Silymarin (Milk Thistle), graded Moderate-evidence on Magellan — silybin constitutes roughly 70–80% of the extract and accounts for most of its biological activity. Silymarin consistently lowers liver enzymes and improves metabolic markers in NAFLD and showed a fibrosis signal in the best NASH trial, but that trial missed its primary endpoint and no study proves prevention of cirrhosis or liver-related death.
Source: Ann Hepatol 2023, PMID 38579127 ↗ · Nutraceuticals & Cellular Energizers · How Magellan grades evidence · Study write-up · evidence confidence: high
Silymarin is a mixture of flavonolignans—principally silybin (silibinin), along with silychristin, silydianin, and the flavonoid taxifolin—extracted from the fruits and seeds of milk thistle (Silybum marianum), a plant used medicinally for over two thousand years. Silybin constitutes roughly 70–80% of the extract and accounts for most of its biological activity. In laboratory and animal models, silymarin exhibits antioxidant, anti-inflammatory, antifibrotic, membrane-stabilizing, and liver-regenerating properties, and it is used chiefly as a hepatoprotective agent.
In non-alcoholic fatty liver disease (NAFLD/MASLD), multiple meta-analyses of randomized trials find that silymarin modestly lowers the liver enzymes ALT and AST and improves metabolic markers including cholesterol, triglycerides, and fasting insulin, though reviewers caution that the underlying trials are small and of variable quality. Results on harder outcomes are mixed: a rigorous biopsy-based NASH trial missed its primary histologic endpoint yet showed a fibrosis signal (22.4% vs 6.0% improvement over placebo), a landmark trial found no survival benefit in alcoholic cirrhosis, and no study demonstrates prevention of cirrhosis or liver-related death. A randomized prophylaxis trial reported less anti-tuberculosis drug-induced liver injury with milk thistle, and meta-analyses report modest reductions in fasting glucose in type 2 diabetes. Plain silymarin is poorly absorbed, a real limitation that phosphatidylcholine (phytosome) formulations partly address. This evidence describes the silymarin/milk-thistle compound and its mechanisms in general, not this specific commercial product, which has not itself been tested in the cited studies.
Peer-reviewed studies on the active compound — citations link to PubMed.
“Silymarin can regulate energy metabolism, attenuate liver damage, and improve liver histology”
“Silymarin exhibits antioxidant, lipid-lowering, antidiabetic, and hepatoprotective effects”
“Silymarin seems to be effective in reducing transaminase levels in individuals with NAFLD. Despite the statistical benefits, we call attention to potential flaws related to the quality of the included studies.”
“SIL has positive efficacy to reduce transaminases levels in NAFLD patients. SIL can be an encouraging and considerable phytotherapy for NAFLD patients.”
“Silymarin minimally reduced, but without clinical relevance, the serum levels of ALT and AST. It is necessary to carry out studies with more appropriate methodological designs.”
“We found that silymarin significantly reduced the levels of ALT (MD= -17.12 [-28.81, -4.43]), (P < 0.004), AST (MD= -12.56 [-19.02, -6.10]), (P < 0.0001) and TG (MD = -22.60 [-23.83, -21.38]) (< 0.00001).”
Research describes the active mechanism and is not a claim about this specific product.
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Yes — its active compound is linked to 18 peer-reviewed studies, summarized and cited above.
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