Zinc
Essential trace element for the immune system, usually taken as a lozenge or capsule during a cold.
What the research shows
Shown, with a clear condition or a limited scope.
The Cochrane review by Nault (2024) found signs that zinc shortens a cold by roughly two days, with low certainty because the trials differed widely. Wang (2020) reported a comparable shortening in healthy adults. No reliable effect on catching a cold was seen, and high doses often cause a bad taste and nausea.
Who it makes sense for: Adults who start at the first symptoms of a cold, and people with a low zinc intake such as vegans.
How we weigh evidenceClinical dosage
Scientific sources
The clinical dosages on this page are based on peer-reviewed research.
We keep the dosages and values on this page as accurate as possible based on selected studies. New research may change these values. Nothing on this page is medical advice. If you have any doubts, always consult a doctor.