What Does Milk Thistle Do in the Body?

Herbalists have know about the long list of milk thistle benefits for over 1,000 years. Milk Thistle decreases inflammation, modifies the activity of important liver enzymes, and increases bile production.

As a result, it helps the body deal with liver disease, heart disease, diabetes, and skin conditions, and reverse the toxic effects of air pollution, industrial chemicals, antibiotics, and prescription medications. All of these milk thistle benefits are found in the seeds of this common weed.

What Does Milk Thistle Look Like?

Milk thistle is an ordinary plant that offers extraordinary benefits. If you live in any of the world’s temperate zones between the tropics and the poles, chances are that you have seen milk thistle.

It flourishes in fields and flower beds where it is not “supposed” to grow. Milk thistle has lance-like leaves with prickly edges. Purple flowers bloom from the top of the plant, which may grow from 1 to 6 feet (25 to 300 cm) tall.


milk thistle field omnibiotics liver health


The leaves have milk-white veins and yield a milky white sap that gives the plant its name. The plant can be eaten as a vegetable, but a group of seven healing chemicals known as silymarin is usually extracted from its seeds. The terms “silymarin” and “milk thistle” are used interchangeably.

Sometimes a specific component of silymarin has more healing efficacy than others, but silymarin always contains all seven healing milk thistle chemicals. It is one of the main contributing factors to most of the known milk thistle benefits.

What Are the Benefits of Milk Thistle?

The list of milk thistle benefits is quite long. It ranges from the mundane, such as fighting hangovers, to the life-saving, such as protecting the liver from fatal tissue changes after poisoning with the Amanita death cap mushroom. Milk thistle supports the structure and function of your body to:

  • Transform potentially deadly toxins into harmless substances.
  • Fight viral infections.
  • Stop liver damage caused by alcoholic liver disease.
  • Reverse the effects of fatty liver disease.
  • Protect against breast, cervical, liver, prostate, and skin cancers.
  • Lower blood sugar levels in type 2 diabetes.
  • Heal sun-damaged skin.
  • Stop seasonal allergies.
  • Help lower cholesterol.
  • Help prevent gallstones.

Let’s take a look at these ten healing benefits of milk thistle and the milk thistle extract called silymarin one by one.

1. Milk Thistle Extract Can Save Your Life

There’s no more commonly toxic mushroom than Amanita phalloides, the “death cap” mushroom. Looking a lot like some of the button mushrooms you might buy at the supermarket, this mushroom contains the deadly amatoxin, which can cause fatal liver failure over a period of two to five days.

Death cap mushrooms are found in the wild in Europe and in the United States. Poisoning by death cap mushrooms is surprisingly common in the United States. In a single 14-day period in 2016, 13 people were poisoned by wild-crafted death cap Amanita mushrooms just in the San Francisco Bay Area.[1]

There are only two treatments for amatoxin. One is a liver transplant. The other is treatment with silybin, the most abundant chemical in milk thistle seed. Doctors usually would give mushroom poisoning patients silybin by IV, but sometimes it is taken as capsules.

milk thistle seeds leaf for liver support omnibiotics supplement


Milk thistle can help you avoid a liver transplant

In a two-year period in Germany, 17 out of 18 death cap poisoning patients treated with this milk thistle extract made full recoveries, as long as treatment was started within 48 hours of eating the mushrooms.[2]

Milk thistle as a treatment for amatoxin poisoning can save your life, and it can also spare you from having a liver transplant. How would you convince a skeptical doctor to give you the herb that could save your life? Most doctors want to know how silymarin works in these cases.

The evidence is that it stimulates the production of an enzyme called nucleolar polymerase A. This enzyme protects the outer membranes from a process called lipid peroxidation. It also stimulates the production of RNA that allows the liver to build the proteins it needs to repair damage by the toxin.

If your doctor understands how silymarin works, you are more likely to get this life-saving treatment. This is one of the milk thistle benefits that can potentially, and literally, save your life.

2. Milk Thistle Fights Viral Infections

Many people who have chronic viral hepatitis take milk thistle, with good reason.

Twelve clinical trials confirm that the milk thistle extract silymarin is as effective as standard medications for lowering liver enzymes (ALT and AST) and preventing fibrosis of the liver in hepatitis B. (However, that doesn’t mean that prescription medications don’t work, the combination of prescription medication plus silymarin works better than either used alone.)[3]

Milk thistle also works as a lead-in therapy for “hard-to-treat” hepatitis C infections. It doesn’t cure hepatitis C all by itself, but it helps medications work better if the silymarin is used first.[4] And it can make a huge difference in quality of life. Your skin won’t be as itchy. You won’t have as much vomiting and diarrhea, and your skin may return to its normal tone.

A clinical trial involving over 1,100 people who had hepatitis C found that people who took silymarin for several years had better liver enzyme levels (lower AST), better quality of life, and fewer symptoms. Participants in the study who took milk thistle had measurably less fatigue, nausea, liver pain, anorexia, and muscle and joint pain. They reported significantly better general health. They were also less likely to develop cirrhosis of the liver.[5]


healthy liver animation fighing virus


How Does Milk Thistle Stop Cirrhosis of the Liver in Viral Hepatitis?

