02Research · Supplement
Milk Thistle
Measured against the 58-marker panel. Human studies found an effect on 25, no change in 4 and conflicting results on 0; 29 have no result yet.
Most studied for
Hepatoprotection - general (NAFLD, elevated liver enzymes, toxic hepatitis, alcoholic liver disease)
01Read first
Who should be careful
Cautions14
SeriousAsteraceae/Compositae family allergyGrade B
Cross-reactivity with milk thistle (Silybum marianum) in patients allergic to ragweed, chrysanthemums, marigolds, daisies. Anaphylaxis cases documented in FAERS.
SeriousConcurrent narrow-TI immunosuppressants (cyclosporine, tacrolimus, sirolimus, everolimus)Grade B
CYP3A4 + P-gp inhibition significantly elevates immunosuppressant levels. Risk compounded in cirrhotic transplant recipients with disease-altered transporter expression.
SeriousPregnancyGrade C
Insufficient human safety data. Silymarin crosses placenta in animal models.
SeriousActive biliary obstruction or acute cholangitisGrade C
Silymarin has choleretic/cholagogue activity — stimulates bile production. In biliary obstruction, increased bile production without egress may worsen biliary pressure, pain, and infection risk.
Show 10 more
SeriousHormone-sensitive malignancies (ER+ breast cancer, uterine cancer, ovarian cancer)Grade C
Silymarin has documented both estrogenic and anti-estrogenic activity in vitro. Net in vivo hormonal effect uncertain but may theoretically stimulate hormone-responsive tumor tissue.
SeriousIrinotecan therapy in UGT1A1*28 homozygotesGrade C
UGT1A1*28/*28 already impairs SN-38 glucuronidation. Silymarin's additional UGT1A1 inhibition may compound risk of severe neutropenia and diarrhea.
ModerateConcurrent anticoagulation (warfarin, acenocoumarol) without INR monitoring accessGrade B
CYP2C9 inhibition increases S-warfarin exposure. INR elevation and hemorrhagic events documented.
ModerateDiabetes on insulin or sulfonylureas without glucose monitoringGrade B
Additive blood glucose lowering (AMPK activation, insulin sensitization) may precipitate symptomatic hypoglycemia.
ModerateHepatic decompensation — Child-Pugh C cirrhosisGrade C
Drug interaction profile shifts in cirrhosis.
ModerateSevere renal impairment (eGFR <30 mL/min/1.73m²)Grade C
Accumulation risk in CKD 4–5.
ModeratePre-surgical / Perioperative periodGrade C
CYP3A4 inhibition may affect anesthetic drug metabolism (midazolam, fentanyl).
ModerateLactation / BreastfeedingGrade D
Transfer into breast milk unknown; insufficient infant safety data.
ModeratePediatric patients (<18 years)Grade D
No controlled safety or efficacy data in pediatric populations. CYP enzyme ontogeny and UGT maturation differences may alter drug interaction profile.
ModerateG6PD deficiency (high-dose or IV use)Grade D
G6PD-deficient RBCs are more vulnerable to oxidant stress.
Interactions18
SeriousWarfarinGrade B
CYP2C9 inhibition reduces S-warfarin clearance; possible CYP3A4 contribution for R-warfarin
SeriousCyclosporineGrade B
Dual inhibition: CYP3A4 metabolism inhibition + P-gp efflux inhibition → reduced cyclosporine clearance
SeriousTacrolimusGrade C
CYP3A4 + P-gp dual inhibition; similar mechanism to cyclosporine interaction but tacrolimus has narrower therapeutic index
SeriousDigoxinGrade C
P-gp inhibition by silymarin reduces intestinal efflux and renal secretion of digoxin → elevated digoxin levels
Show 14 more
SeriousTamoxifenGrade C
CYP2D6 inhibition reduces conversion to endoxifen (primary active metabolite); reduces efficacy in breast cancer treatment
SeriousSirolimus (rapamycin)Grade C
CYP3A4 and P-gp inhibition increases sirolimus exposure
SeriousIrinotecanGrade C
UGT1A1 inhibition by silymarin reduces SN-38 glucuronidation, potentially elevating active metabolite exposure and GI/hematologic toxicity
ModerateMidazolamGrade B
CYP3A4 competitive inhibition by silybin and isosilybin; Ki ~5–15 µM
ModerateIndinavirGrade B
CYP3A4 inhibition; P-gp inhibition reduces intestinal efflux of indinavir
ModerateInsulin and sulfonylureasGrade B
Silymarin has demonstrated blood glucose-lowering effects (AMPK activation, gluconeogenesis inhibition, insulin sensitization). Additive hypoglycemic effect when combined with secretagogues or exogenous insulin.
