Throughout history, people have used the fruit and seeds of the milk thistle plant as a treatment for liver disorders. The plant goes by several other names, including Holy thistle, Mary thistle, Our Lady's thistle, wild artichoke and St. Mary thistle. Traditionally, the leaves have been harvested to use in salads and the flower may be roasted and used as a coffee substitute. However, it is the seeds of the milk thistle that were prized for their medicinal activity.