Herbal supplements and traditional Chinese medicines can contain some seriously dangerous stuff
So the ingredients they say they contain aren't always accurate, and the products might not fix what they claim they will.
Sometimes, these medicines, which are often sold as powders or pills, also contain metals like lead, mercury, and arsenic, which are highly toxic in large doses.
A study, published Dec. 10 in Scientific Reports, found dangerous or toxic substances in nearly 90% of the traditional Chinese medicine samples gathered in Australia.
The authors identified the presence of pharmaceuticals - including antihistamines, anti-inflammatories, antibiotics, stimulants, and the blood thinner warfarin - in many medicines sold as herbal supplements. Over half of the medicines had significant amounts of heavy metals like arsenic, cadmium and lead.
Of the 26 traditional Chinese medicines analyzed using tests for DNA, heavy metals, and toxic substances, only two had no detectable ingredients that were potentially harmful.
The following Venn diagram shows which products were "non-compliant" from each of these tests, meaning they wouldn't be allowed to be sold in Australia if they were tested, since they contained toxic metals, ingredients not listed on the label, or even illegal contents.
Each number in the diagram corresponds to one of the 26 samples; only the two samples in the "undetected" box came out clean, while the six samples in the middle were non-compliant for at least three reasons:
While this study was only done on products found in Australia, the problem exists in the US, as well. Previous research has found heavy metals in Indian Ayurvedic medicines in Boston and from products bought in the US on the internet.
Yet the herbal medicine industry represents billions of dollars worldwide, study co-author Ian Musgrave from the University of Adelaide wrote in a blog post on The Conversation.
"Globally," he wrote, "we need a better auditing 'toolkit' to ensure consumers of herbal medicines, as well as people testing their efficacy, are not being misled."