ModerateSimvastatin / LovastatinGrade C
CYP3A4 inhibition increases statin AUC → elevated myopathy/rhabdomyolysis risk
ModerateLosartanGrade C
CYP2C9 inhibition impairs losartan → EXP3174 conversion; reduces antihypertensive efficacy
ModerateMetforminGrade C
Silymarin may inhibit OCT1/OCT2 transporters → altered metformin hepatic and renal distribution; secondary: insulin-sensitizing synergy may cause additive hypoglycemia
ModerateAntidiabetic agents (sulfonylureas: glipizide, glyburide)Grade C
CYP2C9 inhibition reduces sulfonylurea clearance; additive hypoglycemic effect from silymarin's insulin-sensitizing properties
ModerateBaicaleinGrade C
Inhibits BCRP (ABCG2) and MRP2 (ABCC2) efflux transporters; reduces intestinal efflux and biliary elimination of silibinin diastereomers
ModerateStatins (CYP3A4-metabolized: simvastatin, lovastatin, atorvastatin)Grade C
CYP3A4 inhibition reduces statin clearance. OATP1B1/1B3 competition may also reduce hepatic uptake of statin acids.
ModerateOral contraceptives (estradiol/ethinylestradiol)Grade D
CYP3A4 inhibition may increase estrogen exposure; UGT1A1 competition may reduce glucuronide conjugation of estrogens
MinorOral contraceptives / exogenous estrogensGrade D
UGT1A1 and possible SULT inhibition reduces estrogen phase II conjugation; CYP1A2 inhibition reduces estradiol metabolism.
02What it moves
29 markers studied
Read with this in mind
Disproportionate representation of Chinese, Iranian, and Eastern European study populations in the NAFLD/metabolic syndrome RCT corpus.
CONTESTED: Clinical outcome benefit in advanced cirrhosis is unproven.
CONTESTED: Bioavailability-dependent efficacy creates major comparability problem.
Blood sugar4 of 4 studied
HbA1cLowersGrade A
Milk thistle lowers HbA1c.
Meta-analysis or review · Small effect · 14 studies linked
HbA1c reduction modest and primarily demonstrated in T2DM populations with concurrent NAFLD. Unlikely to be clinically meaningful as glycemic monotherapy. Adjunctive role in metabolic liver disease; not a standalone diabetes treatment.
- Impacts of Supplementation with Silymarin on Cardiovascular Risk Factors: A Systematic Review and Dose–Response Meta-Analysis (2024)
- The effects of silymarin supplementation on metabolic status and oxidative stress in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of clinical trials (2018)
- Silymarin in Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials (2016)
- Meta-analysis of the effect of herbal supplement on glycemic control in type 2 diabetes. (2011)
- Nutraceutical composition (yeast β-glucan, prebiotics, minerals, and silymarin) predicts improvement of sleep quality and metabolic parameters: A randomized pilot study. (2024)
- Effect of silymarin on lipid profile and glycemic control in patients with type 2 diabetes mellitus (2024)
- +8 more studies
Fasting glucoseLowersGrade B
Milk thistle lowers fasting glucose.
Small to moderate effect · 0 studies linked
This result is graded, but no study is linked to it yet. Treat it as unconfirmed.
Kazazis 2014 review: 10–15% FPG reduction in T2DM RCTs with silymarin 140–200 mg TID. Multiple MAs confirm. Effect primarily in T2DM+NAFLD overlap populations — generalizability to isolated T2DM uncertain.
Fasting insulinLowersGrade B
Milk thistle lowers fasting insulin.
Small to moderate effect · 0 studies linked
This result is graded, but no study is linked to it yet. Treat it as unconfirmed.
Fasting insulin reduction demonstrated in T2DM + NAFLD RCTs. AMPK activation and reduced hepatic lipotoxicity proposed as mechanism. Mohammadi 2020 zebrafish data (zare_mehrjerdi_2024 content) suggests silibinin + metformin synergy — preclinical only, Grade C ceiling applies to that specific finding.
HOMA-IRLowersGrade A
Milk thistle lowers HOMA-IR.
Meta-analysis or review · Small to moderate effect · 10 studies linked
HOMA-IR reduction correlates with ALT reduction in NAFLD trials suggesting hepatic insulin resistance as shared driver. Effect size larger in populations with higher baseline insulin resistance. Supports metabolic hepatoprotection mechanism beyond anti-inflammatory action.
- Effects of silymarin on insulin resistance and sensitivity: A systematic review and meta-analysis of randomized controlled trials. (2025)
- Anti-Tumor Activity and Mechanism of Silibinin Based on Network Pharmacology and Experimental Verification. (2024)
- The Effects of a Fixed Combination of Berberis aristata and Silybum marianum on Dyslipidaemia - A Meta-analysis and Systematic Review. (2020)
- Lower glycemic indices and lipid profile among type 2 diabetes mellitus patients who received novel dose of Silybum marianum (L.) Gaertn. (silymarin) extract supplement: A Triple-blinded randomized co (2018)
- Bioimpedance analysis, metabolic effects and safety of the association Berberis aristata/Bilybum marianum: a 52-week double-blind, placebo-controlled study in obese patients with type 2 diabetes. (2017)
- Effects of a Combination of Berberis aristata, Silybum marianum and Monacolin on Lipid Profile in Subjects at Low Cardiovascular Risk; A Double-Blind, Randomized, Placebo-Controlled Trial. (2017)
- +4 more studies
Lipids4 of 6 studied
LDL-CLowersGrade A
Milk thistle lowers LDL-C.
