Silybin is another term for silibinin. Silybin is one of a group of flavonolignans collectively referred to as silymarin, which is extracted from the milk thistle plant (Silybum marianum).
Silymarin has demonstrated a diverse array of medicinal properties and is one of the most prescribed natural substances. It is also one of the most demanded natural healthcare products among supplement users. Silybin is the most prevalent substance in silymarin, and the terms “silybin” and “silymarin” are often used interchangeably, along with the term “milk thistle” itself.
Milk thistle has been used as a food and a medicine since ancient times. As a medicinal treatment it was primarily used to treat issues with the liver and/or gallbladder.
Clinical research has shown silybin extracts from milk thistle to be effective at helping the liver heal from damages incurred from alcohol, drugs, prescription medications, environmental toxins, heavy metal trace elements and other toxic substances.
Silybin Phytosome, silymarin and milk thistle supplements are being investigated as a possible adjunct therapy in the treatment of cancer, diabetes, heart disease, obesity, neurodegenerative disorders and various other health challenges.



- Supports liver health & detox
- Anti-oxidant & anti-inflammatory properties
- Improves insulin sensitivity & cholesterol
What Is Silybin?
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Silybin is unique to a group of flavonolignans in milk thistle seeds, which are collectively called silymarin.
Silymarin consists of six constituents which are concentrated in standardized milk thistle extracts. They are silybin A, silybin B, isosilybin A, isosilybin B, silydianin and silychristin.
Silybin A and silybin B are diastereoisomers: molecular stereoisomers that are not mirror images of one another. Silybin specifically refers to the combination of silybin A and silybin B.
In sum, silymarin is the group of active flavonolignans in milk thistle extract and silybin is the main constituent of silymarin.
Effects of Silybin
To date, milk thistle extracts containing silybin have exhibited hepatoprotective, anticancer, antidiabetic, anti-inflammatory, antioxidant and renoprotective properties. Silymarin constituents have been observed to support liver health by:
- Stimulating protein synthesis in the liver and regenerating/replacing damaged/dead hepatic cells;
- Protecting the liver from damage caused by over-the-counter medications;
- Protecting the liver and kidneys from the toxic effects of Death Cap mushrooms (Amanita phalloides), as well as poisonous bites and stings;
- Preventing bile stagnation and gallstone formation by decongesting the liver and gallbladder;
- Protecting the liver and kidneys against damages from tetrachloride and other industrial poisons.
Milk Thistle Antioxidant Profile
Aside from its capacities to protect and support liver function, milk thistle extract is also a potent antioxidant. It scavenges for ROS (reactive oxygen species) such as free radicals, heavy metals and food additives, reducing damage from oxidative stress.
Glutathione is one of the body’s most needed antioxidants because it helps regulate the liver detoxification process. Put simply, the more glutathione that is available, the better the liver is able to cleanse and restore itself. In human tests, silymarin extract has increased glutathione levels by as much as 35 percent.
Superoxide is the body’s most prevalent oxidizing agent. It is estimated that every human sustains hundreds of millions of cellular “hits” from superoxide free radicals each day. The antioxidant needed to stop the damages from superoxide is called superoxide dismutase (SOD). Silybin extract has been observed to increase the synthesis and utilization of SOD.
Silybin and Cancer Treatment
Silybin has been observed to work against cancer cells without inducing the toxic side effects often associated with pharmaceutical therapies. In in-vivo and in-vitro trials, silybin has been shown to suppress cellular transformations caused by inflammation, regulate cellular apoptosis, inhibit angiogenesis in tumors, and impede metastasis of some cancerous cells.
Silybin is most noted for its capacity to act as an adjunct therapy in combination with mainstream cancer treatments. It effectively reduces the damage incurred from radiation and chemotherapy sessions.
Silybin Side Effects
Milk thistle has been consumed for thousands of years and is not commonly associated with severe side effects. Similarly, silybin seems generally well tolerated by humans.
Numerous clinical trials have been conducted on milk thistle extracts. In these studies silymarin supplementation was not observed to cause serious or lasting side effects, even at high dosage levels for extended periods (up to 41 months).
Silybin may interact with some prescription and over-the-counter medications. For instance, silymarin may interact with prescription medications used to enhance liver function, alter blood glucose levels and/or treat disorders of the immune system.
Be sure to speak with your doctor before beginning silybin supplementation to ensure safety and efficacy.
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Article last updated on: April 28th, 2018 by Nootriment