Series on COVID Therapy Studies – Considering Zinc
With the onslaught by COVID and its coinciding onslaught of self-proclaimed excerpts with every opinion under the sun, I choose to respond with a series of research study reports so you can choose for yourself. Each edition will offer a number of studies describing possible therapies for COVID (or other coronaviruses) under investigation or reported in past research. As my recent Facebook Live video noted, we do not know enough about this virus to be definite at this time. I am not claiming any of these are the preventive or curative answers for you or your family’s safety. I just want you to be aware of these studies and have knowledge so that you can grow in wisdom rather than stumble about in panic.
Zinc offers a long history of scientific research as an antiviral therapy. This history varies from promising to disappointing not only for more common viruses but also for COVID. Multiple immune and viral mechanisms are known to be influenced by zinc (A). Its potential was sufficient that the Cochrane Review looked at it but due to possible plagiarism (B), their review was removed from their site. The prior publication which is reportedly plagiarized did report that higher doses of zinc were beneficial in regards to the common cold (C).
As a supplement information resource, Consumer Labs (subscription required) listed Zinc at the top of their possibly effective natural therapies list for coronavirus. They based this on a study in PLoS Pathogens (D). This study demonstrated inhibition of Coronavirus RNA polymerase in vitro (the enzyme allowing the virus to multiply) and a blocking of viral replication in cell culture. More study is needed before saying that zinc therapy or exactly how much zinc would help COVID.
Prior studies like one in Advances in Nutrition (E) from 2019 note that zinc deficiency appears to increase the risk of viral illnesses. They also point out the increased occurrence of zinc deficiency in many countries. From their list of references, several studies supporting zinc use in the common cold are provided further below (F). One study did not show any benefit (G). Another analysis in Clinical Infectious Disease from 2007 (H) did not believe the evidence supported its use.
If you are interested in other overviews with further rabbit trails to consider, the Journal of Evidence-based Complementary & Alternative Medicine and the Alternative Medicine Review provide reviews of various therapies including zinc.
In summary, we can go as far as saying the following: zinc plays an important role in immunity, zinc deficiency increases susceptibility to infection, zinc may help with the common cold, and zinc at the right doses may protect against COVID. As with just about all aspects of COVID, we cannot be more definite than this. Use discernment in determining if you use zinc for prevention or as therapy. Like nearly all therapies, natural and synthetic, you can get too much of a good thing. There have been reports of zinc interfering with the sense of smell. Any vitamin or mineral has the potential for overdose just like pharmaceuticals. Use discernment and don’t overdo it.
Prasad A. S. (2008). Zinc in human health: effect of zinc on immune cells. Molecular medicine (Cambridge, Mass.), 14(5-6), 353–357. https://doi.org/10.2119/2008-00033.Prasad
Hemilä H. (2011). Zinc lozenges may shorten the duration of colds: a systematic review. The open respiratory medicine journal, 5, 51–58. https://doi.org/10.2174/1874306401105010051
(D) te Velthuis, A. J., van den Worm, S. H., Sims, A. C., Baric, R. S., Snijder, E. J., & van Hemert, M. J. (2010). Zn(2+) inhibits coronavirus and arterivirus RNA polymerase activity in vitro and zinc ionophores block the replication of these viruses in cell culture. PLoS pathogens, 6(11), e1001176. https://doi.org/10.1371/journal.ppat.1001176
Eby, G. A., Davis, D. R., & Halcomb, W. W. (1984). Reduction in duration of common colds by zinc gluconate lozenges in a double-blind study. Antimicrobial agents and chemotherapy, 25(1), 20–24. https://doi.org/10.1128/aac.25.1.20
Zinc Gluconate and the Common Cold: A Controlled Clinical Study. J C Godfrey, B Conant Sloane, D S Smith, …First Published June 1, 1992 Research Article Find in PubMed https://doi.org/10.1177/030006059202000305
Mossad SB, Macknin ML, Mendendorp SV, et al. Zinc Gluconate Lozenges for Treating the Common Cold: A Randomized, Double-Blind, Placebo-Controlled Study. Ann Intern Med. 1996;125:81–88. doi: https://doi.org/10.7326/0003-4819-125-2-199607150-00001
Randomized, double-masked, placebo-controlled clinical study of the effectiveness of zinc acetate lozenges on common cold symptoms in allergy-tested subjects. Author links open overlay panelEdward J.Petrus, Kenneth .Lawson, Luke R.Bucc,i Kenneth Blum, https://doi.org/10.1016/S0011-393X(98)85058-3
Ann Intern Med. 2000 Aug 15;133(4):245-52. Duration of symptoms and plasma cytokine levels in patients with the common cold treated with zinc acetate. A randomized, double-blind, placebo-controlled trial. Prasad AS(1), Fitzgerald JT, Bao B, Beck FW, Chandrasekar PH.
Turner, R. B. and W. E. Cetnarowski (2000). “Effect of treatment with zinc gluconate or zinc acetate on experimental and natural colds.” Clin Infect Dis 31(5): 1202-1208.
Clin Infect Dis. 2007 Sep 1;45(5):569-74. Epub 2007 Jul 20. Treatment of naturally acquired common colds with zinc: a structured review. Caruso TJ(1), Prober CG, Gwaltney JM Jr.
Mousa H. A. (2017). Prevention and Treatment of Influenza, Influenza-Like Illness, and Common Cold by Herbal, Complementary, and Natural Therapies. Journal of evidence-based complementary & alternative medicine, 22(1), 166–174. https://doi.org/10.1177/2156587216641831
Altern Med Rev. 2007 Mar;12(1):25-48. Colds and influenza: a review of diagnosis and conventional, botanical, and nutritional considerations. Roxas M(1), Jurenka J.
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