If you ask me, Chinese herbal medicines are best avoided

Many patients seek Chinese herbal medicines (CHM) from traditional Chinese medicine (TCM) clinics. This study aimed to estimate the risk of major adverse cardiovascular events (MACEs) in adults diagnosed with obesity, with or without CHM.

Patients with obesity aged 18 to 50 years were identified using diagnostic codes from Taiwan’s National Health Insurance Research Database between 2008 and 2018. The researchers randomized 67,655 patients with or without CHM using propensity score matching. All patients were followed up from the start of the study until MACEs, death, or the end of 2018. A Cox proportional regression model was used to evaluate the hazard ratios of MACEs in the CHM and non-CHM cohorts.

During a median follow-up of 4.2 years, the CHM group had a higher incidence of MACEs than the non-CHM control cohort (9.35 versus 8.27 per 1,000 person-years). The CHM group had a 1.13-fold higher risk of MACEs compared with the non-CHM control (adjusted hazard ratio [aHR] = 1.13; 95% confidence interval [CI]: 1.07–1.19; p <0.001), especially in ischemic stroke (aHR = 1.18; 95% CI: 1.07–1.31; p <0.01), arrhythmia (aHR = 1.26; 95% CI: 1.14–1.38; p <0.001), and young adults aged 18 to 29 years (aHR = 1.22; 95%
CI: 1.05–1.43; p <0.001).

The authors concluded that, although certain CHMs offer cardiovascular benefits, young and middle-aged obese adults receiving CHM exhibit a higher risk of MACEs than those not receiving CHM. Therefore, TCM practitioners should be cautious when prescribing medications to young patients with obesity, considering their potential cardiovascular risks.

I am not sure why the authors concluded that “certain CHMs offer cardiovascular benefits”; their data do not support this statement and I am not aware of any such evidence either. The more valid result of this study is that the use of CHMs is a risk factor for cardiovascular health in obese people. I fear that this might also be true for non-obese individuals and could also apply to non-cardiovascular areas of health.

Just like any other form of herbal therapy, CHMs can contain toxic ingredients and might interact with prescribed medications. Unlike most other forms of herbal treatments CHMs are known to be often contaminated (e.g. with heaviy metals) and/or adulterated (e.g. with illegal amounts of synthetic drugs). as they typically contain a multitude of herbs, the risk of interactions is also increased. Our 2013 review shoed that “herbal medicinal products (HMPs) were adulterated or contaminated with dust, pollens, insects, rodents, parasites, microbes, fungi, mould, toxins, pesticides, toxic heavy metals and/or prescription drugs. The most severe adverse effects caused by these adulterations were agranulocytosis, meningitis, multi-organ failure, perinatal stroke, arsenic, lead or mercury poisoning, malignancies or carcinomas, hepatic encephalopathy, hepatorenal syndrome, nephrotoxicity, rhabdomyolysis, metabolic acidosis, renal or liver failure, cerebral edema, coma, intracerebral haemorrhage, and death. Adulteration and contamination of HMPs were most commonly noted for traditional Indian and Chinese remedies, respectively.”

My advice has therefore long been very clear and outspoken:

CHMs are best avoided!