Meta-analysis or review · Small effect · 20 studies linked
Approximately −0.22 SMD; −5 to −12 mg/dL. Some MAs report no significant LDL effect. Phospholipid formulations may show larger reductions. Contested (see pc_005).
- Anti-Tumor Activity and Mechanism of Silibinin Based on Network Pharmacology and Experimental Verification. (2024)
- Impacts of Supplementation with Silymarin on Cardiovascular Risk Factors: A Systematic Review and Dose–Response Meta-Analysis (2024)
- The Effects of a Fixed Combination of Berberis aristata and Silybum marianum on Dyslipidaemia - A Meta-analysis and Systematic Review. (2020)
- Metabolic effect of berberine–silymarin association: A meta‐analysis of randomized, double‐blind, placebo‐controlled clinical trials (2019)
- Effects of silymarin supplementation on blood lipids: A systematic review and meta‐analysis of clinical trials (2019)
- The effects of silymarin supplementation on metabolic status and oxidative stress in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of clinical trials (2018)
- +14 more studies
HDL-CRaisesGrade A
Milk thistle raises HDL-C.
Meta-analysis or review · Small effect · 12 studies linked
Approximately +0.18 SMD; +2 to +5 mg/dL. Not consistently significant across trials. Limited RCT data with HDL as primary outcome.
- Anti-Tumor Activity and Mechanism of Silibinin Based on Network Pharmacology and Experimental Verification. (2024)
- Impacts of Supplementation with Silymarin on Cardiovascular Risk Factors: A Systematic Review and Dose–Response Meta-Analysis (2024)
- The Effects of a Fixed Combination of Berberis aristata and Silybum marianum on Dyslipidaemia - A Meta-analysis and Systematic Review. (2020)
- Metabolic effect of berberine–silymarin association: A meta‐analysis of randomized, double‐blind, placebo‐controlled clinical trials (2019)
- Effects of silymarin supplementation on blood lipids: A systematic review and meta‐analysis of clinical trials (2019)
- The effects of silymarin supplementation on metabolic status and oxidative stress in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of clinical trials (2018)
- +6 more studies
TriglyceridesLowersGrade A
Milk thistle lowers triglycerides.
Meta-analysis or review · Small to moderate effect · 26 studies linked
Approximately −0.38 SMD; −15 to −35 mg/dL in NAFLD populations. Most significant reduction with baseline hypertriglyceridemia; null in normolipidemic populations. Contested (see pc_005).
- Anti-Tumor Activity and Mechanism of Silibinin Based on Network Pharmacology and Experimental Verification. (2024)
- Impacts of Supplementation with Silymarin on Cardiovascular Risk Factors: A Systematic Review and Dose–Response Meta-Analysis (2024)
- The Effects of a Fixed Combination of Berberis aristata and Silybum marianum on Dyslipidaemia - A Meta-analysis and Systematic Review. (2020)
- Metabolic effect of berberine–silymarin association: A meta‐analysis of randomized, double‐blind, placebo‐controlled clinical trials (2019)
- Effects of silymarin supplementation on blood lipids: A systematic review and meta‐analysis of clinical trials (2019)
- The effects of silymarin supplementation on metabolic status and oxidative stress in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of clinical trials (2018)
- +20 more studies
Total cholesterolLowersGrade A
Milk thistle lowers total cholesterol.
Meta-analysis or review · Small effect · 24 studies linked
Approximately −0.28 SMD; −8 to −18 mg/dL. Effect modest and inconsistent across trials. May be disease-specific to NAFLD (see pc_005). Contested.
- Anti-Tumor Activity and Mechanism of Silibinin Based on Network Pharmacology and Experimental Verification. (2024)
- Impacts of Supplementation with Silymarin on Cardiovascular Risk Factors: A Systematic Review and Dose–Response Meta-Analysis (2024)
- The Effects of a Fixed Combination of Berberis aristata and Silybum marianum on Dyslipidaemia - A Meta-analysis and Systematic Review. (2020)
- Metabolic effect of berberine–silymarin association: A meta‐analysis of randomized, double‐blind, placebo‐controlled clinical trials (2019)
- Effects of silymarin supplementation on blood lipids: A systematic review and meta‐analysis of clinical trials (2019)
- The effects of silymarin supplementation on metabolic status and oxidative stress in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of clinical trials (2018)
- +18 more studies
Inflammation3 of 5 studied
hs-CRPLowersGrade A
Milk thistle lowers hs-CRP.
