Dietary Supplements for COVID-19? Not So Fast

Dietary supplements are not proven to combat COVID-19, new review says

(RxWiki News) Despite what many celebrities and other unproven sources may say, dietary supplements are not a proven way to combat COVID-19.

That's according to a new review that looked at claims surrounding dietary supplements and COVID-19.

The authors of the article also pointed out that pharmacists can play an essential role in fighting potentially harmful misinformation about the coronavirus.

"Pharmacists are an accessible drug information resource who have the ability to provide real-time data-driven education to patients and providers," the authors, of the University of Connecticut, wrote. "News and social media reports should not be the sole source for evidence-based information. During this pandemic when information quickly evolves in the presence of contradicting messages and misinformation, the role of the pharmacist is essential."

This review looked at COVID-19-related claims about several over-the-counter dietary supplements: vitamin C, vitamin D, zinc, elderberry and silver.

Vitamin C

The researchers behind this review wrote that vitamin C does appear to have many beneficial properties, such as reducing free radicals and inflammation. But there isn't enough evidence to support claims that vitamin C can help COVID-19 patients or prevent infection.

Some research, however, does suggest that vitamin C can shorten the length of time that someone has the common cold.

"Whereas the common cold can be caused by a human coronavirus, COVID-19 is caused by a novel coronavirus with a different genome sequence," according to this review. "It cannot be assumed, therefore, that outcomes of vitamin C from the management of the common cold will translate to the management of COVID-19."

Vitamin D

The peak of flu season is at the same time when people get the least sun exposure: the winter. Sun exposure helps the body to create vitamin D, so some have theorized that vitamin D may play a role in immune function.

While some research has supported this idea, and while low vitamin D levels have been tied to respiratory tract infections, there is not enough evidence to suggest that vitamin D can help prevent COVID-19.

"Without studies specific to COVID-19, whether taking daily vitamin D improves outcomes associated with COVID-19 is unknown," these researchers wrote. "For the purpose of overall general health and in the setting of a high prevalence of vitamin D deficiency in America, patients should continue to follow recommendations for daily vitamin D consumption consistent with the recommended daily allowance and tolerable upper intake level."

Zinc

Some scientists have hypothesized that zinc might stop viruses from replicating, and some research has suggested that it may help with the common cold.

Although a doctor in New York is claiming to see a "near perfect clinical response" to a combination of prescriptions that includes zinc, research on this subject is lacking, according to the review.

"Some patients may choose to take zinc during this pandemic, but reputable data are lacking," the authors wrote. "Oral zinc supplementation is likely to be safe up to 40 mg/d in adults, but safety is less certain with greater doses that are implicated in common cold management."

Speak with your doctor before you take zinc or any other supplement.

Elderberry

Some in-depth studies have suggested that elderberry might help shorten the amount of time people with the flu have symptoms. Other research has suggested similar results for the common cold.

But, according to this review, no published studies have looked at elderberry's uses in COVID-19 treatment.

"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," these researchers wrote.

Any part of the raw elderberry plant can be poisonous, and elderberry can also be dangerous for people who have diabetes. Never take this or any other supplement without first speaking with your health care provider.

Silver

Throughout history, some groups have proposed that silver might have antibacterial or antiviral qualities, although these claims were not proven by research. Recently, some popular social media accounts have promoted colloidal silver as a cure for COVID-19. This is an unproven and unsupported claim, according to the researchers who wrote this review.

In fact, since 1999, the US Food and Drug Administration (FDA) has maintained that products that make health claims involving silver are "misbranded."

Exposure to silver can cause permanent skin discoloration, problems with the liver, kidneys and other major organs, neurotoxicity, psychosis and some types of cancer, according to the review.

"Despite the FDA’s warning, colloidal silver is still readily available and advertised to the public," the authors wrote. "Until new evidence supports safety and efficacy, patients should not consume over-the-counter colloidal silver products."

The FDA has warned many companies accused of making unproven claims about products like the ones discussed in this article. There is currently no scientific evidence to support claims involving these products and COVID-19 treatment or prevention.

Talk to your health care provider before starting any new dietary supplement.

This review was published in the Annals of Pharmacotherapy.

The authors disclosed no funding sources or potential conflicts of interest.

Reviewed by: 
Review Date: 
July 1, 2020