Supports liver health
One of the most common uses of milk thistle is to treat liver problems. A 2016 study found that milk thistle improved diet-induced liver damage in mice. More evidence is needed to prove that milk thistle benefits human livers in the same way.

However, researchers theorize that it does. The active ingredient in milk thistle, silymarin, acts as an antioxidant by reducing free radical production. Scientists think this creates a detoxifying effect, which is why it is milk thistle may be beneficial for liver problems.

Until more research is carried out, however, milk thistle is not recommended as the primary treatment option for liver problems. But it may be a helpful complementary treatment to try.

Promotes skin health
Milk thistle oil may be used topically to improve skin health.
Milk thistle may help to promote healthy skin. A 2015 study found that milk thistle helped improve inflammatory skin conditions when applied to the skin of mice.

Milk thistle was also found to have antioxidant and anti-aging effects on human skin cells in a laboratory environment in another study.

Further research on humans is needed to identify what benefits a person can expect from applying milk thistle to their skin.