Meta-analysis or review · Small to moderate effect · 7 studies linked
Approximately −0.38 SMD. hsCRP reduction correlates with ALT normalization in NAFLD RCTs. Effect mediated by NF-κB inhibition (mech_002). CRP in this context reflects hepatic inflammation rather than cardiovascular risk.
- Impacts of Supplementation with Silymarin on Cardiovascular Risk Factors: A Systematic Review and Dose–Response Meta-Analysis (2024)
- The effects of silymarin consumption on inflammation and oxidative stress in adults: a systematic review and meta-analysis (2024)
- Effects of Silybum marianum, Pueraria lobate, combined with Salvia miltiorrhiza tablets on non-alcoholic fatty liver disease in adults: A triple-blind, randomized, placebo-controlled clinical trial. (2024)
- Effects of a Combination of Berberis aristata, Silybum marianum and Monacolin on Lipid Profile in Subjects at Low Cardiovascular Risk; A Double-Blind, Randomized, Placebo-Controlled Trial. (2017)
- Effects of Silybum marianum (L.) Gaertn. (silymarin) extract supplementation on antioxidant status and hs-CRP in patients with type 2 diabetes mellitus: a randomized, triple-blind, placebo-controlled (2015)
- A randomized, placebo-controlled study on the effects of a nutraceutical combination of red yeast rice, silybum marianum and octasonol on lipid profile, endothelial and inflammatory parameters. (2014)
- +1 more studies
IL-6LowersGrade A
Milk thistle lowers IL-6.
Meta-analysis or review · Moderate effect · 9 studies linked
Approximately −0.52 SMD. Human IL-6 data sparser than TNF-α. Demonstrated in NASH RCTs as secondary outcome. NF-κB inhibition mechanistically links to IL-6 suppression. See pc_016 re: animal study predominance.
- The effects of silymarin consumption on inflammation and oxidative stress in adults: a systematic review and meta-analysis (2024)
- Meta-analysis: silymarin and its combination therapy for the treatment of chronic hepatitis B (2012)
- Nutraceutical composition (yeast β-glucan, prebiotics, minerals, and silymarin) predicts improvement of sleep quality and metabolic parameters: A randomized pilot study. (2024)
- A randomized trial assessing the efficacy of Silymarin on endometrioma-related manifestations (2022)
- Effects of a Combination of Berberis aristata, Silybum marianum and Monacolin on Lipid Profile in Subjects at Low Cardiovascular Risk; A Double-Blind, Randomized, Placebo-Controlled Trial. (2017)
- A randomized, placebo-controlled study on the effects of a nutraceutical combination of red yeast rice, silybum marianum and octasonol on lipid profile, endothelial and inflammatory parameters. (2014)
- +3 more studies
TNF-αLowersGrade A
Milk thistle lowers TNF-α.
Meta-analysis or review · Moderate effect · 9 studies linked
Approximately −0.65 SMD but weighted toward animal studies. 119 studies in corpus — predominantly preclinical. Human RCT data for systemic TNF-α reduction as primary endpoint is sparse. See pc_016.
- Meta-analysis: silymarin and its combination therapy for the treatment of chronic hepatitis B (2012)
- Free Radical-Scavenging, Anti-Inflammatory/Anti-Fibrotic and Hepatoprotective Actions of Taurine and Silymarin against CCl4 Induced Rat Liver Damage (2015)
- A randomized, placebo-controlled study on the effects of a nutraceutical combination of red yeast rice, silybum marianum and octasonol on lipid profile, endothelial and inflammatory parameters. (2014)
- Immunosuppressive effect of silymarin on mitogen-activated protein kinase signalling pathway: the impact on T cell proliferation and cytokine production. (2013)
- Effect of Addition of Silymarin to Renin-Angiotensin System Inhibitors on Proteinuria in Type 2 Diabetic Patients With Overt Nephropathy: A Randomized, Double-Blind, Placebo-Controlled Trial (2012)
- Evaluation of antioxidant capacity and inflammatory cytokine gene expression in horses fed silibinin complexed with phospholipid. (2013)
- +3 more studies
Liver6 of 6 studied
ALTLowersGrade A
Milk thistle lowers ALT.
74 studies linked
A-grade evidence for ALT reduction in chronic liver disease (NAFLD, chronic hepatitis). Contradicted by B-grade null finding in acute viral hepatitis (El-Kamary 2009). Population_tags reflect the chronic-disease evidence base only. Acute hepatitis use should be counselled separately.
