits of its use in viral infections, there is a lack of evidence indicating vitamin C effectively prevents or treats COVID-19. Recently, various media outlets in China have stated that large doses of intravenous (IV) vitamin C effectively reduce mean hospital length of stay in patients with moderate to severe COVID-19, however, these findings have not been published at this time.
As for vitamin D, both the former director of the Centers for Disease Control and Prevention (CDC) as well as faculty from the University of Turin in Italy have suggested that maintaining adequate levels may play a role in the management of COVID-19. The report from Italy additionally stated that IV calcitriol may be effective for COVID-19 patients with compromised respiratory function and suggested that a “very high prevalence of hypovitaminosis D” was observed in COVID-19 patients.
Despite these reports, no specific studies assessing vitamin D in the prevention or management of COVID-19 have been performed. As such, patients are recommended to continue to follow daily vitamin D consumption recommendations until scientific evidence proving its safety and efficacy in the setting of COVID-19 emerges.
Although reports regarding the use of zinc for the management of COVID-19 are beginning to emerge, no studies evaluating its safety and efficacy in the setting of COVID-19 have been published. A New York physician stated that the combination of hydroxychloroquine, azithromycin, and zinc is effective, however, no data have been published to support this claim. At this time, a small number of clinical trials have been registered to evaluate zinc as a part of a regimen for the treatment of COVID-19.
“Although there exists a hypothetical benefit of elderberry for the treatment of viral infections, conclusive evidence from high-quality clinical trials is lacking, and data addressing elderberry’s role with COVID-19 are absent,” the authors stated. Elderberry is considered safe when cooked and used in moderation, however, it should be used cautiously due to its extensive adverse effect profile as well as its potential to interact with other drugs and comorbid conditions.
During the pandemic, silver toothpaste and silver solution were promoted as potential treatments for COVID-19 by several social media personalities. Colloidal silver has been readily available during this time, despite the Food and Drug Administration (FDA) declaring over-the-counter products containing silver were not considered safe or effective in 1999. Due to the potential for harmful adverse effects, including neurotoxicity, patients should avoid colloidal silver products until evidence supporting use is published.
“Patients and providers should not rely on dietary supplements to prevent or cure COVID-19,” the authors concluded. They added, “Pharmacists have the responsibility to ensure that patients have accurate information regarding the current lack of data supporting efficacy of these supplements in COVID-19.”
Adams KK, Baker WL, Sobieraj DM. Myth Busters: Dietary Supplements and COVID-19 [published online May 12, 2020]. Annals of Pharmacotherapy. doi: 10.1177/1060028020928052.