Milk Thistle
Also known as: Silymarin, Silybum marianum
Milk thistle (silymarin) is one of the most common herbal supplements, usually discussed around liver wellness. Despite its popularity, research results for liver conditions are conflicting or too limited to draw conclusions, and well-run studies have shown no benefit. Some small studies discuss effects on blood-sugar control, which is mainly relevant as a caution for people on diabetes medication. Product quality varies: some products differ substantially from their labels or carry contamination concerns.
Snapshot
What this page can tell you: NCCIH's framing of milk thistle's conflicting/limited liver evidence and the product-quality concerns.
What it cannot: That milk thistle treats liver disease or any condition — NCCIH's liver evidence is conflicting or too limited. Informational only.
🧩 Stack insights — how this fits into a schedule
Liver evidence / quality — NCCIH: liver-related results for milk thistle (silymarin) are conflicting or too limited to draw conclusions, including null NCCIH-funded studies. Product quality varies (label accuracy, contamination). If you take diabetes medication, review it first.
Relationship insights are informational only — they describe what is commonly discussed or studied, not what you should take. Not medical advice; review your routine with a clinician or pharmacist.
🕒 Timing
When: With a meal
Food: With food
Commonly taken with food; timing is otherwise flexible.
💊 Common use range
140–420 (silymarin, divided) mg
No established upper limit; silymarin content varies by product — follow product guidance.
Ranges are informational, not a recommended dose. Talk to a professional about what is right for you.
🤔 Worth considering?
Evidence vs. effort: Limited evidence relative to burden
Popularly framed as a liver supplement, but the liver evidence is weak or conflicting. Product quality is a real concern (label accuracy, contamination), and the blood-sugar discussion means people on diabetes medication should ask first.
A general summary, not a recommendation. Whether something fits your situation is worth discussing with a healthcare professional.
⚠️ Commonly noted interactions (supplements)
None listed.
Often about absorption or timing rather than danger — separating doses is common. This list is not exhaustive.
🧭 Caution level
Ask a clinician or pharmacist before use.
- Blood-sugar / glucose-lowering caution category
- Pregnancy / breastfeeding caution
- Glucose-lowering / diabetes medication interaction
Caution level is an informational summary of commonly discussed caution categories and doses — not a safety rating, approval, or medical advice. Low caution does not mean safe for you.
🩺 Medication caution categories
- Diabetes medication
- Pregnancy or nursing (health condition)
🏥 Surgery & procedure caution
Because it appears in blood-sugar discussions, mention it when reviewing your supplement list before any scheduled procedure.
If you have a procedure scheduled, bring your full supplement list to your surgical and anesthesia team. Do not stop prescribed medication unless your clinician tells you to. Do not start or stop supplements based only on this app.
✅ Quality checklist
- Prefer products with third-party testing or a certificate of analysis (COA) — commonly recommended for this ingredient.
- Commonly discussed quality checks: Label accuracy, Adulteration, Microbial contamination.
- Check the label for the exact form and the elemental or active amount per serving.
🧩 Commonly paired with
None listed.
🔁 Alternatives
None listed.
🗣️ Questions for a professional
- I take diabetes medication — does milk thistle change anything I should watch for?
🛡️ Safety notes (source-reviewed)
- Common side effects: bloating, nausea, gas.
- May trigger reactions in people allergic to the ragweed/daisy family.
- If you take diabetes medication, review it first (blood-sugar discussions).
⚖️ Evidence limitations
- NCCIH: liver results are conflicting or too limited for conclusions, including null NCCIH-funded studies; product quality varies.
❓ Frequently asked
Does milk thistle repair or protect the liver?
NCCIH says liver-related results are conflicting or too limited to draw conclusions, and well-run studies showed no benefit. This page makes no treatment claim.
🔬 Evidence snapshot
Liver-related results are conflicting or too limited for conclusions, including NCCIH-funded studies showing no benefit from silymarin. Small studies suggest possible effects on blood-sugar control in type 2 diabetes, with unclear generalizability.
🚦 Commonly noted cautions (auto)
Pregnancy / nursing caution category. This item carries a pregnancy/nursing caution category. If you are pregnant, nursing, or planning pregnancy, consider discussing it with a healthcare professional. This is a general caution, not a diagnosis or medical instruction.
🧪 Forms & quality
Source type: Botanical
Some products contain silymarin amounts that differ substantially from their labels, or carry pesticide, microbial, or mycotoxin contamination — third-party testing is commonly recommended.
See the supplement glossary for what form names like "L-", chelated, or standardized extract mean.
📏 Dose & monitoring
Evidence vs. burden: Limited evidence relative to burden
😐 Commonly reported side effects
- Bloating, nausea, or gas
- Allergic reactions in people sensitive to the ragweed/daisy family
Non-exhaustive and individual.
🔄 Cycling & breaks
No established cycling pattern.
📅 Daily use notes
If you take diabetes medication, ask a professional before adding milk thistle. People with ragweed, chrysanthemum, marigold, or daisy allergies may react to it.
📋 Source review status
Source-reviewed — last reviewed 2026-07-03
Reviewed against the NCCIH milk thistle page; editorial pass still pending.
Research backlog (queries to verify):
- silymarin liver disease randomized trial outcomes
- milk thistle supplement label accuracy contamination
📚 References
- NCCIH — Milk ThistleNCCIH — Verified conflicting/limited liver evidence (incl. null NCCIH-funded silymarin studies), small type-2-diabetes blood-sugar studies, GI side effects, ragweed-family allergy caution, label-accuracy/contamination concerns, and limited pregnancy data.
Verified against the source shown. See the research-status page for how review works.
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