- The therapeutic effect of silymarin in the treatment of nonalcoholic fatty disease: A meta-analysis (PRISMA) of randomized control trials. (2013)
- Effect of silymarin on biochemical indicators in patients with liver disease: Systematic review with meta-analysis. (2011)
- Prophylactic Therapy of Silymarin (Milk Thistle) on Antituberculosis Drug-Induced Liver Injury: A Meta-Analysis of Randomized Controlled Trials. (2016)
- Milk thistle for alcoholic and/or hepatitis B or C virus liver diseases. (2005)
- An updated systematic review with meta-analysis for the clinical evidence of silymarin. (2008)
- A randomized controlled trial to assess the safety and efficacy of silymarin on symptoms, signs and biomarkers of acute hepatitis. (2009)
- +68 more studies
ASTLowersGrade A
Milk thistle lowers AST.
85 studies linked
A-grade in chronic liver disease. Null in acute hepatitis context (El-Kamary 2009, B-grade). Contradiction preserved; chronic-disease grade maintained.
- The therapeutic effect of silymarin in the treatment of nonalcoholic fatty disease: A meta-analysis (PRISMA) of randomized control trials. (2013)
- Effect of silymarin on biochemical indicators in patients with liver disease: Systematic review with meta-analysis. (2011)
- Prophylactic Therapy of Silymarin (Milk Thistle) on Antituberculosis Drug-Induced Liver Injury: A Meta-Analysis of Randomized Controlled Trials. (2016)
- Milk thistle for alcoholic and/or hepatitis B or C virus liver diseases. (2005)
- An updated systematic review with meta-analysis for the clinical evidence of silymarin. (2008)
- A randomized controlled trial to assess the safety and efficacy of silymarin on symptoms, signs and biomarkers of acute hepatitis. (2009)
- +79 more studies
GGTLowersGrade A
Milk thistle lowers GGT.
Meta-analysis or review · Moderate effect · 9 studies linked
Cacciapuoti 2013 (zhong_2017 content): GGT reduction p<0.001 in 72 NAFLD patients over 6 months. GGT reflects both hepatocellular damage and oxidative stress (GGT is rate-limiting for extracellular GSH catabolism and cysteine recycling); reduction may reflect dual anti-inflammatory and antioxidant action.
- The therapeutic effect of silymarin in the treatment of nonalcoholic fatty disease: A meta-analysis (PRISMA) of randomized control trials. (2013)
- Effects of silymarin supplementation on liver and kidney functions: A systematic review and dose–response meta‐analysis (2024)
- Long-term safety and efficacy of a highly purified plant-based nutraceutical for improving clinical parameters of liver function in healthy participants: a randomized, double-blind, placebo-controlled (2025)
- Comparison of efficacy of folic acid and silymarin in the management of antiepileptic drug induced liver injury: a randomized clinical trial (2017)
- Free Radical-Scavenging, Anti-Inflammatory/Anti-Fibrotic and Hepatoprotective Actions of Taurine and Silymarin against CCl4 Induced Rat Liver Damage (2015)
- [Controlled study of the effect of silymarin on alcoholic liver disease]. (1992)
- +3 more studies
ALPNo changeGrade A
Studies of Milk thistle found no change in ALP.
Meta-analysis or review · 19 studies linked
71 studies in corpus. ALP less consistently reduced; most pronounced effect in cholestatic etiologies. In NAFLD with elevated ALP, reduction correlates with steatosis improvement. Some trials show no significant ALP effect when baseline ALP is within normal range.
- The therapeutic effect of silymarin in the treatment of nonalcoholic fatty disease: A meta-analysis (PRISMA) of randomized control trials. (2013)
- Are alterations needed in Silybum marianum (Silymarin) administration practices? A novel outlook and meta-analysis on randomized trials targeting liver injury. (2025)
- Effects of silymarin supplementation on liver and kidney functions: A systematic review and dose–response meta‐analysis (2024)
- An updated systematic review with meta-analysis for the clinical evidence of silymarin. (2008)
- Evaluation of oral silymarin formulation efficacy in prevention of doxorubicin induced hepatotoxicity in patients with non-metastatic breast cancer. (2025)
- Long-term safety and efficacy of a highly purified plant-based nutraceutical for improving clinical parameters of liver function in healthy participants: a randomized, double-blind, placebo-controlled (2025)
- +13 more studies
BilirubinLowersGrade A
Milk thistle lowers bilirubin.
Meta-analysis or review · Moderate effect · 14 studies linked
El-Kamary 2009 (RCT, n=105): indirect bilirubin significantly reduced (p=0.012) with faster clinical jaundice resolution. Effect mainly in decompensated/cholestatic populations. Choleretic mechanism (mech_012) proposed.
- Effects of silymarin supplementation on liver and kidney functions: A systematic review and dose–response meta‐analysis (2024)
- High Dose of Silymarin in Patients with Decompensated Liver Disease: A Randomized Controlled Trial (2017)
- Antiviral activity and safety profile of silibinin in HCV patients with advanced fibrosis after liver transplantation: a randomized clinical trial (2014)
- A randomized controlled trial to assess the safety and efficacy of silymarin on symptoms, signs and biomarkers of acute hepatitis. (2009)
- Silymarin, a possible hepatoprotector in dairy cows: biochemical and histological observations. (2004)
- [Liver-protective action of silymarin therapy in chronic alcoholic liver diseases]. (1989)
- +8 more studies
AlbuminRaisesGrade A
Milk thistle raises albumin.
