Also indexed as:Carduus marianus, Holy Thistle, Marian Thistle, Marythistle, Silybum marianum, Silymarin, St. Mary’s Thistle, Thistle
Health information provided by Aisle7
Common names:
Holy Thistle, Marian Thistle, Marythistle, Silymarin, St. Mary’s Thistle, Thistle
Botanical names:
Carduus marianus, Silybum marianum
Parts Used & Where Grown
Milk thistle is commonly found growing wild in a variety of settings, including roadsides. The dried fruit (also called achenes) are used to produce modern herbal extracts.
How It Works
The dried fruit of milk thistle contain a flavonoid complex known as silymarin. This constituent is responsible for the medical benefits of the plant.1 Silymarin is made up of three parts: silibinin, silidianin, and silicristin. Silibinin is the most active and is largely responsible for the benefits attributed to silymarin.2
Milk thistle extract may protect the cells of the liver by blocking the entrance of harmful toxins and helping remove these toxins from the liver cells.3, 4 As with other bioflavonoids, silymarin is a powerful antioxidant.5 Silymarin has also been shown to regenerate injured liver cells.6 Recent studies have shown that silymarin has the ability to block fibrosis, a process that contributes to the eventual development of cirrhosis in people with inflammatory liver conditions secondary to diseases such as alcohol abuse or hepatitis.7
Milk thistle extract is most commonly recommended to counteract the harmful actions of alcohol on the liver. Double-blind trials indicate that it helps the liver return to a healthy state once a person stops drinking.8, 9 Some trials suggest it may improve quality of life and even life expectancy in people with liver cirrhosis.10, 11 However, another trial found no effect in cirrhosis patients.12 Milk thistle alters bile makeup, thereby potentially reducing risk of gallstones.13 However, this needs to be verified by human clinical trials. Milk thistle extract has been shown to protect the liver from the potentially damaging effect of drugs used to treat schizophrenia and other forms of psychosis.14 However, one trial found that it did not protect the liver from the potentially harmful effects of the drug Cognex (tacrine hydrochloride) used to treat early-stage Alzheimer’s disease. 15
How to Use It
For liver disease and impaired liver function, research suggests the use of 420–600 mg of silymarin per day from an herbal extract of milk thistle standardized to 80% silymarin content.16 According to research and clinical experience, improvement should be noted in about eight to twelve weeks. For people with chronic liver disease, milk thistle extract may be considered a long-term therapy.
For those who prefer, 12–15 grams of milk thistle dried fruits can be ground and eaten or made into a tea. This should not be considered therapeutic for conditions of the liver, however.
Interactions with Supplements, Foods, & Other Compounds
At the time of writing, there were no well-known supplement or food interactions with this supplement.
Interactions with Medicines
Certain medicines interact with this supplement.
 | Some medicines may increase the need for this supplement. |
|---|
 | Some medicines interact with this supplement, so they should not be taken together. |
|---|
 | Some interactions between this supplement and certain medicines require more explanation. Click the link to see details. |
|---|
Side Effects
Milk thistle extract is virtually devoid of any side effects and may be used by most people, including pregnant and breast-feeding women. In fact, it has been recommended as a treatment for itching due to poor gallbladder function during pregnancy.17 Since silymarin stimulates liver and gallbladder activity, it may have a mild, transient laxative effect in some people. This will usually cease within two to three days.
There is one case report of a 57-year-old Australian woman experiencing several episodes of nausea, abdominal pain, vomiting and weakness after taking a milk thistle preparation.18 This case is so atypical, however, that the Adverse Drug Reactions Advisory Committee of Australia questioned whether the product taken might not have contained other herbs or additives that could be responsible for the adverse reaction.
Copyright © 2012 Aisle7. All rights reserved. Aisle7.com
Learn more about Aisle7, the company.
Learn more about the authors of Aisle7 products.
The information presented in Aisle7 is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires June 2013.
