Nature's Answer Milk Thistle Seed Extract Description: 80% Silymarin Promotes Healthy Liver Function Standardized Herbal Supplement Milk Thistle (Silybum marianum) has a long history of use. Although commonly referred to as a "seed," the plant part used is actually the "fruit." Recent studies have demonstrated the positive role of Milk Thistle extract and more specifically, one of its main active constituents, silymarin, in supporting and protecting the liver. Free Of Synthetic ingredients. Disclaimer These statements have not been evaluated by the FDA. These products are not intended to diagnose, treat, cure, or prevent any disease.