Zinc supplements may help prevent respiratory infections such as colds, flu, and COVID-19

However, the quality of the evidence varies and the optimal formulation and dosage is not clear.

Zinc supplements may help stop symptoms of respiratory tract infections such as cough, congestion, sore throat and shorten the duration of the illness, and a pooled analysis of available evidence published in the Open Access Journal Suggests BMJ Open..

However, the quality of the evidence on which these findings are based varies, and it is not clear what the optimal prescription or dosage of this nutrient is, warn researchers.

Airway infections include colds, flu, sinusitis, pneumonia, and COVID-19 (New Coronavirus Infection).. Most infections heal spontaneously, but not all. It is also often costly in terms of impact on medical services and the time it takes to take sick leave.

Zinc plays an important role in tissue response to immunity, inflammation, tissue damage, blood pressure, and lack of oxygen.

As a result, there has been considerable interest during the current pandemic on the potential for prevention and treatment of COVID-19 infection.

In response to a request for rapid evidence assessment to inform self-care and clinical practice, researchers evaluated zinc prevention and treatment. SARS-CoV-2, The virus that causes COVID-19, and other viral respiratory tract infections.

The results of some relevant clinical trials were not yet available when the review was published, so this current review updates the available evidence.

This review includes 28 clinical trials of 5446 adults published in 17 English and Chinese research databases by August 2020. No studies have specifically investigated the use of zinc for the prevention or treatment of COVID-19.

The most common zinc formulation used was a troche followed by a nasal spray and a gel containing either zinc acetate or gluconate. Dosages varied significantly depending on the formulation and whether zinc was used for prophylaxis or treatment.

A pooled analysis of the results of 25 trials showed that zinc lozenges or nasal drops prevented 5 respiratory tract infections in 100 people per month compared to dummy treatment (placebo).

These effects were most powerful in reducing the risk of developing more serious symptoms such as fever and flu-like illness. However, this is based on only three studies.

On average, symptoms resolved 2 days before using either zinc spray or a liquid formulation taken sublingually (sublingually) than with placebo.

In the first week of illness, participants who used sublingual or nasal spray zinc could recover almost twice as much as those who used placebo. Without zinc, 19 out of 100 adults could show symptoms even after a week. supplement.

Zinc was not associated with relief of mean daily symptom severity, but was associated with a clinically significant reduction in symptom severity on day 3.

Side effects such as nausea and mouth / nasal inflammation could be about 40% higher among people using zinc, but 25 trials that monitored them did not report any serious side effects. Hmm.

However, compared to placebo, sublingual zinc did not reduce the risk of developing infections or cold symptoms after inoculation with hitrinovirus. Also, there was no difference in the duration of illness between those who took zinc supplements and those who did not.

Also, the comparative effect of different zinc preparations and doses was not clear. Also, the quality, size, and design of the studies included were quite different.

“The slight benefits of other over-the-counter and prescription drugs, strain specificity, drug resistance, and potential risk make zinc a viable” natural “alternative to non-specific self-management. [respiratory tract infections], The researcher writes.

“”[Zinc] It also provides clinicians with management options for patients who may be anxious for faster recovery times and may be seeking unnecessary antibiotic prescriptions, “they add.

“But clinicians and consumers are quite concerned about the clinical efficacy of various zinc preparations, doses, routes of administration, and the extent to which their efficacy can be affected by the ever-changing epidemiology of the causative virus. It should be noted that the uncertainty remains. [respiratory tract infections]”They warn.

They conclude that further research is needed to determine how accurately zinc is effective in treating respiratory infections, including COVID-19.

Reference: “Zinc for the Prevention or Treatment of Acute Viral Respiratory Infections in Adults: Rapid Systematic Review and Meta-Analysis of Randomized Controlled Trials,” November 1, 2021 BMJ Open..
DOI: 10.1136 / bmjopen-2020-047474