The goal of this living map of evidence is to act as a resource, attesting to the abundance and nature of the published peer-reviewed evidence being synthesized on natural health products (NHPs) for the prevention of COVID in the form of research reports that have used a systematic (and reproducible) strategy.

Statistical Overview – as of April 2023

Number of systematic reviews investigating the use of natural health products for the prevention of COVID: 68

Number of studies included in those reports: 2,153*

Number of participants included: 17,239,640*

*Note: numbers were not included in all papers.









22 countries included. Most common:

Iran – 11 (18%)
China – 7 (11%)
United Kingdom – 7 (11%)
India – 5 (8%)
Italy – 5 (8%)
Brazil – 4 (7%)









Most common NHPs include:

Vitamin A – 44 (28%)
Vitamin D – 44 (28%)
Zinc – 11 (7%)
Selenium – 10 (6%)

Search terms: systematic review, COVID, COVID-19, SARS-CoV-2, “Severe acute respiratory syndrome coronavirus 2″, “viral respiratory tract infections”, “naturopathic treatment”, “Traditional Chinese medicine”, nutraceutical, “natural product” botanical, herb, “herbal medicine”, “medicinal herbs”, “medicinal plants”, vitamin, mineral