The liver functions to cleanse our body of pollutants and internally-generated waste products like ammonia.1 It is the largest organ inside your body and has at least 500 life-sustaining functions.1
Liver function declines with aging.2 Left unchecked, toxic overload can lead to conditions ranging from cirrhosis and hepatitis to non-alcoholic fatty liver disease and even cancer.3-6
Optimal liver function is critical to all aspects of health.1 Maintaining robust liver capacity ensures our body will effectively rid itself of heavy metals, pollutants, and other toxins.1
Milk thistle has been used to detoxify the liver and even help liver cells regenerate themselves for over 2,000 years.6,7 Studies confirm that milk thistle can protect liver function, prevent liver damage, and normalize elevated liver enzyme levels.8-10
Scientists have discovered a novel way of delivering more of the active constituents in milk thistle to your liver–about ten times more — which as you’ll soon read is great news.11,12 This new delivery system also resulted in 5-fold greater concentrations of silybin in the bloodstream which is important because milk thistle extracts have potent systemic benefits.13
Extracts from milk thistle (Silybum marianum) have been used for centuries for their preventive and curative properties for liver disease.7,9 Modern science has identified the specific components in milk thistle extracts responsible for these protective effects,9 one being silymarin.14,15
Silymarin is a potent antioxidant and anti-inflammatory, which helps it fight the root causes of liver disease.6,16-19 Further research has identified a specific molecule, called silybin, as the most active component in silymarin.9,20
Why Our Livers Love Milk Thistle
There are many different kinds of liver disease, each with its own set of causes, symptoms, and impact. But virtually all liver disorders come down to a few main causes, namely oxidative stress and inflammation that lead to liver cell damage and loss of function.3
While most of us take our liver for granted, this workhouse of the body labors tirelessly to rid the body of accumulated toxins. Fortunately, the liver is well-equipped to deal with those toxins, operating a diverse field of enzyme-driven detoxification systems to neutralize the majority of threats.2
But those systems operate at a high cost to the liver itself, generating massive amounts of free radicals that damage liver cell membranes and release inflammatory cytokines.21
Over time, all of those insults can damage your liver, impairing its ability to carry out its multiple detoxification tasks, and also its many other functions, such as producing bile to aid digestion, ridding the body of dangerous ammonia, making coagulation factors that help blood clot properly, manufacturing hormones, and a host of other physiological processes essential to life.
That is what makes prevention absolutely essential and what makes milk thistle so vital to maintaining a healthy liver.
Daily Protection For Your Liver
Milk thistle works in various unique ways to protect your liver on a daily basis from the onslaught of toxic materials and oxidative stress. Here are just a few of the ways that milk thistle provides protection for one of your most valuable organs.
- Silymarin’s potent antioxidant properties help to prevent and even reverse the oxidation of fats in liver cell membranes that lead to inflammation and leakage of liver cell contents into the bloodstream.9,22,23 Silymarin boosts liver cells’ levels of natural antioxidant molecules such as glutathione, helping cells recover more quickly from oxidative stress.5,24
- Silymarin reduces liver inflammation by inhibiting enzymes, such as 5-LOX, COX, and NFkB, that produce inflammatory cytokines and other deleterious signaling molecules that contribute to liver damage.25,26 Even if liver damage has already occurred (as it has in most of us by middle age), silymarin has powerful regenerative properties, boosting liver cells’ ability to make new proteins and repair damage before it can spread.25
- Silymarin has been shown to prevent liver fibrosis, the first step in the last stage of advanced liver disease, by protecting normal liver structural cells and blocking them from turning into fibrous, muscle-like cells.27,28
- Silymarin has the ability to block “Phase-I” liver enzymes that can activate toxins we ingest.25 “Phase-I” liver enzymes convert certain compounds into oxidative substances that are difficult for the body to excrete.2 In the presence of silymarin, these dangerous molecules can be excreted harmlessly in urine.
Alcoholic Liver Disease
Of all the substances that can damage your liver, one of the best-known is alcohol. While low-level consumption of alcohol (especially wine) has proven health benefits, larger amounts impose extreme oxidative stress on liver tissue.29 Ultimately, that leads to inflammatory changes and the release of cytokines that damage the liver and other tissues, which creates a vicious cycle and leads to still further oxidative stress.2,19,30 Animal studies have found that silymarin has the potential to reverse alcohol-induced liver damage.16,19
In animal studies, acute alcohol administration produced prominent accumulations of fat in liver cells, with small areas of dead tissue (necrosis), accompanied by a rise in liver enzymes in the blood (from leaking, dying cells).16 Alcohol also sharply lowers the liver’s content of glutathione (the main intracellular antioxidant), leaving cells vulnerable to further oxidant damage. In addition, excessive alcohol consumption markedly increases levels of the destructive cytokine TNF-alpha. Amazingly, when the animals were supplemented with silymarin, all of these adverse alcohol-induced changes were prevented.19
A human study of 36 people with chronic alcoholic liver disease revealed similar findings.31 Patients took either silymarin or placebo every day for six months. At baseline, all patients had elevations of liver enzymes and other markers of liver damage in their blood; they also had biopsy-proven tissue damage.
Following treatment, however, all of the markers of liver damage had normalized in the silymarin group, with minimal changes among placebo recipients. Repeated biopsies revealed improvement in the silymarin group, but no changes in the placebo patients. This study was a powerful demonstration of silymarin’s liver-protective activity, and its ability to improve liver function in alcoholic patients.31
Non-Alcoholic Fatty Liver Disease
Non-alcoholic fatty liver disease (NAFLD) has rapidly become the most common cause of chronic liver disease in industrialized nations.32 The disease is a direct consequence of our high-fat, high-carbohydrate diets and our sedentary lifestyles.
Mainstream medicine has little to offer for those suffering from non-alcoholic fatty liver disease. Fortunately, silymarin holds out substantial promise.19 In fact, one study found that silybin was more effective than prescription rosiglitazone in certain areas of treatment.5
Animal studies have shown that both silymarin and silybin reduce oxidation of liver cell membranes, reduce blood liver enzyme levels, and enhance production of protective adiponectin.5,33
Human studies have also been very encouraging. Because non-alcoholic fatty liver disease is part of the metabolic syndrome, attempts have been made to treat it with insulin sensitizing drugs like metformin and pioglitazone, but with only modest success. In a 2012 study, researchers compared both drugs with silymarin (140 mg/day).34 All three treatments produced improvements in fasting blood sugar, lipid profiles, insulin levels, and insulin resistance, along with decreases in blood levels of liver enzymes. But the greatest decrease in the liver enzymes was seen in the silymarin group, indicating greater protection against liver damage.34
As promising as silybin is on its own, the availability of silybin in combination with phosphatidylcholine has proven to be a major step forward in managing non-alcoholic fatty liver disease. One early study of patients with non-alcoholic fatty liver disease, with or without the complication of hepatitis C infection, showed significant reductions in plasma markers of liver fibrosis (the first step towards deadly non-alcoholic steatohepatitis know as NASH), and significant improvements in insulin resistance, using a combination of silybin, vitamin E, and phospholipids.35
A more recent, larger trial of a unique combination of silybin with phosphatidylcholine and vitamin E demonstrated significant improvements in liver enzymes, insulin resistance, and the appearance of liver tissue on biopsy, none of which were seen in placebo recipients.27 In addition, body mass index was completely normalized in 15% of supplemented patients, compared with just 2% of controls. And in patients with hepatitis C infection, the supplement improved markers of liver fibrosis.