Green juices, herbal teas, liquid doses and three-day programmes: a liver detox promises to “clean” an organ imagined to be clogged by excess. The idea is appealing, but rests on a misunderstanding. The liver does not need a course of treatment to remove waste: that is its continuous job. Here is how it really works, what detox programmes are worth, what actually protects it, what studies say about artichoke, black radish and milk thistle, and which supplements may harm it.
Key takeaways
- The liver continuously transforms and removes unwanted substances through bile and urine, without needing a detox course.
- According to a 2015 review, no randomised trial had evaluated commercial detox diets in humans.
- Limiting alcohol, losing weight when overweight and being active are the measures recommended for liver health.
- Some supplements can damage the liver. The only authorised health claim concerning the liver relates to choline.
How does the liver actually remove toxins?
The liver is the body's main processing plant. Medicines, alcohol, pollutants and used hormones: many of these substances are fat-soluble, making them difficult to remove as they are. The liver makes them more water-soluble through several steps that pharmacologists call “phases”.
- Phase I: transformation. Enzymes, particularly the large cytochrome P450 family, modify the molecule, often by oxidation. This step can produce intermediates more reactive than the original substance, making the next step important.
- Phase II: conjugation. The liver attaches a group to the molecule that makes it soluble, such as glucuronic acid, a sulphate, amino acids (glycine or taurine), or glutathione, a major antioxidant in our cells.
- Phase III: removal. Transporters move these products out of the cells. They leave the body through bile, which enters the intestine and then the stools, or pass into the blood to be filtered by the kidneys and eliminated in urine.
This system works continuously, without outside intervention. When liver glutathione is depleted, as in paracetamol poisoning, a hospital administers N-acetylcysteine (NAC) to replenish it: this is an antidote, not a cleansing course.
Is a liver detox course useful?
There is no evidence that it is. A critical review published in 2015 found that no randomised trial had evaluated commercial detox diets in humans. The few available studies have weak methods and small samples. Suggested possibilities for certain foods, such as coriander or nori seaweed, are mainly based on animal studies.
As for the weight loss often promised, the same review found no robust evidence that it is lasting.
What really damages the liver?
Major causes of liver disease include alcohol, viral hepatitis and fat accumulation associated with overweight, known as steatosis. The latter, now called metabolic dysfunction-associated steatotic liver disease (MASLD), affects around 30% of adults worldwide. Its prevalence is rising: 25% over 1990–2006, and 38% over 2016–2019. Often silent, it can progress to liver inflammation, fibrosis and then cirrhosis.
What really protects the liver
The 2024 European guidelines on fatty liver disease are based on straightforward measures: weight loss, dietary changes, physical activity and limiting alcohol.
- Limit alcohol: Santé publique France recommends no more than 10 standard drinks per week and 2 drinks per day, with alcohol-free days.
- Lose weight if overweight: among 293 patients with steatohepatitis followed for one year, those who lost at least 10% of their weight had resolution of steatohepatitis in 90% of cases and regression of fibrosis in 45%.
- Be active: physical activity is a recommended measure, alongside diet.
- Avoid self-medication: medicines, herbs and supplements all pass through the liver. Tell your doctor about them.
Artichoke, black radish and milk thistle: what do studies say?
These three plants are the stars of “liver” formulas. The strength of evidence varies considerably.
Artichoke
A meta-analysis of 5 randomised trials involving 333 patients with fatty liver observed reductions in transaminases (ALT and AST), total cholesterol, LDL and triglycerides with artichoke leaf extract. These trials remain short and modest in size.
Black radish
Human data are limited to one pilot trial: 20 healthy men took a black radish supplement for 4 weeks, with no placebo group. The handling of a test dose of paracetamol changed, which the authors interpreted as stimulation of liver enzymes. The study was funded by the product manufacturer. This is too little to conclude that there is an effect in humans.
Milk thistle
This is the most studied plant. A Cochrane review of 18 trials involving 1,088 patients found no effect on mortality in liver disease associated with alcohol or hepatitis B and C. Findings in fatty liver disease are mixed. We discuss these trials in our article on milk thistle and silymarin.
| Ingredient | Human evidence | What was measured | Strength of evidence |
|---|---|---|---|
| Artichoke (leaf) | 5 trials, 333 patients | Transaminases, blood lipids | Limited |
| Black radish | 1 pilot trial, 20 men | Paracetamol metabolites | Very low |
| Milk thistle | Cochrane review, 18 trials | Mortality, complications | No demonstrated effect |
| Choline | Nutrient | Liver function | Authorised health claim |
Which supplements can damage the liver?
Natural does not mean risk-free. In the United States, the proportion of liver injuries attributed to herbs or supplements rose from 7% to 20% of cases recorded by a specialist network between 2004 and 2013. Supplement-related injuries, excluding bodybuilding products, were more severe than medicine-related injuries: 13% resulted in death or transplantation, compared with 3%.
- Green tea extracts: the NIH LiverTox database records acute injuries, sometimes fatal or requiring transplantation. EFSA concluded in 2018 that an intake of at least 800mg of EGCG per day, its main compound, increases transaminases.
- Turmeric: in France, ANSES recorded more than 100 reports of adverse effects associated with turmeric supplements, including 15 cases of hepatitis. It advises against these products in people with biliary tract disease and warns about formulas with enhanced absorption.
If unusual fatigue, jaundice or dark urine occurs while taking a supplement, stop it and seek medical advice.
