Black elderberry (Sambucus nigra) supplementation effectively treats upper respiratory symptoms: A meta-analysis of randomized, controlled clinical trials

Hawkins, J., Baker, C.

Published in Complementary Therapies in Medicine

Abstract

Systematic review of elderberry extract for upper respiratory symptoms

Methodology

Meta-analysis of four randomised, placebo-controlled trials (180 participants) of black elderberry supplementation for upper respiratory symptoms caused by cold or influenza, pooling symptom duration and severity data.

Key Findings

Elderberry supplementation substantially reduced upper respiratory symptom duration and severity compared with placebo, with a larger effect in influenza than in common cold and no increase in adverse events. The pooled effect size was large but rested on only four small trials.

Conclusions

Elderberry appears to shorten and soften upper respiratory symptoms and is a reasonable adjunct for symptom relief, but the small and partly industry-linked evidence base means the effect size is likely overstated.

Limitations

Only four trials totalling 180 participants; heterogeneous preparations and doses; self-reported symptom scales; potential publication bias and industry involvement; no data on hard outcomes such as complications or hospitalisation.