Cold hard evidence for zinc remedy? Not quite

A new study from the medical clearinghouse Cochrane Database indicates that zinc-containing medications may shed days off cold symptoms compared to a placebo, but the jury is still out on the best formulation recommended for consumers. The meta-analysis compiled data from 15 studies with a combined total of 1,360 participants and concluded that, if taken within 24 hours after the first appearance of cold symptoms, a daily zinc dose between 50 to 65 milligrams used for at least five consecutive days reduced the duration of a cold by an average of one day.

There were, however, a multitude of different zinc products assessed in the meta-analysis, including syrups and lozenges, so more studies are needed to determine which remedy might work best. ACSH's Dr. Gilbert Ross points out that because “zinc is not a regulated pharmaceutical, the dose and preparation can vary quite a bit from product to product, so it is impossible to determine which form of zinc and which dose is efficacious, if at all, based on this study.”