The only authorised health claim for the liver: choline
In the European Union, only one health claim mentions the liver: “choline contributes to the maintenance of normal liver function”. It is restricted to products providing at least 82.5mg of choline per 100 g, 100 ml or serving. No plant, including artichoke, black radish or milk thistle, has an authorised health claim. Food sources of choline and requirements are detailed in our article on choline.
Frequently asked questions
Can you cleanse your liver in 3 days?
No. No short course has been shown to “empty” the liver of anything: it continuously transforms and removes unwanted substances. After overindulging, the most useful steps remain planning alcohol-free days and returning to a balanced diet.
Does a liver detox help you lose weight?
The 2015 review of detox diets found no robust evidence of lasting weight loss. The reverse is more accurate: gradual weight loss achieved through diet and physical activity reduces liver fat.
Do lemon or apple cider vinegar cleanse the liver?
No trial has shown this. These drinks can have a place in a varied diet, but there is no indication that they change how the liver works.
Should you detox in spring or after the holidays?
There is no physiological reason to “purge” the liver at a particular time of year. After the holidays, the useful step is simply to reduce alcohol and excess, then return to your usual habits.
How can you tell whether your liver is healthy?
Liver diseases often remain silent for a long time. In cases of type 2 diabetes, obesity or abnormal liver tests, European guidelines recommend assessing fibrosis with a blood test (FIB-4 score), followed if necessary by elastography, a painless examination of liver stiffness.
Which foods are good for the liver?
No food “cleanses” the liver. What matters is the overall balance: a diet that avoids weight gain, little alcohol and regular physical activity.
Conclusion
Liver detox as promised by commercial programmes is more myth than reality: the liver itself transforms and removes unwanted substances, and commercial courses have not been validated by randomised trials. What actually protects the liver is less dramatic, but better supported: less alcohol, weight loss if overweight, physical activity and targeted screening. Among plants, artichoke shows signals in blood markers, black radish remains scarcely studied, and milk thistle has not demonstrated an effect on mortality. Finally, some supplements can themselves damage the liver: talk to a healthcare professional before taking them.
Sources
- Almazroo OA, Miah MK, Venkataramanan R (2017). Drug Metabolism in the Liver. Clinics in Liver Disease, 21(1), 1-20. doi:10.1016/j.cld.2016.08.001
- Klein AV, Kiat H (2015). Detox diets for toxin elimination and weight management: a critical review of the evidence. Journal of Human Nutrition and Dietetics, 28(6), 675-686. doi:10.1111/jhn.12286
- Younossi ZM et al. (2023). The global epidemiology of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH): a systematic review. Hepatology, 77(4), 1335-1347. doi:10.1097/HEP.0000000000000004
- EASL, EASD, EASO (2024). EASL-EASD-EASO Clinical Practice Guidelines on the management of metabolic dysfunction-associated steatotic liver disease (MASLD). Journal of Hepatology, 81(3), 492-542. doi:10.1016/j.jhep.2024.04.031
- Santé publique France (2019). Alcohol and health: Santé publique France commits to a risk reduction strategy. Press release of 19 February 2019. santepubliquefrance.fr
- Vilar-Gomez E et al. (2015). Weight Loss Through Lifestyle Modification Significantly Reduces Features of Nonalcoholic Steatohepatitis. Gastroenterology, 149(2), 367-378.e5. doi:10.1053/j.gastro.2015.04.005
- Kamel AM, Farag MA (2022). Therapeutic Potential of Artichoke in the Treatment of Fatty Liver: A Systematic Review and Meta-Analysis. Journal of Medicinal Food, 25(10), 931-942. doi:10.1089/jmf.2022.0025
- Evans M, Paterson E, Barnes DM (2014). An open label pilot study to evaluate the efficacy of Spanish black radish on the induction of phase I and phase II enzymes in healthy male subjects. BMC Complementary and Alternative Medicine, 14, 475. doi:10.1186/1472-6882-14-475
- Rambaldi A, Jacobs BP, Gluud C (2007). Milk thistle for alcoholic and/or hepatitis B or C virus liver diseases. Cochrane Database of Systematic Reviews, (4), CD003620. doi:10.1002/14651858.CD003620.pub3
- Navarro VJ et al. (2014). Liver injury from herbals and dietary supplements in the U.S. Drug-Induced Liver Injury Network. Hepatology, 60(4), 1399-1408. doi:10.1002/hep.27317
- LiverTox (regularly updated). Green Tea. LiverTox: Clinical and Research Information on Drug-Induced Liver Injury, National Institute of Diabetes and Digestive and Kidney Diseases. PubMed 31643260
- EFSA ANS Panel (2018). Scientific opinion on the safety of green tea catechins. EFSA Journal, 16(4), e05239. doi:10.2903/j.efsa.2018.5239
- ANSES (2022). Adverse effects associated with the consumption of food supplements containing turmeric (opinion 2019-SA-0111). anses.fr
- European Commission (2012). Regulation (EU) No 432/2012 of 16 May 2012 establishing a list of permitted health claims made on foods, other than those referring to the reduction of disease risk and to children's development and health. Official Journal of the European Union, L 136, p. 1 (consolidated version). eur-lex.europa.eu
Food supplements do not replace a varied, balanced diet or a healthy lifestyle. Ask a healthcare professional for advice if you are taking medication, pregnant or breastfeeding.
