Milk Thistle and Liver Health

A 2023 report found that liver disease was responsible for one out of every 25 deaths worldwide.¹

The situation has worsened in the U.S. Between 1999 to 2016, annual death rates from cirrhosis increased by a staggering 65%.²

Liver damage can result from obesity, fatty liver disease, excessive alcohol use, and certain toxins.

Injured liver cells lead to organ dysfunction and, when the damage is severe, lethal complications such as cirrhosis and liver failure.³

There is a lot that can be done to preserve liver health.

Managing a healthy weight; adhering to a high-fiber, plant-centric diet such as the Mediterranean dietary pattern; having a physically active lifestyle; and controlling oxidative stress are some liver protective methods.⁴

Researchers have found that milk thistle seeds and their components help defend the liver against harm, reducing injury and improving liver function.^5-7

In clinical trials, taking milk thistle extract has supported liver health and led to improvements in liver disorders, such as non-alcoholic fatty liver disease and cirrhosis.^5,8-10

The Liver: Our Biochemical Metabolic Workhorse

The liver is involved in every metabolic process in the body, including metabolism and regulation of blood sugar, proteins, and fats and lipids including cholesterol. It is also involved in the production of bile to aid in fat digestion, immunity, clearance of the body’s waste products, and much more.^11,12

Many factors have the potential to damage the liver, including excess alcohol consumption and non- alcoholic fatty liver disease (NAFLD).^13,14

Over time, and if not discovered and addressed, these often eventually cause scarring and fibrosis of liver tissue, known as cirrhosis. Ultimately all this can lead to liver cancer or the need for a liver transplant.¹⁵

Milk Thistle Defends the Liver

The good news: An herb called milk thistle can help protect against non-alcoholic fatty liver disease (NAFLD) and other types of liver injury.

It is one of the most widely studied liver health plants. Its seeds have been safely used in ancient medicines for centuries to treat liver disorders and other conditions.¹⁶

Milk thistle seeds are the source of a group of flavonoids referred to as silymarin.¹⁷

Silymarin has demonstrated potent activity against oxidative stress and inflammation, which are drivers of many types of liver disease and damage.^5,16,18

But milk thistle has the potential to protect the liver in many other ways as well. Evidence from preclinical studies has shown that milk thistle specifically protects the liver by:

• Strengthening liver cell membranes. Silymarins bind to liver cell membranes, helping to block the entrance of viruses and prevent damage from various toxins.^19-21
• Rejuvenating liver cells. Silymarin stimulates new protein production in liver cells, promoting cellular regeneration and rejuvenation.19
• Preventing fibrosis. Chronic liver damage causes fibrosis, scarring that eventually leads to cirrhosis. Milk thistle can modulate the activity of enzymes associated with this process. It can block activation of cells that contribute to fibrosis and help to maintain normal liver structure and function.^22,23

Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) has become one of the most prevalent liver diseases in the U.S.²⁶ We predicted this over 20 years ago as a result of increasing rates of obesity.²⁷

This condition is characterized by excess fat accumulation in the liver due to factors like being overweight or obese (particularly those with visceral obesity, usually associated with a large waist circumference), insulin resistance or metabolic syndrome, and type II diabetes. However, it is important to note that NAFLD can also occur in normal weight individuals.^14,26

NAFLD in its initial stages has no symptoms–diagnosis is usually made based on elevated liver enzymes on blood tests. In some cases, NAFLD progresses to a condition called NASH, non-alcoholic steatohepatitis, in which damage to liver cells and inflammation can eventually lead to fibrosis, cirrhosis, or hepatocellular carcinoma.^28,29

Preclinical research has shown that milk thistle extracts can alter the disrupted metabolism linked to non-alcoholic fatty liver disease, helping to reduce fat accumulation and safeguard cells from oxidative damage and death.^30-32

Extracts of milk thistle, especially its active compound silymarin, have been found to regulate lipid metabolism by affecting the expression of genes responsible for lipid synthesis and degradation.³³ Clinical trials have found that milk thistle alone or in combination with vitamin E and phosphatidylcholine reduces liver fat, fibrosis and liver enzymes in patients with NAFLD.^10,34,35

A meta-analysis of eight trials found that milk thistle extract significantly reduced liver enzymes in patients with non-alcoholic fatty liver disease, compared to controls.¹⁰

In randomized controlled trials, patients with non-alcoholic fatty liver disease who were treated with milk thistle extract alone or in combination with vitamin E showed significantly less fibrosis than those who received a placebo.^8,34-36

Advanced Liver Disease

Cirrhosis is one of the final stages of chronic liver disease, whether from NAFLD or other causes.37 While typically irreversible, clinical trials suggest milk thistle extract may offer potential benefits.

In one study, administering 420 mg of milk thistle extract daily to patients with cirrhosis was linked to an improved four-year survival rate. Researchers found that 58% of patients taking milk thistle survived, compared to 39% in the placebo group.³⁸

Other trials in patients with cirrhosis have found that milk thistle improved liver enzyme levels and quality of life.^9,39,40

While there are no cures for advanced cirrhosis or liver failure besides–in some cases–liver transplant,³⁷ ongoing research may reveal a promising role for milk thistle extract.

One clinical trial of 60 adults with alcoholic liver cirrhosis found that taking 450 mg daily of milk thistle extract improved liver health and reduced markers of liver fibrosis.³⁹

Preclinical studies have found that silymarin supplementation may reduce the harmful effects of toxins on liver function and pathology by regulating oxidative stress pathways.^41,42

Some medications may cause liver damage as a side effect. In clinical trials, the use of milk thistle extract with certain drugs, including ones used to treat multiple sclerosis and tuberculosis, significantly improved clinical status and liver enzyme levels.^43,44

Summary

Clinical trials show that taking milk thistle extract can support liver health and lead to improvements in the common condition non-alcoholic fatty liver disease, as well as in cirrhosis and other liver conditions.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.

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