Meta-analysis or review · Small effect · 8 studies linked
Albumin improvement mainly in decompensated cirrhosis reflecting synthetic function recovery. HALT-C (Freedman 2011) showed no significant clinical benefit in advanced HCV fibrosis. Grade C assigned — limited RCT data with albumin as primary endpoint; hepatic synthetic recovery data largely from observational studies.
- Effect of silymarin on biochemical indicators in patients with liver disease: Systematic review with meta-analysis. (2011)
- Effects of silymarin supplementation on liver and kidney functions: A systematic review and dose–response meta‐analysis (2024)
- Milk thistle for the treatment of liver disease: a systematic review and meta-analysis. (2002)
- High Dose of Silymarin in Patients with Decompensated Liver Disease: A Randomized Controlled Trial (2017)
- Effect of Addition of Silymarin to Renin-Angiotensin System Inhibitors on Proteinuria in Type 2 Diabetic Patients With Overt Nephropathy: A Randomized, Double-Blind, Placebo-Controlled Trial (2012)
- Silymarin in the Treatment of Patients with Primary Sclerosing Cholangitis: An Open-Label Pilot Study (2007)
- +2 more studies
Blood and iron2 of 7 studied
HemoglobinRaisesGrade B
Milk thistle raises hemoglobin.
Human trials · 1 study linked
26 studies mention hemoglobin but not as primary endpoint. No evidence for clinically meaningful hemoglobin effect.
FerritinLowersGrade B
Milk thistle lowers ferritin.
Human trials · Small effect · 2 studies linked
Ferritin reduction in NAFLD likely reflects reduced hepatocyte damage/inflammation rather than iron chelation. Silybin has demonstrated iron chelating properties in vitro but clinical iron overload data absent. Limited human RCT evidence specifically for ferritin as primary endpoint.
Hormones3 of 5 studied
TestosteroneChangesGrade B
Milk thistle changes testosterone.
Human trials · 3 studies linked
- Semen quality, antioxidant status and reproductive performance of rabbits bucks fed milk thistle seeds and rosemary leaves. (2017)
- Use of selenium-silymarin mix reduces lower urinary tract symptoms and prostate specific antigen in men. (2013)
- The safety and efficacy of a silymarin and selenium combination in men after radical prostatectomy - a six month placebo-controlled double-blind clinical trial. (2010)
EstradiolNo changeGrade B
Studies of Milk thistle found no change in estradiol.
Human trials · 1 study linked
8 studies mention estradiol; predominantly in vitro ERβ binding studies. No human hormonal endpoint data.
CortisolLowersGrade B
Milk thistle lowers cortisol.
Human trials · 1 study linked
3 studies; no meaningful cortisol effect data. No human hormonal endpoint RCT.
Oxidative stress4 of 4 studied
MDALowersGrade A
Milk thistle lowers MDA.
Meta-analysis or review · Moderate effect · 13 studies linked
Safarpour 2023 (rat, 5-FU GI toxicity): SMN 5mg/kg IP reduced malondialdehyde in tongue, esophagus, and intestinal tissue vs 5-FU control. Mechanistically consistent with known antioxidant activity. C-grade ceiling; human evidence absent for this specific endpoint/context.
- Safarpour S,Ramezani M,Amel Farzad S,Ramezani F (2023)
- Effects of silymarin supplementation on liver and kidney functions: A systematic review and dose–response meta‐analysis (2024)
- The effects of silymarin consumption on inflammation and oxidative stress in adults: a systematic review and meta-analysis (2024)
- The effects of silymarin supplementation on metabolic status and oxidative stress in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of clinical trials (2018)
- Adjunctive silymarin supplementation and its effects on disease severity, oxidative stress, and inflammation in patients with Alzheimer's disease. (2024)
- Antioxidative effects of silymarin on the reduction of liver complications of fingolimod in patients with relapsing-remitting multiple sclerosis: A clinical trial study. (2021)
- +7 more studies
F2-isoprostanesLowersGrade D
Milk thistle lowers F2-isoprostanes.
1 study linked
Non-significant trend only; underpowered sub-study within PK trial; no dedicated placebo arm for this endpoint; directionally consistent with antioxidant mechanism but insufficient to support efficacy claim; Grade D
8-OHdGLowersGrade C
Milk thistle lowers 8-OHdG.
Small effect · 0 studies linked
This result is graded, but no study is linked to it yet. Treat it as unconfirmed.
6 studies; predominantly animal model data. Directional decrease consistent with antioxidant mechanism (mech_001, mech_004). No adequately powered human RCT with 8-OHdG as primary endpoint.
GlutathioneRaisesGrade A
Milk thistle raises glutathione.
