Strong evidencemineral
Zinc for Frequent Colds
Zinc is critical for both innate and adaptive immunity. It supports T-cell development, natural killer cell function, and neutrophil activity. Zinc ions also directly inhibit rhinovirus replication by blocking viral binding to ICAM-1 receptors.
How strong is the research?
Strong evidence
Based on a meta-analysis of multiple studies — the highest level of research evidence.
How much to take
15–30 mg
Daily zinc for prevention. Zinc lozenges (75-90mg/day ionic zinc) within 24 hours of cold onset reduce duration.
When to take it
Best taken: empty stomach