Silybum marianum
Milk Thistle
Asteraceae
At a Glance
- Common name
- Milk Thistle
- Scientific name
- Silybum marianum
- Family
- Asteraceae
- Region
- Mediterranean
- Plant part
- Seeds
- Caffeine
- Caffeine Free
- Evidence
- Moderate
- Safety review
- Safety information on file
Safety & Cautions
Safety information on fileBotanical Description
A tall thistle with large glossy dark green leaves marbled with white veins, and a large round reddish-purple thistle flower head with spiny bracts; the small dark seeds are the part used, rich in silymarin.
Also known as: Silymarin Herb, St. Mary's Thistle, Carduus marianus
Historical Background
Milk thistle has been a revered liver herb of European and Mediterranean medicine for over 2,000 years, its white-veined leaves said to mark the milk of the Virgin Mary. Its seeds, rich in silymarin, brew a mild tea long associated with liver traditions.
Earliest recorded uses: Used in European and Mediterranean medicine for over 2,000 years; a revered liver herb since Pliny and Dioscorides.
Traditional preparations:
- Crushed-seed decoction
- Liver-support tea with artichoke
- Digestive bitter blend
Traditional Uses
These uses document historical traditions and do not imply proven effectiveness.
Traditional European Herbalism
Revered liver and biliary herb since antiquity.
Modern Herbalism
Liver-support and antioxidant seed tea.
Flavor & Aroma
Aroma: Mild, slightly nutty, earthy, green
Tea Preparation
Modern Evidence
Milk thistle (silymarin) has moderate evidence from trials for some liver conditions, though results vary and quality is mixed. It is not a treatment for hepatitis, cirrhosis, NAFLD, or any disease, and should be discussed with a clinician, especially with liver or diabetes medications.
Evidence levels describe the state of research for the traditional use discussed here, not a recommendation. Historical use does not imply effectiveness.
Related Herbs
Entry last updated August 4, 2026