Hey, I'm an MD at Iodine. Basically, zinc works. A Cochrane meta-analysis from 2013 showed that zinc lozenges reduce the severity and duration of common cold symptoms. It’s the closest thing we have yet to a cure for the common cold. Get the lozenges in particular (other forms don’t seem to work as well), and take ‘em on a full stomach or you can get really nauseated.
I'm actually curious about this too - I've had pretty great success with zinc lozenges, but was off-put by this. Although the study is for some very specific intranasal products from a specific brand, I think.
I only have anecdotal data to add, but I've been using zinc lozenges for years for when I start to get sick (or my kids are exhibiting symptoms), and it really does dramatically shorten the cold and reduce the severity of the symptoms.
Are you aware of any information on the mechanism by which zinc works? I'm content knowing that it does, but it would be cool to understand what's going on with it.
Zinc is essential for all sorts of human biological processes, including DNA transcription, DNA repair, and antioxidant defence. [1] Since most immune cells are don't live very long[2] one theory goes optimum zinc intake improves all cell reproduction but especially fast turnover cells.
I've been using zinc for about 3 years now when I get a cold. It's the best medication I've found. It has a slightly off-putting taste and mouthfeel, but it's worth it IMO.
http://summaries.cochrane.org/CD001364/ARI_zinc-for-the-comm...