From the Guidelines
Milk thistle, specifically silymarin, may improve liver enzymes but has not been shown to provide histological improvement in liver disease, and its use should be approached with caution. When considering the use of milk thistle, it is essential to weigh the potential benefits against the lack of robust evidence supporting its effectiveness. According to the most recent guidelines, such as those outlined in the 2024 EASL-EASD-EASO clinical practice guidelines on the management of metabolic dysfunction-associated steatotic liver disease (MASLD) 1, the efficacy of silymarin for treating liver conditions like MASH cannot be established due to the absence of large randomized controlled trials (RCTs) with histological endpoints. Key points to consider include:
- The potential for milk thistle to improve liver enzymes, as noted in small RCTs 1
- The lack of evidence for histological improvement in liver disease
- The need for caution when using milk thistle, especially in patients taking medications that are processed by the liver
- The importance of consulting with healthcare providers before starting milk thistle, particularly for pregnant or breastfeeding women due to insufficient safety data. Given the current state of evidence, the decision to use milk thistle should be made on a case-by-case basis, prioritizing the individual's overall health status and potential risks.
From the Research
Milk Thistle Overview
- Milk thistle (Silybum marianum) is an herbal supplement used to treat liver and biliary disorders 2
- The active component, silymarin, protects liver and kidney cells from toxic effects of drugs, including chemotherapy 2
- Milk thistle has reduced liver enzyme levels and demonstrated anti-inflammatory and T cell-modulating effects 2
Clinical Efficacy and Safety
- Silymarin has metabolic and cell-regulating effects, including carrier-mediated regulation of cell membrane permeability and inhibition of the 5-lipoxygenase pathway 3
- Pooled data from case record studies show a highly significant difference in mortality in favor of silibinin (the main isomer contained in silymarin) in patients with Amanita phalloides poisoning 3
- Silymarin may be of use as an adjuvant in the therapy of alcoholic liver disease, with improved clinical tolerance and histological findings 3
- Silymarin has a good safety record, with rare case reports of gastrointestinal disturbances and allergic skin rashes 3
Therapeutic Potential
- Silymarin exhibits several beneficial properties for use in the treatment and prevention of different types of pathologies and disorders, including cancer, diabetes, hepatitis, and cardiovascular diseases 4
- Silymarin has antioxidant and anti-inflammatory effects, and acts as a modulator of signaling pathways 4
- Milk thistle extracts have been used to protect the liver against toxins and to control chronic liver diseases, with promising results in certain types of cancer 5
- Milk thistle extracts are known to be safe and well tolerated, with minimal toxic or adverse effects observed in clinical trials 5
Chemistry and Pharmacology
- Milk thistle fruits contain a mixture of flavonolignans collectively known as silymarin, with silybin (also named silibinin) as the main component 6
- Silymarin has pharmacologically relevant actions for liver diseases, including anti-inflammatory, immunomodulating, antifibrotic, antioxidant, and liver-regenerating properties 6
- Further well-designed randomized clinical trials are needed to fully substantiate the real value of milk thistle preparations in liver diseases 6