A growing number of individuals are experiencing severe liver damage, including acute liver failure, linked to the consumption of herbal and dietary supplements, according to medical experts.
Doctors warn that concentrated extracts found in popular supplements for sleep, energy, and weight loss can cause lasting liver damage, sometimes within weeks of use. This phenomenon is contributing to a rise in acute liver injuries that were previously rare.
One case highlighted involved Tilda Pattman, a 72-year-old retired intensive care nurse who developed liver failure and required an emergency transplant after taking a combination of supplements including green tea, black seed, turmeric, ginseng, melatonin, and ashwagandha for three weeks to aid her recovery from Covid-19. She spent ten months in hospital, with little memory of the ordeal.
Professor Guruprasad Aithal, a consultant liver specialist at Nottingham University Hospitals NHS Trust and an expert in drug-induced liver injury, stated that herbal and dietary supplements account for 6% of acute liver injuries caused by medicines in Britain. He noted that, unlike gradual scarring from alcohol or obesity, this damage can strike rapidly. When the liver breaks down concentrated plant extracts, it can create toxic by-products that damage or kill liver cells. This can occur even when consuming the same nutrients in lower concentrations through diet.
Supplements can also trigger an autoimmune attack on the liver in susceptible individuals. This occurs when a supplement component, or a chemical produced during its breakdown, attaches to liver cell proteins. In people with a specific gene variant (affecting about 10% of the population), the immune system mistakenly identifies these altered liver cells as a threat and destroys them.
Early symptoms of liver injury can be vague, such as tiredness, nausea, or itching, with abnormal blood tests often being the first indicator. Pattman experienced increasing exhaustion, pain, and constipation before her eyes and palms turned yellow, indicating jaundice and significant liver damage.
She was admitted to Queen’s Medical Centre in Nottingham, where her liver failed within 48 hours. She was then transferred to Addenbrooke’s Hospital in Cambridge for an emergency transplant. During the operation, her heart also experienced failure, and her family was initially told her condition was critical.
Professor Aithal indicated that Pattman’s acute liver failure was attributed to the supplements she was taking, with most of her liver cells having died. He described a spectrum of liver damage from supplements, where some patients develop acute liver failure.
A multinational study led by Professor Aithal found that 7% of confirmed drug-induced liver injuries were due to herbal or dietary supplements. This contrasts with antibiotics, which accounted for 40% of cases, and cancer treatments or immune-suppressants, which accounted for 27%.
Further research from a 2022 US study showed that cases of acute liver failure caused by supplements in patients on the transplant waiting list rose more than eightfold between 2003 and 2020. Liver specialists are observing a similar increase in supplement-related acute liver failure.
The speed at which patients can deteriorate is a major concern. Toxic reactions to supplements can destroy liver cells and lead to acute liver failure within one week to three months, a pace significantly faster than damage from alcohol or obesity.
The Food Standards Agency (FSA) has launched an investigation into serious and potentially fatal liver damage linked to supplements. Products under scrutiny include concentrated green-tea extract, turmeric extracts, ashwagandha, and Garcinia cambogia, as well as multi-ingredient "detox," fat-burning, and bodybuilding supplements. These multi-ingredient products often contain combinations of green tea extract, turmeric, and ashwagandha, among other substances.
Bodybuilding supplements, in particular, may contain undeclared or illicit substances like anabolic steroids, which can impede bile flow and cause jaundice.
The FSA used turmeric as an example of how transforming a common food into a high-strength supplement can alter its risk profile. The active compound curcumin in turmeric is poorly absorbed, so manufacturers often add piperine to enhance absorption. While this may be safe for most, individuals with a specific gene variant, HLA-B*35:01, may experience an abnormal immune response that attacks liver cells. A 2023 study found that seven out of ten US patients who developed liver damage from turmeric supplements carried this gene variant.
Similarly, high doses of catechins, particularly epigallocatechin gallate (EGCG), found in green tea extracts, can be toxic to liver cells. A 2021 US study identified green tea extract as the most common cause of liver damage in patients treated at specialist liver centers, with 72% of tested patients carrying the HLA-B*35:01 gene variant.
However, experts note that genetic factors do not explain all cases. Concentrated extracts can directly overwhelm the liver, and some chemicals in fat-burning supplements can disrupt liver cell mitochondria, leading to cell death.
The lack of rigorous testing and regulation for supplements, which are classified as food, is a significant concern. Unlike pharmaceuticals, supplements do not undergo the same clinical trials or monitoring. "Many people assume that 'natural' means 'safe', but that is not necessarily true," said Stephen Ryder, a consultant hepatologist at Nottingham University Hospitals NHS Trust. He also pointed to social media and influencer marketing that can promote these products as harmless wellness aids.
Following her transplant and a period of critical illness, Tilda Pattman has recovered and resumed an active life, expressing gratitude for her survival and the care she received.