Milk Thistle, also known as Silybum Marianum, is a species of plant of the Asteraceae family. Both in vitro and animal research suggest that Silibinin (silymarin) may have hepatoprotective (antihepatotoxic) properties that protect liver cells against toxins. Our product is a 4:1 ethanol extract, which provides concentrated amounts of the active ingredient silymarin. Others on the market are either not an extract, or use more volatile solvents in the extraction process. Using ethanol to create a 4:1 extract is not the cheapest method, but leads to the highest quality product.