Herbal supplements are dangerous to the liver
Millions of people take plant-based dietary supplements to promote their health, with turmeric extracts being particularly popular. US scientists have found that consumers can quickly overdose on these products, risking liver damage.
Market research firm Insights10 estimates the German market for plant-based dietary supplements to be around €176 million, with an annual growth rate of 4.4 percent. Particularly popular products include extracts of turmeric, echinacea (coneflower), green tea, and Ginkgo Biloba, as well as omega-3 fatty acids.
People believe that the plants these supplements are based on have health-promoting substances. They also assume that the supplements are similarly or even more healthy. However, this may not be the case.
Unnecessary and dangerous in excess
In moderation, dietary supplements can have a positive effect, "if the right nutrients are taken by the right person at the right time in the right amount," writes the consumer center. However, it also notes that taking such products is usually unnecessary and that their effectiveness and safety are not adequately tested.
Manufacturers must indicate the recommended daily dose and warn against exceeding it. However, consumers often do not read or ignore these instructions, which can be dangerous and, in the case of curcumin derived from turmeric, even lead to liver damage.
Almost 19 million Americans at risk
The safety and effectiveness of plant-based dietary supplements are also not well-established in the US. A research team from the University of Michigan surveyed nearly 10,000 people for a study published in JAMA Network Open. 4.7 percent of them reported taking six potentially hepatotoxic plant-based supplements. These include turmeric, green tea, ashwagandha, milk thistle, Garcinia cambogia, and products with red yeast rice, which the research team says can lead to "potentially severe and even fatal liver damage."
Based on their survey, the scientists estimate that up to 18.6 million Americans consume such products. A study published in the Journal of Emergency Medicine found that the number of supplement-related injuries reported in the US increased by 70 percent between 2010 and 2020 compared to the period from 1994 to 2009.
However, the researchers from the University of Michigan could not establish a causal link between the consumption of plant-based supplements and liver damage, as they were only investigating the use of dietary supplements in the US population. "We don't want to cause panic," says lead author Robert Fontana. "We just want to raise awareness that the over-the-counter dietary supplements that people take and buy are not tested and their safety is not proven."
Turmeric does not help with arthritis
The researchers found that people with chronic diseases such as arthritis and diabetes tend to take plant-based supplements more frequently. These people are also usually older and have a higher level of education and income than those who do not use these dietary supplements.
"Turmeric-containing products were most commonly used for joint health or in cases of osteoarthritis, as there was a widespread belief that turmeric has antioxidant and anti-inflammatory properties," researchers write. "However, several randomized clinical studies have shown no effectiveness of turmeric-containing products in osteoarthritis." The same applies to the other supplements mentioned.
Before taking, consult a doctor
Most participants in the study reported consuming the plant-based substances on their own initiative and not on medical advice. However, the consumer center advises consulting a doctor before taking dietary supplements, as they know about any pre-existing conditions and medications, and can consider possible interactions with these drugs.
Despite the popularity of plant-based dietary supplements, such as turmeric extracts, for promoting health, it's crucial to remember that their safety and effectiveness are not extensively tested. Overdosing on these supplements, as with curcumin from turmeric, can potentially lead to liver damage.
In light of this, it's essential for consumers to carefully follow manufacturers' dosage recommendations and instructions to avoid any unnecessary or dangerous consumption.
