Herb Research & Evidence

Evidence snapshot

Counts of PubMed records that mention each herb. A count shows how much has been published, not whether an herb works. Searches match title or abstract words, so they include lab, animal and food research, and curcumin and silymarin are counted with their plants.

Counted 2026-10-22 using NCBI E-utilities. Counts include studies of extracts, blends and non-health topics, and a trial can find no effect. A higher count means more human research has been indexed, not that something works.

What the numbers can mislead about

• Turmeric has hundreds of randomized trials in PubMed, yet NIH says it does not know enough to conclude turmeric or curcumin helps any health purpose. [1]
• Ginkgo has many trials, and NIH says it has not been shown effective for any condition studied. [2]
• Elderberry has far fewer trials, and NIH calls the evidence preliminary. [3]

How to read herb studies

• Which herb, part and product? Extracts differ from foods and teas. [4]
• Human or lab? Laboratory findings do not show what an herb does in people.
• How many people, how long? NIH often notes small, short or poor-quality studies.
• Negative and mixed results count. Saw palmetto, ginkgo for dementia and echinacea for colds are examples of studies that did not support popular claims. [5]
• Who funded it? Check for independent funding.

Gaps

Long-term safety, interactions, best forms and doses are poorly studied for most herbs. See Safety.