A six-year study conducted by researchers at the Nigerian Institute of Medical Research (NIMR) has revealed that while most herbal products sold in Nigeria are safe for consumption, their effectiveness in treating diseases remains largely unproven.
Speaking during the institute’s monthly media briefing, Dr. Oluwagbemiga Olanrewaju Aina, Deputy Director of Research in the Department of Biochemistry and Nutrition, explained that the findings emerged from studies conducted by the Centre for Research in Traditional, Complementary, and Alternative Medicine.
“All the 46 herbal products evaluated over the last six years were found to be safe in toxicity studies using animal models. However, none of them passed efficacy tests,
Aina stated.
He noted that since 2019, the Centre has carried out extensive acute and sub-acute toxicity studies on a range of herbal products, including painkillers, anti-malarials, anti-COVID formulations, and remedies for cancer and arthritis. Products such as Kampe Bitters, Divine Herbal Eye Medicine, and Yusram Colon Cleanser were found to be non-toxic at standard dosages.
Sub-acute tests were also performed on high-profile products like COVID Organics Herbal Tea from Madagascar and Vernonia Antiviral Herb, which similarly showed no harmful effects with repeated use in animals.
However, preclinical and clinical efficacy trials painted a different picture. Herbal preparations such as Yoyo Bitters, Timalin, and Jemchi Herbal Remedies failed to demonstrate reliable therapeutic effects against conditions they claimed to treat, including malaria, prostate cancer, and arthritis.
Just because a product doesn’t harm you doesn’t mean it works,” Aina cautioned.
There is a growing trend of herbalists making unverified claims and, in some cases, adulterating their preparations with conventional drugs.”
During the COVID-19 pandemic, the Centre also evaluated several herbal and pharmaceutical products for both safety and efficacy — including Virucidine, Ivermectin, and protein-based immune therapies. Despite widespread public interest, none showed statistically significant clinical benefits compared to standard treatment.
Aina urged herbal medicine producers to move beyond anecdotal claims by identifying and isolating active ingredients in their products and conducting proper scientific trials.
We advise producers of herbal medicines to prove that their ingredients work — not just that they don’t kill,” he said.
A safe drug that doesn’t work is still a public health concern.”
Over the past six years, the Centre has evaluated 46 herbal products, conducted multiple preclinical and clinical studies, and played a vital role in Nigeria’s COVID-19 response. It has also trained over 500 industrial trainees, 150 project students, 50 interns, and 80 PhD students, while collaborating with both local and international universities.
Despite these achievements, Aina acknowledged ongoing challenges, including limited funding, inadequate laboratory infrastructure, and the growing threat of antimicrobial resistance.
He concluded by emphasizing that traditional medicine remains an important part of African healthcare culture but must be supported by scientific evidence:
Herbal therapy has its place — but it must be backed by evidence. Science should validate tradition, not replace it. That is the only way forward