Tilda Pattman put her cough, sleeplessness and fatigue down to the lingering effects of Covid. And as someone who’d previously taken supplements for her health, she decided to try and boost her recovery ‘naturally’ with a cocktail of nutrients bought online: green tea, black seed, turmeric, ginseng, melatonin and ashwagandha.

These are popular remedies – green tea is often taken for antioxidant benefits; black seed for supporting immunity; turmeric for reducing inflammation; ginseng for energy; melatonin for sleep; and ashwagandha – a herb used in traditional Ayurvedic medicine – also for sleep.

Yet within three weeks of starting her supplement ‘health kick’, the retired intensive care nurse from Nottingham developed liver failure and needed an emergency transplant. She then spent ten months in hospital, so ill she has virtually no recollection of it.

Alarmingly, doctors warn cases of liver failure are rising as more people turn to supplements to ‘boost’ their health, often taking several at once and unaware high-strength extracts can deliver far larger doses than the foods and drinks they are derived from.

Many online products are also unregulated and can contain toxic ingredients that aren’t on the label, according to the Food Standards Agency (FSA), which regulates supplements (because they’re classed as food).

‘Herbal and dietary supplements account for 6 per cent of the acute liver injuries caused by medicines in Britain,’ says Professor Guruprasad Aithal, a consultant liver specialist at Nottingham University Hospitals NHS Trust and a leading expert on liver damage caused by medicines and supplements.

And the problem is that, unlike the gradual scarring caused by years of heavy drinking or obesity, this potentially life-threatening damage can strike within weeks.

This is because, as the liver breaks down concentrated plant extracts, it can produce toxic by-products which rapidly damage and even kill liver cells. It doesn’t do this when we consume those same nutrients, in lower concentrations, from our diet.

Within three weeks of starting her supplement ‘health kick’, Tilda Pattman developed liver failure and needed an emergency transplant

She used a cocktail of nutrients bought online: green tea, black seed, turmeric, ginseng, melatonin and ashwagandha

Supplements can also trigger an abnormal immune system attack on the liver in some people. This happens when a component in the supplement, or a chemical created as the liver processes it, attaches to proteins in liver cells.

In people with a particular gene variant (that affects one in ten of us), the immune system mistakes these liver cells as a threat and destroys them – even if you’re taking supplements at the right dose.

If liver cells are destroyed faster than they can be replaced, the organ can rapidly fail.

Yet early liver injury may cause no symptoms, or only vague tiredness, nausea or itching – abnormal blood tests may be the first warning sign.

Tilda started taking her supplements around mid-January 2022 – over the next few weeks she felt increasingly exhausted, recalls the mother of three, now aged 72. She was also in ‘a lot of pain’ and constipated.

But it wasn’t until one lunchtime in early February that she realised something was seriously wrong.

Her daughter, Audrey (who lives in the US), had video-called and was alarmed by the colour of her mother’s eyes, which had turned yellow.

Tilda then checked her palms – these were yellow too, the telltale signs of jaundice (caused by a build-up of bilirubin, a yellow waste pigment), a sign of liver damage.

Alarmingly, doctors warn cases of liver failure are rising as more people turn to supplements to ‘boost’ their health

‘Very worried’, Tilda, managed to get herself to Queen’s Medical Centre in Nottingham. After seeing her blood test results and realising how ill she was, doctors were astonished she’d made it to the hospital alone.

But over the next 48 hours her liver failed, unable to clear toxins from her blood or produce the proteins needed for it to clot.

Tilda, who by now had become confused and began hallucinating, was rushed to the specialist liver unit at Addenbrooke’s Hospital in Cambridge and given an emergency transplant – just five days after her daughter’s call (acute liver failure can qualify a patient for the super-urgent liver list).

During the 14-hour transplant operation, Tilda’s heart began to fail – 24 hours later, her family was told that it was barely pumping and if she showed no improvement, doctors could withdraw life support.

‘We were just pretty much sitting and waiting for her heart to give out,’ says Audrey, who had flown home to be with her mother. The family pleaded with doctors to do a brain scan before making a final decision.

The scan results, together with a slight improvement in her blood tests, spurred on the team to continue treatment. Tilda’s heart subsequently began pumping properly again.

‘I was in a lot of pain and had no idea what was happening,’ recalls Tilda. ‘After being admitted to Addenbrooke’s, I remember almost nothing until December that year.’ The scale of the damage became clear after her liver had been removed. Professor Aithal, who treated her, says: ‘Most of the liver cells had died.’

After alcohol and other medical explanations were ruled out, there was ‘no other cause’ for Tilda’s acute liver failure than ‘the supplements she was taking’, he says.

Hers – although extreme – is not an isolated case, says Professor Aithal. He describes a spectrum of liver damage from supplements: many patients suffer liver injury, while some will go on to develop acute liver failure.

The first multinational study to investigate patients with suspected drug-induced liver injury, led by Professor Aithal, found that 7 per cent of confirmed cases were due to herbal or dietary supplements.

