Milk thistle

Nutrient group: plant extracts & active ingredients

Sources and physiological effects

Dietary sources
Milk thistle is mainly found in the Mediterranean region, but can also be found in the west and southwest of the USA as well as in the Canary Islands and the Azores. This „liver plant“ has been used for over 2000 years in traditional herbal medicine, for example in tea form.
Physiological effects
Liver metabolism	Prevention of penetration of toxic substances into hepatocytes
Immune system	Activation of the immune system Suppression of inflammatory reactions Inhibition of virus uptake into the cell by inhibition of clathrin-mediated endocytosis

Detailed information

Milk thistle with liver-protective silymarin

Milk thistle extract (Silbybum fructus) is a potent substrate for use in liver disease. The active component, silymarin, was evaluated positively in clinical studies, especially in chronic inflammatory, toxic and alcohol-related liver diseases and in liver cirrhoses (1). Silymarin showed strong anti-inflammatory effects in hepatitis patients (2). Liver-protective and immunomodulating activities have been demonstrated (3) as well as an improvement in general symptoms and liver enzyme values (1). Silymarin can prevent the penetration of toxic compounds into hepatocytes by binding to membrane proteins. In addition, the protein synthesis rate and thus the ability of healthy liver cells to regenerate is increased and the repair of excisting cellular-structural damage is promoted (1).

Milk thistle – studies confirm efficacy in infectious diseases

Silibinin, the major component of silymarin, inhibits clathrin-mediated endocytosis. This is the way in which the hepatitis C virus is introduced into the liver cells. Other viruses that use this gateway are also inhibited by Silymarin (4) (5).
For example, it has been shown that silibinin can also prevent the replication of HIV-1 in T-cells. Silibinin also suppresses cell growth of certain T cells (CD4⁺) that carry a receptor that makes them particularly susceptible to HIV. The cell-protective properties of milk thistle extract are probably due to the fact that it suppresses the activation of the immune system and inflammatory reactions in addition to viral infections (6).

Indications

Effect	Indication	Dosage
Physiological effects at a low intake	Prevention of liver damage and for liver support	150 mg/d
	Complementary therapy for chronic inflammatory liver diseases	300 – 450 mg/d
	Complementary therapy for liver parenchyma changes	300 – 450 mg/d
	To support liver metabolism and improvement of liver regeneration	300 – 450 mg/d

Administration

General mode of administration
When	Milk thistle extract should be taken between or before meals.
Side effects
No side effects are known to date.
Contraindications
No contraindications are known to date.

Interactions

Drug interactions
Analgesics, antiepileptics, Tuberculosis drugs, tricyclic antidepressants, neuroleptics	Silymarin or milk thistle extract reduces the hepatotoxic properties of these drugs when taken simultaneously.
Insulin	Simultaneous use may reduce the dose of insulin in type 1 diabetics.
Nutrient interactions
None	No relevant interactions are known to date.

References

1) Wagner, H., Wiesenauer, M.Phytotherapie. Phytopharmaka und pflanzliche Homöopathika. 2003.
2) El-Zayadi, A. M. et al. 2005. Non-interferon-based therapy: an option for amelioration of necro-inflammation in hepatitis C patients who cannot afford interferon therapy. Liver Int. 25(4):746-51.
3) Deak, G. et al. 1990. Immunomodulatory effect of silymarin therapy in chronic liver diseases. Orv Hetil. 131(24):1291-2.
4) Blaising, J. et al. 2013. Silibinin inhibits hepatitis C virus entry into hepatocytes by hindering clathrin-dependent trafficking. Cell Microbiol. 15(11):1866-82.
5) Ripoli, M. et al. 2016. Phytoliposome-Based Silibinin Delivery System as a Promising Strategy to Prevent Hepatitis C Virus Infection. Journal of Biomedical Nanotechnology J Biomed Nanotechnol. 12(4):770-780.
6) McClure, J. et al. 2012. Silibinin inhibits HIV-1 infection by reducing cellular activation and proliferation. PLoS One. 7(7):e41832.

References Interactions
Stargrove, M. B. et al. Herb, Nutrient and Drug Interactions: Clinical Implications and Therapeutic Strategies, 1. Auflage. St. Louis, Missouri: Elsevier Health Sciences, 2008.
Gröber, U. Mikronährstoffe: Metabolic Tuning –Prävention –Therapie, 3. Auflage. Stuttgart: WVG Wissenschaftliche Verlagsgesellschaft Stuttgart, 2011.
Gröber, U. Arzneimittel und Mikronährstoffe: Medikationsorientierte Supplementierung, 3. aktualisierte und erweiterte Auflage. Stuttgart: WVG Wissenschaftliche Verlagsgesellschaft Stuttgart, 2014.