This news may be hard to process.
A new study from the University of Michigan estimates that 15.6 million American adults regularly take herbal and dietary supplements that could be potentially toxic to their liver.
The six supplements are turmeric, green tea, ashwagandha, black cohosh, garcinia cambogia and red yeast rice.
“We weren’t aware that so many people were taking these supplements,” Dr. Alisa Likhitsup, a clinical assistant professor of medicine and lead author of the research, which was published this week in JAMA Network Open.
These supplements appear to be most popular among older, educated white women who seek them out to alleviate arthritis, fatigue and menopausal symptoms.
Nearly 9,700 adults were surveyed between 2017 and 2020 about their supplement intake over a 30-day period.
Among the polled group, turmeric was most popular (3.46%), followed by green tea (1.01%), ashwagandha and black cohosh (0.38%), garcinia cambogia (0.27%) and red yeast rice products (0.19%).
70% of garcinia cambogia users say they take the supplement for weight loss, while 90% of those taking red yeast rice do so to try to improve heart health.
Millions of people around the world consume supplements daily to improve general health, boost immunity and treat minor ailments. US supplement sales surpassed $150 billion last year.
Over 80,000 of these substances — such as multivitamins, minerals and vitamin D, omega-3 fatty acid and calcium products — are available at retail outlets or via the internet.
Researchers noted that hepatotoxicity, or drug-induced liver injury, is on the rise, with supplements accounting for 20% of these cases in the most recent data. They were only responsible for 7% two decades ago.
The study authors said the most commonly implicated botanical products in these cases include turmeric, kratom, green tea extract and garcinia cambogia, leading to “potentially severe and even fatal liver injury.”
The dosage and frequency of usage was not spelled out in the new study.
The study imparts that a large portion of supplements have well-defined ingredients on the label. However, an estimated 5% to 12% are plant-derived, complex multi-ingredient botanicals.
Chemical analyses spurred by liver toxicity show frequent discrepancies between product labels and detected ingredients.
“In a previous study, we found that there was a great deal of mislabeling of some of these products,” explained Dr. Robert Fontana, a Michigan Medicine hepatologist, professor of medicine and the study’s senior author.
“We performed analytical chemistry and found about a 50% mismatch between stated ingredients on the label and what they actually contained, which is quite alarming,” he added. “If you buy a supplement and it says it has a certain ingredient, it’s basically a coin flip if that’s true or not.”
Researchers say frequent mislabeling, along with lack of government regulation and insufficient medical inquiry about supplement use, make these products of great concern.
They hope doctors ask patients if they are taking supplements and consider their effects.
“We’re not trying to create alarm,” Fontana said. “We’re just trying to increase awareness that the over-the-counter supplements people are taking and buying have not been tested nor necessarily proven to be safe.”
