The role of zinc in managing viral infections, particularly those caused by coronaviruses, has been a subject of ongoing investigation. While zinc is known to be important for immune function, the evidence regarding its effectiveness against COVID-19 remains limited and nuanced.
Zinc and the Immune System
Zinc is an essential mineral with well-established roles in immune cell development and function. It’s known to support the body’s defense against pathogens. Research has demonstrated that zinc possesses antiviral properties, and it has been shown to shorten the duration of the common cold in some studies. This is thought to be due to zinc’s ability to interfere with viral replication.
Early Research and the Common Cold
A meta-analysis of seven randomized controlled trials indicated that zinc lozenges could shorten the mean duration of the common cold by approximately 33% (95% confidence interval: 21%–45%). This finding sparked interest in exploring zinc’s potential role in combating other coronavirus infections, including COVID-19.
COVID-19 and Zinc: What the Research Shows
Initial investigations into zinc’s impact on COVID-19 focused on its potential to interfere with the virus’s replication process. Studies suggested that zinc might slow the ability of viruses to make copies of themselves within the body. Specifically, research indicated zinc could interfere with proteolytic processing of polyproteins in RNA viruses and the RNA polymerase of SARS-CoV-1.
A retrospective review of 28 consecutive patients with outpatient COVID-19, conducted in , explored the effects of zinc treatment. While this study offered preliminary insights, larger, more robust studies were needed to confirm these findings.
Some observational data suggested that hospitalized COVID-19 patients taking supplemental zinc alongside standard therapy experienced lower death rates. Patients with lower zinc levels upon admission to the hospital appeared to have higher mortality rates. However, these associations do not prove causation, and further research is necessary to understand the relationship between zinc levels and COVID-19 outcomes.
Current Understanding and Limitations
As of , scientists acknowledge that while zinc plays a role in supporting the immune system and may help with the common cold, there is no conclusive evidence demonstrating that taking zinc will prevent someone from contracting COVID-19 or significantly ease its symptoms. The novel coronavirus responsible for COVID-19 is distinct from the coronaviruses that typically cause the common cold.
Studies examining the effects of zinc on SARS-CoV, a coronavirus closely related to the one causing COVID-19, showed that zinc slowed the virus-copying process. However, these studies were conducted in laboratory settings, using cells, rather than with people taking zinc supplements. This limits the applicability of these findings to real-world clinical scenarios.
Important Considerations and Cautions
It’s crucial to understand that zinc alone cannot prevent or cure a COVID-19 infection. Public health officials continue to emphasize that vaccination, staying up-to-date with boosters, minimizing exposure in poorly ventilated indoor spaces, and avoiding crowded locations remain the most effective strategies for preventing COVID-19.
If an individual contracts COVID-19, zinc is not considered a curative treatment. Any potential benefit of zinc in alleviating COVID-19 symptoms is likely to be small. There is also no evidence to support claims that zinc or other dietary supplements can “boost” or “supercharge” the immune system to provide protection against infections.
The U.S. Food and Drug Administration (FDA) is actively investigating fraudulent products marketed as COVID-19 cures, highlighting the importance of relying on credible sources of information and avoiding unverified claims.
The Bottom Line
While zinc is an essential nutrient with a role in immune function, the current body of evidence does not support its widespread use as a preventative measure or treatment for COVID-19. Further research is needed to fully elucidate the potential benefits and risks of zinc supplementation in the context of coronavirus infections. Individuals should continue to follow public health guidelines and consult with their healthcare providers for personalized medical advice.
