High dose of zinc helps you get over a heavy cold faster
If you're suffering from a heavy cold, zinc lozenges can help you to recover more quickly. In 2011, a researcher at the University of Helsinki discovered this after doing a meta-analysis of previously published trials. There's just one drawback: you have to take high doses of zinc.
Zinc versus colds
Since the 1980s, researchers have conducted several trials in which they studied the effect of zinc supplementation on recovery from the common cold. The outcomes of those studies varied, the results have pointed in all directions.
In 2011 an overview was published of the results from all these studies. [Cochrane Database Syst Rev. 2011 Feb 16;(2):CD001364.] This meta-study concluded that "zinc administered within 24 hours of onset of symptoms reduces the duration and severity of the common cold in healthy people".
Results
The 2011 study looked at all sorts of zinc supplements. The Finnish study, on the other hand, only looked at lozenges. Nutritionists think that the body absorbs the zinc in this kind of tablet better. The study also distinguished between high-dose and less high-dose supplements.
Taking less than 75 mg per day has no effect, as is shown in the table below. Higher doses do have an effect, and reduce the length of the sickness by 42 percent.
In the most effective trial included in the meta-study, the preparation given reduced the length of sickness by 64 percent. The subjects were given 207 mg zinc per day.
Click on the figure and table below for a larger version.
Conclusion
Taking such high doses of zinc for years may not be healthy. According to some epidemiological studies, this may increase the risk of prostate cancer. [J Natl Cancer Inst. 2003 Jul 2;95(13):1004-7.] However, taking a high dose of zinc for a few days is harmless.
Source:
Open Respir Med J. 2011;5:51-8.