Meta-analysis or review · Moderate effect · 18 studies linked
138 studies — highest corpus coverage biomarker. Predominantly animal/in-vitro. Human studies use erythrocyte/plasma GSH as proxy. Nrf2/HO-1/GPx induction (mech_004) likely mediates.
- Effects of silymarin supplementation on liver and kidney functions: A systematic review and dose–response meta‐analysis (2024)
- The effects of silymarin consumption on inflammation and oxidative stress in adults: a systematic review and meta-analysis (2024)
- Hepatic fatty acids profile, oxidative stability and egg quality traits ameliorated by supplementation of alternative lipid sources and milk thistle meal. (2022)
- Effects of Silybum marianum (L.) Gaertn. (silymarin) extract supplementation on antioxidant status and hs-CRP in patients with type 2 diabetes mellitus: a randomized, triple-blind, placebo-controlled (2015)
- [Effects of the mixture of Swertia pseudochinensis Hara and Silybum marianum Gaertn extracts on CCl(4)-induced liver injury in rats with non-alcoholic fatty liver disease]. (2012)
- Combined therapy of silymarin and desferrioxamine in patients with beta-thalassemia major: a randomized double-blind clinical trial. (2009)
- +12 more studies
Minerals1 of 5 studied
CalciumChangesGrade C
Milk thistle changes calcium.
Human trials · 1 study linked
19 studies; no targeted calcium endpoint. Safety monitoring only.
Body2 of 2 studied
Blood pressureNo changeGrade A
Studies of Milk thistle found no change in blood pressure.
Meta-analysis or review · 3 studies linked
- Impacts of Supplementation with Silymarin on Cardiovascular Risk Factors: A Systematic Review and Dose–Response Meta-Analysis (2024)
- Silymarin, Olibanum, and Nettle, A Mixed Herbal Formulation in the Treatment of Type II Diabetes: A Randomized, Double-Blind, Placebo-Controlled, Clinical Trial. (2017)
- The effect of silymarin on oral nifedipine pharmacokinetics. (2007)
Weight and BMINo changeGrade A
Studies of Milk thistle found no change in weight and BMI.
Meta-analysis or review · 4 studies linked
- Impacts of Supplementation with Silymarin on Cardiovascular Risk Factors: A Systematic Review and Dose–Response Meta-Analysis (2024)
- Efficacy of silymarin-phospholipid complex in reducing the toxicity of aflatoxin B1 in broiler chicks. (2004)
- Effects of silymarin on gossypol toxicosis in divergent lines of chickens. (2010)
- Silymarin regulates the cytochrome P450 3A2 and glutathione peroxides in the liver of streptozotocin-induced diabetic rats. (2012)
Also measured13 outcomes
Outcomes these studies measured that are not on the shared panel, so they are not on the map.
Waist CircumferenceLowersGrade B
Milk thistle lowers waist Circumference.
Human trials · 3 studies linked
- Nutraceutical composition (yeast β-glucan, prebiotics, minerals, and silymarin) predicts improvement of sleep quality and metabolic parameters: A randomized pilot study. (2024)
- Novel nutraceutical supplements with yeast β-glucan, prebiotics, minerals, and (2022)
- Bioimpedance analysis, metabolic effects and safety of the association Berberis aristata/Bilybum marianum: a 52-week double-blind, placebo-controlled study in obese patients with type 2 diabetes. (2017)
Fibrosis scoreLowersGrade B
Milk thistle lowers fibrosis score.
Moderate effect · 2 studies linked
Borderline significant histologic benefit only. Effect size HR 0.57 is promising but CI upper bound = 1.00 and clinical outcome data is null. Healthy-user confounding probable in observational design. Grade B — observational, large n, multivariate adjusted.
Bilirubin indirectLowersGrade B
Milk thistle lowers bilirubin indirect.
Moderate effect · 1 study linked
El-Kamary 2009 (n=105, RCT, Egypt): indirect bilirubin significantly reduced with silymarin 420mg/day vs placebo at 4 weeks (p=0.012). Accompanied by faster resolution of dark urine (p=0.013), jaundice (p=0.02), and scleral icterus (p=0.043). Notably, this positive biliary signal occurs in the SAME study that shows ...
Hepatic collagenLowersGrade B
Milk thistle lowers hepatic collagen.
Moderate effect · 1 study linked
Secondary histologic endpoint from HALT-C. Statistically significant lower collagen content in current silymarin users across serial biopsies. Quantitative magnitude unavailable from text. Observational; confounding not fully excluded.
Hepatic steatosisLowersGrade B
Milk thistle lowers hepatic steatosis.
Moderate effect · 1 study linked
Ultrasound-measured steatosis reduction in NAFLD confirmed. Hepatorenal brightness ratio is semi-quantitative (operator-dependent) — lower precision than MRI-PDFF or controlled attenuation parameter. Histologic steatosis reduction from NASH biopsy-controlled trials less consistent. AMPK-mediated lipogenesis inhibiti...
