What the NIH says about the evidence
- NCCIH says there is not enough high-quality evidence to reach definite conclusions about milk thistle for any health condition.
- Trials for liver diseases gave conflicting or limited results. Two NIH-funded studies of silymarin found no benefit.
- A small number of studies suggest it may help control blood sugar in people with type 2 diabetes. It is unclear whether those results apply everywhere.
Safety
- Milk thistle taken by mouth appears to be well tolerated. The most common side effects are bloating, nausea and gas.
- It may cause allergic reactions, especially in people allergic to ragweed, chrysanthemum, marigold or daisy.
- NCCIH notes quality concerns: some products contained different amounts than the label said, or were contaminated.
Please note: this page is general information, not medical advice. Ask your doctor what is right for you, especially if you have a health condition or take medicine.
