Singh, M., Das, R.R. Zinc for the common cold. Cochrane Database Syst Rev. 2011 Feb 16;(2):CD001364. doi: 10.1002/14651858.CD001364.pub3
1) The common cold is one of the most common causes for illness, doctor visits, and missing school/work. The average child gets eight colds per year and the average adult gets three colds per year. This study proposed assessing zinc supplementation as beneficial for the common cold. This was a Cochrane review that included randomized, double-blind placebo-controlled trials with zinc; both the treatment and prevention of colds were assessed. Nine hundred sixty-six participants in 13 trials were assessed and findings showed that there was a significant reduction in the duration and severity of the colds with zinc. In two preventative trials with 394 participants, there was decreased incidence of colds, less antibiotic use, and fewer school absences in the zinc group. However, there was also a higher rate of nausea and bad taste in the zinc group. Results showed that zinc should be administered within one day of symptoms at the onset of the cold to be effective and should continue for at least five days.
2) The patients were randomized and they only included placebo-controlled trials. This review used a total of 15 different studies that were very heterogeneous in the outcomes they measured and the type and amount of zinc that was used. They included the best studies available to date with the best methodology, but given the variety in studies, it is hard to make clear statements on exact recommendations. Patients may have also known what group they were in based solely on the taste of zinc and nausea associated with its use. Treatment effects were clearly shown in some studies and not clear in others. However, overall the results showed that if zinc is taken within one day of symptoms, the patient had a two-day earlier resolution of their cold as well as decreased severity. The patients in these studies tended to be outpatients and not ED patients. Given that side effects are minimal and not life threatening, the benefits are worth the potential risk.
3) Although this is not a lifesaving treatment, it is something that is safe and can provide patients with an additional way to fight off viral infections in lieu of only purchasing over- the-counter cold relievers. It has also been shown that patients who take zinc end up being prescribed fewer antibiotics, which is highly beneficial to both patients and healthcare at the national level.
Coben Thorn