Serum iron absorptionLowersGrade B
Milk thistle lowers serum iron absorption.
1 study linked
Effect demonstrated in fully-treated HH patients at physiological iron balance. Iron chelation maintained in presence of 124 mg ascorbic acid. Ascorbic acid normally enhances non-heme iron absorption; silybin overcomes this pro-absorptive effect. Clinically relevant to iron supplementation interaction and HFE PGx en...
Il2LowersGrade C
Milk thistle lowers Il2.
Moderate effect · 1 study linked
Safarpour 2023: SMN reduced IL-2 mRNA in GI tissues (tongue, esophagus, intestine) in 5-FU toxicity rat model. C-grade. IL-2 suppression in this context reflects anti-inflammatory mucosal protection mechanism.
INRLowersGrade C
Milk thistle lowers INR.
Small effect · 0 studies linked
This result is graded, but no study is linked to it yet. Treat it as unconfirmed.
INR/PT improvement only in advanced cirrhosis populations with synthetic dysfunction; sparse RCT data. Important clinical caveat: CYP3A4 inhibition may potentiate warfarin effect → INR elevation with concurrent anticoagulation therapy.
Show 5 more
SOD activityRaisesGrade C
Milk thistle raises SOD activity.
Moderate effect · 0 studies linked
This result is graded, but no study is linked to it yet. Treat it as unconfirmed.
SOD upregulation predominantly from animal models; human erythrocyte SOD data very sparse. Nrf2/ARE pathway (mech_004) mechanistically links silybin to SOD1/SOD2 gene induction. Extrapolation to human hepatic SOD activity requires tissue measurement — not practically measurable in clinical trials.
Ho1 expressionRaisesGrade D
Milk thistle raises Ho1 expression.
2 studies linked
Two independent in vitro sources converge on HO-1 induction; Nrf2/ARE pathway activation inferred; mechanistic confidence within D-grade ceiling is strengthened by replication; no human in vivo HO-1 data available
Pparg expressionRaisesGrade D
Milk thistle raises pparg expression.
Moderate effect · 2 studies linked
Cmyc expressionLowersGrade D
Milk thistle lowers cmyc expression.
Moderate effect · 1 study linked
Nf kb activityLowersGrade D
Milk thistle lowers nf kb activity.
1 study linked
Mechanistic detail refined: upstream IκB/RelA pathway suppression, NOT direct NF-κB DNA-binding inhibition; Grade D ceiling (in vitro Huh-7.5 cells only)
How it might work4
Proposed mechanisms. Most rest on lab and animal work, so read them as explanations, not proof of an effect.
- Direct ROS scavenging via flavonolignan electron donation - silybin B phenolic OH groups quench hydroxyl, superoxide, and peroxynitrite radicals at nanomolar concentrations in vitro
- NF-kB p65 nuclear translocation inhibition → suppression of TNF-alpha, IL-1beta, IL-6, and COX-2 transcription in hepatocytes and Kupffer cells under LPS/oxidative stimulation
- TGF-beta1/Smad2/3 signaling suppression → reduced hepatic stellate cell (HSC) activation, alpha-SMA expression, and collagen I/III synthesis → antifibrotic phenotype
- Nrf2/ARE pathway activation → nuclear Nrf2 translocation → upregulation of HO-1, NQO1, TXNRD1, AKR1C1, catalase, SOD, and GPx gene expression → secondary endogenous GSH elevation
03No result yet
29 markers
Not yet reviewed29
No study in this dossier reported these, and they haven't been searched for one by one yet.
- Inflammation
- ESRFibrinogen
- Blood and iron
- HematocritRed cellsMCVWhite cellsPlatelets
- Thyroid
- TSHFree T3Free T4Reverse T3
- B vitamins
- HomocysteineFolateVitamin B12MMA
Open questions4
- Does oral silymarin achieve sufficient intrahepatic concentrations to meaningfully activate the Nrf2/ARE pathway in human hepatocytes, given ~0.7-1.5% oral bioavailability of standard extract?
- Is silymarin effective for ALT/AST reduction in obese (BMI >=30) NAFLD patients, given the null subgroup signal from Shahsavari 2025 MA?
- What is the safety and efficacy profile of silymarin in pediatric NAFLD, which is increasing in prevalence globally?
- What is the long-term (>2 year) safety profile of continuous silymarin supplementation at standard doses?
04The studies and genetics
Go deeper
Every study and gene finding
Open the strongest papers with their populations and findings, and the gene differences human studies measured.
Compare with
- Omega-329 shared
- Zinc29 shared
- L-carnitine28 shared
- Melatonin28 shared
- Resveratrol28 shared
Each marker shows the strongest record in the dossier. Records are extracted from published studies by a model pipeline and graded A to D; records whose own notes say no usable human data exists count as no result yet. Research summaries for education, not medical advice. How this page is sourced