According to PUBMED -- [The leading medical database for search and retrieval of biomedical and life sciences literature with the aim of improving health–both globally and personally]:
Silybum marianum or milk thistle (MT) is the most well-researched plant in the treatment of liver disease. The active complex of MT is a lipophilic extract from the seeds of the plant and is composed of three isomer flavonolignans (silybin, silydianin, and silychristin) collectively known as silymarin.
StatPearls - PUB MED NCBI
Milk thistle has been used for hundreds of years by herbalists and clinicians alike to treat a wide range of liver pathology.
Medical Studies Silybum marianum supports hormonal balance. It is one of the best plants for liver health. Liver health is vital for hormonal balance. The liver helps to filter toxins from the body, including excess hormones. It is also commonly called Milk Thistle because of its milky sap. Traditionally it is associated with increasing breast milk production, which may be another reason for its name.
Liver Cleansing and Renewal
The plant part used is the seed. Milk Thistle Seed Extract is part of our Fertility Cleanse Kits for both women and men. It is part of these kits because Milk Thistle Seed’s stimulate the liver to cleanse itself, while also stimulating it to renew liver cells. Milk Thistle seeds also stimulate the liver and gallbladder to secrete bile, aiding in digestion. Milk Thistle is the most protective plant for liver health! In fact, it is so protective of liver health, it is used to save people from Death Cap mushroom poisoning. It is also used to heal and protect the livers of people who have undergone chemotherapy.
The liver is our chemical processing plant. So you can imagine what must go on in there. The liver removes hormones, drugs, and other biologically active molecules from the blood. It then converts these by changing their structure or inactivating them, through different processes, and then excretes these to be passed through the kidneys. If there are too many excess toxins and hormones overwhelming the liver, they may be stored up, not only in the liver, but other parts of our body. Milk Thistle gives our liver the support and renewal it needs to function at its best!
Silymarin in Milk Thistle Protects the Liver
Silymarin is the main constituent in Milk Thistle that protects liver health. This is only one constituent (part, or chemical compound) found in Milk Thistle. Some people believe that your Milk Thistle product should have at least 420mg of Silymarin to be effective. Unless your product has gone through a processing plant that has scientific researchers testing each batch for chemical constituents in the plant, and then reporting that to the company to put on a label, there is no way to determine how much Silymarin is in each tablet. As an herbalist, my personal opinion on this is that Milk Thistle seeds are best taken in a tincture form (liquid extract), like the one we sell in our Natural Fertility Shop. Milk Thistle seeds are very hard, and hard to digest in capsule or tablet form. Grain Alcohol is the best way to extract the medicinal properties, including Silymarin in Milk Thistle.
There have been some studies on Silymarin in Milk Thistle. These were performed to see why Milk Thistle was helpful to the liver; they found that Silymarin was the main part of the plant that aids the liver in cleansing and regeneration.
Studies in the German Journal of Medicinal Plant Research, Planta Med., found that Milk Thistle combats oxidative stress and increases glutathione content (enhancing detoxification) throughout the digestive tract, including the liver. Glutathione is a key antioxidant, “nature’s master antioxidant and detoxifier”, for the liver. Researchers at the Department of Gastroenterology, Cisanello Hospital, Pisa, Italy, report evidence from experimental research and clinical studies that glutathione holds promise for those needing to recover from oxidative stress-induced liver damage.
Researchers from Alagappa University in India have found based on their work that “The antioxidant and free radical scavenging activity of flavonoids like silymarin… novel therapeutic strategies against environmental contaminant exposure.”
The Liver-protecting properties of Milk Thistle in part stem from the flavonid silibinin, which has been found to boost the activity of Kupffer cells (liver cells important in the liver’s response to pathogens). Kupffer cells are known inhibit the inflammatory molecules called leukotrienes, and are “critical mediators of both liver injury and repair.” (Journal: Hepatology)
Findings like these popularized Silymarin and many products are now sold with this name, rather than by Milk Thistle. Personally, I feel that using a whole plant part ensures you are receiving the wide variety of medicinal benefits from the plant, rather than isolating one part of it.
Source: multiple medical journals, research, reports articles, publications -- European & International medical data -- Natural Fertility Info publication