Strong evidenceherb
Echinacea for Frequent Colds
Activates macrophages and increases white blood cell phagocytic activity, enhancing innate immune surveillance.
How strong is the research?
Strong evidence
Based on a meta-analysis of multiple studies — the highest level of research evidence.
Research source
SourceShah SA et al. · Lancet Infect Dis 2007How much to take
300–500 mg
Most effective when started early. Use for acute prevention, not long-term.