ChromaDex review highlights zinc and vitamins B3, C and D in fight against COVID-19

23 Feb 2021 --- Along with an outside consultant, ChromaDex scientists have written a study review arguing that zinc and vitamins B3, C and D hold promise in reducing the risk or severity of COVID-19. However, they acknowledge that firm conclusions await the results of various trials.

“The intent was to provide a high-level review of the literature demonstrating the potential efficacy of nutrient supplements in the treatment or prevention of COVID-19,” study author Dr. Andrew Shao, ChromaDex’s senior vice president of global scientific and regulatory affairs, tells NutritionInsight.

“We limited the scope of the review to essential nutrients – as opposed to the inclusion of a broader range of natural products, such as botanical extracts – since these [essential nutrients] have the most published data demonstrating their important role in immune function.”The researchers emphasize the urgent need to find alternative solutions to decrease the morbidity and mortality of this virus.

Evidence for potentially beneficial roles
The review, published in the Journal of Dietary Supplements, details that as more and more molecular mechanisms involved in SARS-CoV-2 pathogenesis are discovered, additional therapeutic approaches that target disease processes can be tested. 

The researchers point to data supporting that essential nutrients may aid cellular defense and repair mechanisms and thus promote recovery or control of symptoms in late-stage disease.  

They note that zinc and vitamins B3, C and D have been shown in preclinical and some clinical studies to impact the initial innate immune response or modulate subsequent downstream processes related to viral infection.

“The widespread availability of each of the key nutrients discussed here make them easy and, for the most part, safe additions to a healthy diet, lifestyle choices, and behavioral approaches to augmenting the body’s response to and avoiding infection,” the review states. 

The extent to which diet and supplementation can help prevent infection with SARS-CoV-2 or lessen its effects is currently under exploration. There are also many clinical studies underway that are “poised to contribute greatly” to knowledge in this area, the researchers add.

Weighing up the safety
In light of the data, the researchers recommend that consumers be made aware that dietary supplements are regulated by the US Food and Drug Administration (FDA) differently from prescription drugs. 

“The regulatory status of zinc and vitamins B3, C and D in supplements is clear, as these were present in the market well before 1994 and, therefore, have Grandfathered status in supplements,” the review authors state.

However, they emphasize that over-the-counter supplement use should always be discussed with a healthcare provider. 

“Depending on a patient’s underlying health status, supplementation may or may not make sense. For example, some supplemental nutrients can interact with medication. This is something the patient and physician should closely monitor,” says Shao. 

“On the other hand, those with preexisting conditions and at high risk for COVID-19 may also not be nutritionally replete. For example, research shows that people with lower vitamin D status may be at higher risk for COVID-19 and related complications.”

He also notes that zinc and vitamins B3, C and D have wide safety margins and a long history of safe use. However, other supplements like probiotics and botanical extracts can be beneficial but tend to have less research and a shorter history of use.Zinc and vitamins B3, C and D have wide safety margins and a long history of safe use.

Supplement controversy
There has been a great deal of controversy around the usefulness of supplementation during the pandemic. The COVID A to Z trial recently concluded that high doses of zinc gluconate, ascorbic acid or a combination of both nutrients did not significantly shorten the duration of symptoms associated with SARS-CoV-2 compared to usual care.

The Council for Responsible Nutrition (CRN) then dismissed the study as “doing nothing to advance our understanding of the role of nutrients in reducing the risk of COVID-19.”

Another recent study found that vitamin D3 did not reduce the hospital stay of patients with COVID-19.

“These particular studies, as designed (the dose provided, duration, timing, underlying characteristics of the patients), did not demonstrate significant benefit does not change my conclusions, which are based on the totality of available evidence,” Shao says.

He explains that it is possible people need to supplement well in advance and optimize their nutrient status prior to the stress of infection to experience a benefit. Additionally, supplementation after the onset of infection may not confer the same benefit.

“However, we won’t know the answer to that until such a question is actually tested. There are many ongoing studies examining the impact of nutrient supplements on COVID-related outcomes. Hopefully, the results of those will shed additional light on the issue,” Shao concludes.

By Katherine Durrell