Intake of herbal remedies can pose major risks to health, as illustrated by a historical, political, cultural, and economic discussion of the use of Aristolochia as an herbal supplement. People worldwide use herbal remedies, following millennia of tradition.1
Aristolochia is a genus of 500 plants, many of which are used in herbal remedies in spite of containing the toxin aristolochic acid. Aristolochic acid is a carcinogen and can cause aristolochic acid nephropathy (AAN). People with AAN experience renal failure, interstitial nephritis, and urinary tract cancers.
This discussion, published in EMBO Reports, emphasized that herbal remedies are not necessarily safe, even if they have been used for many years. For example, in genetically susceptible people, consumption of Aristolochia can result in the formation of complexes between aristolactum, a compound in Aristolochia, and DNA in renal tissues.
The formation of these complexes can cause mutations in the TP53 tumor suppressor gene, which can initiate the development of kidney cancer. Other studies suggest that this complex and subsequent mutations might also lead to the development of liver and bladder cancer.
In spite of the toxic dangers of Aristolochia, between 1997 and 2003, 8 million people in Taiwan consumed herbals containing Aristolochia according to the Taiwanese national prescription database. Tens of millions of Chinese and Taiwanese people are at risk of developing AAN due to Aristolochia exposure.
Other herbal and traditional medicines have caused severe adverse events in Africa and Asia, though epidemiologic data are unavailable.
A latency exists between exposure to Aristolochia and the onset of symptomatic disease from toxic effects, making the herbal remedy’s toxicity more challenging to recognize. Only a long-term scientific study of AAN revealed the association of the disease with exposure to Aristolochia. Most carcinogens and many toxins exhibit a latency between exposure and symptoms.
“The history of Aristolachia indicates that other herbs that have been used for a long time may also have toxic and/or carcinogenic compounds,” said the authors.
“It is prudent to assume that many herbs may contain toxic or carcinogenic substances that can cause subsequent health problems for humans.”
This report disagrees with the World Health Organization’s (WHO) support of the use of traditional herbal remedies. The premise of the WHO is that traditional medicine has a proven quality, even though many such remedies lack scientific evidence supporting their efficacy or demonstrating their hazards.
This report suggests “the prevention of toxicities associated with herbal medicine and not a categorical rejection of traditional healing practices. Herbal remedies pose a global hazard. We encourage the global health community to take actions that will evaluate both long- and short-term safety, as well as the efficacy of botanical products in widespread use.”
Reference
1. Grollman AP, Marcus DM. Global hazards of herbal remedies: lessons from Aristolochia [published online ahead of print April 25, 2016]. EMBO Rep. doi:10.15252/embr.201642375.