NPR Health: Taking Zinc Can Shorten Your Cold. Thank A 91-Year-Old Scientist For The Discovery. “The common cold is a top reason for missed work and school days. Most of us have two or three colds per year, each lasting at least a week.

There’s no real cure, but studies from the last several years show that some supplement containing zinc can help shorten the duration of cold symptoms by up to 40% — depending on the amount of the mineral in each dose and what it’s combined with.”

“Most recently, a meta-analysis published in 2017 by Harri Hemilä at the University of Helsinki concludes that 80 to 92 milligrams per day of zinc, given at the onset of cold symptoms, reduced duration of the common cold by 33%.

The study finds that two different zinc compounds — zinc acetate and zinc gluconate — are both effective. And there’s no evidence, the researchers say, that increasing those doses of zinc (to 100 milligrams per day or more) leads to any greater efficacy.

Great news. Nonetheless, “it’s quite difficult to instruct patients,” says Hemilä, the author of the meta-analysis. That’s because zinc cold formulations sold at drugstores often contain multiple ingredients that can undercut the zinc’s effectiveness. For instance, the lozenges “should not contain citric acid,” Hemilä says, because it binds with the zinc in a way that keeps the mineral from being released. In addition, he says, the mechanism of action is not well understood, so scientists can’t say exactly how it works.

The lozenge used in the Michigan study is not available commercially, Fitzgerald notes. “It was especially designed for the study.””

Well, I have a cold right now (the third since November!), but as far as I can tell, there is not a single zinc supplement available here in Germany that contains the right amount of zinc in the right compound (acetate or gluconate). Many capsules also contain citric acid, which the study says binds the zinc.

I guess it’s back to lots of fluids and plenty of sleep for me. Achoo!