Antibiotics, most commonly co-amoxiclav and flucloxacillin, accounted for 40 per cent of cases; a further 27 per cent were linked to cancer treatments or immune-suppressing drugs such as infliximab and azathioprine, prescribed for conditions such as rheumatoid arthritis, reported the journal Liver International in 2023.

And the incidence of supplement-related damage is growing.

Another study, published in Liver Transplantation in 2022, based on US patients on the transplant waiting list with acute liver failure caused by supplements, showed cases rose more than eightfold between 2003 and 2020.

Professor Aithal says liver specialists are seeing more supplement-related acute liver failure here too.

What particularly concerns them is the speed at which patients can deteriorate. A toxic reaction to a supplement can kill large numbers of liver cells and lead to acute liver failure within just a week to three months, Professor Aithal explains.

‘It is unlike the damage from alcohol and obesity, where scarring generally takes years to build up.’ Once this happens, the effects can spread rapidly. ‘The liver can no longer remove toxins from the blood,’ he says, affecting the function of the brain, kidneys and blood circulation.

Patients can experience confusion or hallucinations and multi-organ failure – and death.

The concern is now so great that the FSA launched a major investigation last month after receiving increasing reports of serious and sometimes fatal liver damage linked to supplements.

Products under scrutiny include concentrated green-tea extract (the single remedy most frequently named in the reports); turmeric extracts (particularly those containing piperine, see below), ashwagandha, Garcinia cambogia (a tropical fruit, it contains hydroxycitric acid and is marketed for weight loss); as well as multi-ingredient ‘detox’, fat-burning and bodybuilding supplements.

This last group were most often mentioned in the reports – they regularly contain green tea extract, said to increase metabolism and weight loss; turmeric, due to its anti-inflammatory and joint benefits; and ashwagandha, claimed to improve strength, muscle growth and recovery, and reduce stress.

Bodybuilding products may include undeclared or illicit substances, including anabolic steroids, which can stop bile draining from the liver, causing jaundice.

The FSA cited turmeric as an example of how turning a familiar food into a high-strength supplement may alter its risks.

Its main active ingredient is curcumin, the chemical credited with its supposed benefits. But curcumin is normally poorly absorbed by the body, so some manufacturers add piperine, a black-pepper extract which allows up to 20 times more curcumin to enter the bloodstream.

As a result the liver may be exposed to far more curcumin than it would encounter from turmeric used in cooking – but Professor Aithal says this is safe unless you have a gene variant, known as HLA-B*35:01 (only a genetic test can show whether someone carries it).

This variant can provoke an abnormal immune response which causes the immune system to attack liver cells. A 2023 study in The American Journal of Medicine found that seven out of ten patients in the US who developed liver damage after taking turmeric supplements carried HLA-B*35:01.

Meanwhile, green tea extracts contain concentrated levels of catechins, particularly epigallocatechin gallate (EGCG). This acts as an antioxidant but, in high doses, it can become toxic to liver cells, says Professor Aithal.

In a 2021 US study, published in the journal Hepatology, green tea extract was the most common cause of liver damage in patients treated in specialist liver centres.

Worryingly, the damage wasn’t dependent on the dose (which ranged from 50mg to 2,000mg a day). The study also found that 72 per cent of the patients tested carried HLA-B*35:01.

However, genes don’t explain every case, says Professor Aithal. Concentrated extracts may also overwhelm the liver directly, while chemicals added to some fat-burning products can disrupt the mitochondria – the tiny ‘batteries’ in all cells – in the liver, and eventually kill the cells, he says.

‘Detox’, fat-burning and bodybuilding supplements which combine numerous ingredients in a single capsule or powder are also of concern. Some contain ten to 15 herbal extracts, vitamins and other chemicals, says Professor Aithal. The strength of each may not be clear and the contents can vary from one batch to another.

‘What the label says is in the product may not reflect the true ingredients,’ he says.

Behind the rise in cases is the problem that food supplements can be marketed for insomnia, fatigue or anxiety, aid weight loss or even to ‘repair’ the liver – but, because they are classed as food, they don’t undergo the same testing or monitoring as medicines.

‘There is a widespread belief that products available over-the-counter have undergone the same rigorous testing – in reality, supplements are regulated differently and often reach the market without the type of clinical evidence required for pharmaceutical products,’ says Stephen Ryder, a consultant hepatologist at Nottingham University Hospitals NHS Trust and a professor of medicine at the University of Nottingham.

‘Social media and influencer marketing may also reinforce the idea that these products are harmless wellness aids rather than products with the potential for side-effects,’ he says.

‘Many people assume that “natural” means “safe”, but that is not necessarily true,’ he adds – as Tilda’s story highlights.

After her transplant her kidneys stopped working and she needed dialysis as well as a ventilator to keep her alive.

Tilda’s recovery took most of the following year. But she has since made a remarkable recovery and now walks three-and-a-half miles a day, and has been able to travel, including to see her daughter in the US.

‘I live on my own, I manage my own affairs, I drive, I can do everything. I have my life back,’ Tilda says. ‘I went for 48 hours with only 1 per cent of my heart working – everyone was waiting for a flatline. The only explanation I have is that God saved me – alongside the NHS staff working so hard to treat me. Without them I would not be alive.’