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.1 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.3 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.4,5,6 Silymarin boosts liver cells’ levels of natural antioxidant molecules such as glutathione, helping cells recover more quickly from oxidative stress.7,8
  • 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.9 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.10
  • 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.11,12
  • Silymarin has the ability to block “Phase-I” liver enzymes that can activate toxins we ingest.9 “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.13 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.2,14,15 Animal studies have found that silymarin has the potential to reverse alcohol-induced liver damage.14,16

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.14 A human study of 36 people with chronic alcoholic liver disease revealed similar findings.17 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.17


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