A pooled analysis of the existing data published in the open access journal BMJ Open reveals that taking a zinc supplement can help prevent symptoms of respiratory tract infections like coughing, congestion, and sore throat, as well as shorten the duration of illness.
At the same time, little is known about the ideal way to take zinc for a cold, and whether zinc can help improve COVID-19.
Zinc is important for immune function, inflammation, tissue injury, blood pressure, and tissue responses to oxygen deprivation.
As a result, during the current pandemic, it has sparked substantial interest in the prevention and treatment of COVID-19 infection.
According to the authors, the goal of the new study wasn't to see if zinc could help with colds in general. Their main goal was to see if zinc could help with COVID-19, as the mineral has become a popular home remedy for the viral infection.
Up until August 2020, the review includes 28 clinical trials involving 5446 adults that were published in 17 English and Chinese research databases.
Lozenges were the most commonly used zinc formulation, followed by nasal sprays and gels containing zinc acetate or gluconate salts. Doses differed significantly depending on the formulation and whether zinc was used for prevention or treatment.
Overall, they discovered only minor benefits for zinc when compared to a placebo. They estimated that zinc lozenges or nasal sprays, for example, would prevent five cold cases for every 100 people who used them for a month.
In comparison to placebo, lozenges and nasal sprays were associated with two fewer days of symptoms on average. They also anticipated that if participants took zinc, 19 out of every 100 persons would develop cold symptoms by day seven.
Perhaps most importantly, the researchers discovered no consistent pattern in the data for the best way to take zinc, such as the safest dose, the best route of administration, or whether any other treatments could work in conjunction with zinc to enhance its effects.
Despite the limitations of the data, the researchers believe that zinc is a viable option for preventing and treating the common cold, especially when compared to over-the-counter medications with worse side effects or medicines that will definitely have no effect but are sometimes prescribed to reassure patients, such as antibiotics for a suspected viral infection.
