From the Guidelines
Milk thistle, specifically its extract silymarin, may improve liver enzymes, but its effectiveness in treating liver conditions like cirrhosis, hepatitis, and fatty liver disease is not well established due to limited and low-quality evidence. The use of milk thistle supplements is common for supporting liver health and function, with silymarin possessing antioxidant and anti-inflammatory properties that may protect liver cells from damage and promote regeneration 1.
Key Points to Consider
- The typical dosage of silymarin ranges from 140-800 mg per day, divided into 2-3 doses.
- Milk thistle is generally considered safe for most people, but it may interact with certain medications processed by the liver, such as cholesterol medications, anti-anxiety drugs, and certain cancer treatments.
- Side effects are usually mild and may include digestive upset, allergic reactions, or a potential laxative effect at higher doses.
- Individuals with hormone-sensitive conditions should use milk thistle cautiously due to its potential mild estrogenic effects.
Clinical Recommendations
- Always consult with a healthcare provider before starting milk thistle, especially if you take other medications or have existing health conditions.
- The decision to use milk thistle should be based on individual health needs and under the guidance of a healthcare professional, considering the current lack of strong evidence supporting its effectiveness for liver conditions 1.
- Given the limited evidence, it is crucial to prioritize established treatments for liver conditions and use milk thistle only under medical supervision.
From the Research
Effects of Silybum marianum (Milk Thistle)
- Silybum marianum, also known as milk thistle, is an herbal supplement used to treat liver and biliary disorders 2.
- The active component of milk thistle, silymarin, protects liver and kidney cells from toxic effects of drugs, including chemotherapy, and has anti-inflammatory and T cell-modulating effects 2, 3.
- Silymarin has been shown to have hepatoprotective and anticarcinogenic effects, including inhibition of cancer cell growth in human prostate, skin, breast, and cervical cells 2, 4.
Mechanisms of Action
- Silymarin acts as an antioxidant by reducing free radical production and lipid peroxidation, and has antifibrotic activity 3.
- Silymarin may act as a toxin blockade agent by inhibiting binding of toxins to the hepatocyte cell membrane receptors 3.
- Silybin, a component of silymarin, has the greatest degree of biological activity and makes up 50% to 70% of silymarin 3.
Clinical Uses
- Milk thistle has been used to treat alcoholic liver disease, acute and chronic viral hepatitis, and toxin-induced liver diseases 3, 5.
- Silymarin has been shown to reduce liver enzyme levels and demonstrate anti-inflammatory and T cell-modulating effects 2.
- However, the results of clinical trials on the effectiveness of milk thistle for patients with alcoholic and/or hepatitis B or C virus liver diseases are inconsistent, and high-quality evidence is lacking 6.
Safety and Adverse Events
- Milk thistle is considered safe and well-tolerated, with gastrointestinal upset, a mild laxative effect, and rare allergic reaction being the only adverse events reported when taken within the recommended dose range 2.
- Silymarin has been safely used for centuries to treat liver ailments, with few side effects reported 5.