Independent supplement research
Milk Thistle & Silymarin: What the Liver Evidence Shows
Milk thistle has a long history of liver-related use, but historical use and modern marketing are not the same as proven clinical benefit.
What NCCIH concludes
NCCIH says there is not enough high-quality evidence for definite conclusions about milk thistle’s effects on health conditions. Clinical trials for liver diseases have been conflicting or too limited, and two NCCIH-funded studies did not show benefit for the conditions studied.
Safety
Oral milk thistle appears generally well tolerated; digestive symptoms such as bloating, nausea and gas are among the most common side effects. Allergic reactions are possible, and medicine interactions should be discussed with a health care provider.
Product-level inference
The presence of silymarin in a formula does not prove that the formula “detoxifies” or repairs the liver. Read our claims-vs-evidence framework.