Botanical
Milk Thistle (Silymarin)
Also known as: Silybum marianum, Silymarin, Silybin, Milk Thistle Extract (Silybum marianum)
Milk thistle extract contains silymarin, a flavonoid complex traditionally used to support liver health and function. Clinical evidence suggests modest benefits for liver support, though results remain mixed across studies.
Last reviewed June 2026 · Evidence graded from peer-reviewed research, not editorial opinion. Educational only — not medical advice.
Every Milk Thistle (Silymarin) product we have scored
| # | Product | Score | Per serving |
|---|---|---|---|
| 1 | Thorne Milk Thistle Phytosome | 96 A | $0.53 |
| 2 | Thorne S.A.T.® | 94 A | $0.78 |
| 3 | Nutricost Milk Thistle Capsules | 91 A | $0.07 |
| 4 | Thorne Liver Cleanse | 90 A | $0.45 |
| 5 | Micro Ingredients Organic Milk Thistle Powder | 90 A | $0.06 |
| 6 | Life Extension Advanced Milk Thistle | 88 A | $0.60 |
| 7 | Pure Encapsulations Silymarin | 87 A | $0.38 |
| 8 | Thorne MediClear-SGS™ - Vanilla | 86 A- | $2.10 |
| 9 | Pure Encapsulations SP Ultimate | 84 A- | $2.23 |
| 10 | Jarrow Formulas Milk Thistle | 84 A- | $0.36 |
| 11 | Vital Nutrients Milk Thistle Extract 250mg | 84 A- | $1.00 |
| 12 | Pure Encapsulations UltraDetox 10-Day Pure Pack | 83 A- | $7.55 |
Scored on dose accuracy, form, label transparency and third-party testing. Per-serving cost is list price divided by servings per container. No brand pays to be listed or ranked.
Common questions
How much Milk Thistle (Silymarin) should I take?
The typical range is 200-400mg standardized extract 2-3x daily. Long-term use safe and appropriate
When should I take Milk Thistle (Silymarin)?
With meals. Yes, enhances absorption.
Which form of Milk Thistle (Silymarin) is best?
Standardized extract 70-80% silymarin — Most studied. Other forms in the catalog: Phytosome (silybin-PC), Seed extract, Powder, Capsule, Tablet, Liquid extract, Standardized extract.
Is Milk Thistle (Silymarin) safe?
Commonly reported: Rare: mild GI upset, Allergic reactions (ragweed family). Serious warnings: May affect estrogen-related conditions. Safe - specifically for liver support
Which Milk Thistle (Silymarin) supplement scores highest?
Thorne Milk Thistle Phytosome, at 96/100. Scored on dose accuracy, form, label transparency and third-party testing — no brand pays to be listed or ranked.
Primary uses
- Liver protection
- Liver regeneration
- Toxin exposure
- Alcohol support
- Liver health support
- Hepatic function
- Antioxidant support
- Liver detoxification
What systematic reviews concluded
Outcomes that systematic reviews of Milk Thistle (Silymarin) reached a verdict on: 1 with a benefit, 1 with no effect, 1 with harm reported, 2 unclear. Each is quoted from a review and linked to it on PubMed. How these were read.
Reviews found a benefit (1)
“Silymarin can regulate energy metabolism, attenuate liver damage, and improve liver histology in NAFLD patients.” PMID 38579127
Reviews found no effect (1)
“Silymarin minimally reduced, but without clinical relevance, the serum levels of ALT and AST.” PMID 28785154 · 2 reviews
Harm reported (1)
“Calcium carbonate, ferrous fumarate, some forms of ginkgo, some forms of garlic, some forms of milk thistle, St. John's wort, vitamin C, zinc sulfate, and multivitamins were all found to significantly decrease the levels of selected antiretrovirals and should be avoided in patients taking these antiretrovirals.” PMID 27655839
Not enough to say: glycemic control in type 2 diabetes; ocd symptoms.
1 finding from reviews in specific patient groups (such as cancer, pregnancy or surgery) is not shown here.
How it works
- Protects liver cell membranes
- Stimulates protein synthesis for regeneration
- Antioxidant in liver tissue
- May help with insulin sensitivity
Dosage
- Typical range
- 200-400mg standardized extract 2-3x daily
- Timing
- With meals
- With food
- Yes, enhances absorption
- Duration
- Long-term use safe and appropriate
- Special populations
- Those with liver concerns, alcohol users, medication users
Forms
- Standardized extract 70-80% silymarin
- Phytosome (silybin-PC)
- Seed extract
- Powder· 70/100
- Capsule· 70/100
- Tablet· 70/100
- Liquid extract· 70/100
- Standardized extract· 70/100
Safety
Common side effects
- Rare: mild GI upset
- Allergic reactions (ragweed family)
Contraindications
- Ragweed/daisy allergy
Products containing Milk Thistle (Silymarin)
Top-scoring supplements in our catalog that list Milk Thistle (Silymarin) on the label. Each product is graded on Formulate's ingredient-level rubric — dose accuracy, form, transparency, and third-party testing.
Evidence notes
Strong evidence for liver protection
Grade A: Multiple well-designed human trials support the main claims.
Cited research for Milk Thistle (Silymarin)
Clinical studies referenced across Formulate guides that mention milk thistle (silymarin). Each links to the full study page with PubMed source + the guides that cite it.
- Loguercio C, Andreone P, Brisc C, et al. (2012)Free Radical Biology and Medicine
Silybin combined with phosphatidylcholine and vitamin E in patients with nonalcoholic fatty liver disease
- Rambaldi A, Jacobs BP, Gluud C (2007)Cochrane Database of Systematic Reviews
Silymarin for the treatment of acute clinical hepatitis: a meta-analysis of randomized controlled trials
Milk Thistle (Silymarin) compared head-to-head
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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider. Individual needs and risks vary — consult a professional before starting, stopping, or combining supplements, especially if you are pregnant or nursing, taking medication, or managing a health condition.