It’s been a natural remedy for liver damage for more than 2,000 years.
And milk thistle shows no signs of going out of vogue.
The spiky, pink-flowering plant was the fourth highest selling supplement at health store chain Holland and Barrett last year, and remains the most popular herbal remedy for liver health in the UK, surveys have shown.
Most milk thistle supplements cost no more than 30p a pill.
Named for its white-veined leaves, milk thistle has long been heralded for its range of healing properties – including combatting indigestion.
But today, milk thistle’s main claim is its liver-healing properties.
Supplements made from the plant’s seeds promise to support liver function, protect against deadly toxins and even help reduce hangovers.
And, unlike many other natural supplements, experts say there is evidence that milk thistle works as promised.
Named for its white-veined leaves – supposedly stained by a drop of the Virgin Mary’s breastmilk, according to folklore – milk thistle has long been heralded for its range of healing properties
In 2021 a major study concluded that patients who took milk thistle saw inflammation in their liver decrease as well as a reduction liver fat – one of the main causes of deadly complications in the organ.
Incredibly, the study found that patients who took the supplement saw improvements to their liver health in as little as two months.
So who should – and shouldn’t be – taking the supplement? And can it help protect against liver damage this Christmas season?
The need for more treatments that protect against liver disease are clear.
Liver health in Britain is currently in dire straits, statistics show – with liver disease mortality rates rising by more than 400 per cent since 1970.
The liver is crucial to removing toxins from the blood. Liver disease stops the organ from doing this job which, overtime, can have life-threatening consequences.
Experts say this worrying rise in liver disease is not solely down to alcohol consumption.
The condition can also be triggered by lifestyle factors such as obesity, type 2 diabetes and lack of exercise.
Just over one in three adults in the UK estimated to have some form of fatty liver disease – a potentially deadly condition where fat builds up in the organ
The lack of symptoms in the early stages can mean that fatty liver disease goes undiagnosed
However, alcohol-related liver disease is also on the rise too.
Deaths from the condition have now reached a record high – around 6,000 in the UK in 2024.
The disease – caused when the chemicals produced by alcohol as it’s broken down damage and kill liver cells – can lead to irreparable inflammation and scarring.
Studies suggest that around seven in ten alcohol-related liver disease patients are undiagnosed, as the condition is often symptomless in its early stages.
Concerningly, it’s not just alcoholics who are affected – regularly drinking over the recommended limit of 14 units of booze per week increases the risk of liver disease.
The British Liver Trust estimates that around one in four people drink alcohol in a way that could harm their health.
And this number is only expected to rise over the Christmas period – when two in three Britons admit drinking too much.
Experts agree that the most effective way to prevent alcohol-related liver disease is to markedly cut back on alcohol consumption.
However, some argue that milk thistle could also play a protective role – particularly at this time of year, when many people struggle to control their drinking.
Milk thistle’s health benefits are mainly due to a chemical found in its seeds, fruit and leaves, called silymarin
Experts say milk thistle’s health benefits are mainly due to a chemical found in its seeds, fruit and leaves, called silymarin.
Silymarin works as an antioxidant, meaning it reduces inflammation in the body. It has also been shown to target and destroy cells responsible for damaging DNA in the body, known as free radicals.
An abundance of these cells can cause what’s known as oxidative stress, which plays a significant role in cancer development and progression.
Experts say that, in the liver, silymarin works like a shield – helping to reduce inflammation, protect from cellular damage and protect the organ from environmental toxins.
In this way, says clinical nutritionist Jane Hutton, who runs the NHS-commissioned Functional Foodie clinic, when taken by otherwise healthy people, milk thistle can enhance the natural functioning of the liver.
‘The liver is the body’s natural filtration system – the healthier it is, the better you’re going to process things, whether that’s paracetamol or alcohol,’ she said.
‘If you’re someone who’s particularly stressed, or has a lot on their plate for a while, milk thistle can be very helpful to give your liver a bit of a boost.’
It can also help repair the liver when it’s damaged, says Alex Glover, senior nutritionist at Holland and Barrett.
‘When the liver is injured, or has problems, it produces higher levels of certain enzymes – the main two being Aspartate Aminotransferase [AST] and Alanine Aminotransferase [ALT],’ he says.
‘There’s been some evidence that milk thistle can actually help to lower these enzymes and improve liver function.’
Research has shown milk thistle can be beneficial for liver ailments ranging from cirrhosis – scarring of the liver – to both non-alcoholic and alcoholic liver disease and even viral hepatitis, a serious liver infection.
The supplement is certainly not a cure-all, says Ms Hutton – and shouldn’t be used in lieu of medication for those with serious liver conditions.
‘There’s no magic bullet for liver health – and the effect milk thistle has will depend on the person taking it,’ said Ms Hutton.
‘Likewise, those on other medications – or with certain medical conditions – should be careful when taking it, as it can interact with other chemicals to have a potentially damaging effect.’
Anyone who is pregnant or breastfeeding, or diabetic should not take milk thistle.
Likewise, certain medicines may interact negatively with the supplement including blood thinners, statins, and anti-seizure medicines.
This is because the liver helps the body breakdown drugs and milk thistle may impact this function.
For some people, milk thistle can also trigger hayfever symptoms in those with the pollen allergy problem.
Most milk thistle supplements contain between 190-260mg of silymarin. Experts say exceeding around 420mg (roughly two tablets) raises the risk of uncomfortable side-effects including diarrhoea and bloating.
If in doubt, says Ms Hutton, always consult a doctor or pharmacist.
And, unfortunately, there’s much less evidence for milk thistle having a beneficial effect on hangovers.
‘The liver is responsible for breaking down alcohol, so it’s been hypothesised that milk thistle, by enhancing this process, can reduce hangovers – but there’s not much evidence to support this,’ says Mr Glover.
For one thing, he says, no one exactly knows what a hangover is – and it’s largely believed to be due to a different biological process: dehydration.
‘If you’re looking for a supplement to take, try curcumin – the active ingredient found in turmeric – as there’s more evidence to suggest that it can help reduce inflammation, which will reduce any headache the next day,’ Mr Glover adds.
COULD THIS £9-A-POP SUPPLEMENT HEAL YOUR LIVER – AND PREVENT A HANGOVER?
At £27 for three vials, it’s certainly the pricier option.
But is trendy liver-boosting supplement De-liver-ance worth the money?
The company’s founder, herbalist Siggi Clavien, certainly thinks so.
‘Milk thistle is a lovely basic herb, and taking it is better than nothing,’ he said.
‘It’s got antioxidant properties and is good for the liver – but it won’t do anything for a hangover.
‘Our liver supplement De-liver-ance, on the other hand, works on a molecular levels to optimise liver function.’
The liquid supplement, which does not contain milk thistle, is packed with polyphenols, which lower blood sugar and inflammation, boost brain power and decrease the risk of cancer.
It also contains 90 times more antioxidants than blueberries, as well as healing and anti-inflammatory herbs like ginseng and astragalus.
In a study of people with fatty liver, De-liver-ance was shown to return the liver to half its full health after just three months, while 83 per cent had lowered its fat levels.
Anecdotal reports also say it’s brilliant for a hangover.
‘For people who can’t afford De-liver-ance, milk thistle will certainly do something. But it’s not going to be anywhere near as effective,’ says Mr Clavien.