Research shows that milk thistle benefits the liver in many ways. The way viral infections damage the liver is by setting off an inflammatory cascade. Inflammation “takes out” weak liver cells. As a result, the immune system generates still more inflammation to remove nearby healthy liver cells that are no longer connected.

The liver then fills in the gaps with fibrous tissue.[6] Milk thistle works by stopping the immune system from generating too much inflammation in the liver, which allows it to respond to other treatments.[7] Milk thistle doesn’t just help the liver recover from hepatitis B and C.

It also stops the hepatitis C virus from entering liver cells to cause the infection.[8] In addition, it can make HIV infected cells go into a kind of hibernation that keeps the AIDS virus from spreading.[9] And it keeps flu viruses from replicating themselves.[10]

Furthermore, clinical researchers suggest that one way to keep from coming down with the flu is to take milk thistle on a regular basis. Milk thistle by itself won’t absolutely stop the infection, however, it will limit the infection so that discomfort is minimal and recovery is swift.

3. Milk Thistle Stops Liver Damage Caused by Alcoholic Liver Disease

Silymarin from milk thistle helps heal liver damage in alcoholics in at least three important ways. This milk thistle extract:

  • Neutralizes free radicals generated by the breakdown of alcohol in the liver. Additionally, the antioxidant silymarin counteracts free radicals released when the liver processes over the counter pain relievers and common household chemicals.
  • Stimulates protein synthesis. As a result, increased activity of RNA allows the liver to make the proteins it needs to repair itself.
  • Enhances the antioxidant action of glutathione made by the liver. Silymarin boosts the natural free radical defenses of the liver.[11]

In the 1980’s, before the hepatitis C virus was discovered, researchers conducted a large clinical trial of silymarin as a treatment for people who had chronic liver disease and who drank. Some of the people in the study could have had both alcoholic liver disease and hepatitis C.

Nonetheless, the study found that taking milk thistle reduced the risk of cirrhosis even when people who had alcoholic liver disease continued to drink.[12] Another clinical study found that people who have alcohol-related liver damage but take silymarin produce more of the antioxidant glutathione.[13] So if you struggle with alcoholic liver disease, then this is one of the most important milk thistle benefits for you.


4. Milk Thistle Stops Liver Damage Caused by Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease is a complication of having too much body fat. However, you don’t have to be obese to develop fatty liver disease.

Even though just 30% of Americans are obese, up to 46% have fatty liver disease.[14] Non-alcoholic fatty liver disease consists of a progression of liver problems that begin with non-alcoholic steatohepatitis and progress to fibrosis, cirrhosis, and liver cancer.

The initial symptoms of non-alcoholic fatty liver disease are usually vague.

You may feel tired all the time and not know why. Your skin color may be “off,” but not yellow the way it is in other liver diseases. You may find the willpower to diet but you don’t lose weight. Usually these symptoms occur a long time before your liver problems progress to fibrosis, cirrhosis, or even cancer. Sometimes something triggers liver cancer even before there are fibrosis and cirrhosis that your doctor can detect.[15]


healthy liver and fatty liver animation


How to Treat Fatty Liver Disease

The treatment for fatty liver disease is to lose your excess body fat by dieting. Dieting produces real rewards in reversing the condition.

  • Clinical trials confirm that losing 9 percent of your body weight leads to reductions in both inflammation and fatty deposits in liver tissue.[16]
  • Other clinical trials find that losing 8 percent of your body weight leads to lowering the amount of fat deposited in your liver.[17]
  • If you are able to lose 7 percent of your body weight by low-calorie diet, clinical research confirms that you will have less “ballooning” of liver tissue. Your liver will maintain its normal form and function for optimal blood circulation.[18]
  • And if you can lose at least 5 percent of your body weight by dieting, there will be significantly fewer fat deposits in your liver.[19]

The unfortunate reality is that most of have trouble losing even 5 percent of our body weight by dieting.

Fortunately, It’s Possible to Heal Your Liver With Milk Thistle.

One of the main reasons why there are so many milk thistle benefits is because milk thistle contains silymarin.

If you reduce your calories by any amount at all and also take silymarin, one clinical study tells us that you will see improvements in your liver enzymes faster. Dieting non-alcoholic steatohepatitis patients who took just a low dose of silymarin (210 mg a day) had improved ALT and AST in eight weeks.[20]

And silymarin even helps if you aren’t able to reduce your intake at all. A team of physicians in Naples (Italy) studied the effects of silymarin in 72 fatty liver disease patients who were able to eat the right foods, eliminating unhealthy fats and products like corn syrup, but who weren’t able to eat the right amounts, losing weight on a calorie-restricted diet. Here are the results:

After Three Months of Taking 540 mg of Silymarin Every Day:

  • ALT levels (a measure of liver cell death) fell from an average of 109 to an average of 75.
  • AST levels (another measure of liver cell death) fell from an average of 72 to an average of 48.
  • Ultrasound scans of the liver showed an average of 42 percent fewer fat deposits

Taking 540 mg of silymarin every day for three months did not completely reverse fatty liver, but it greatly improved it—even in patients who were not able to reduce their calorie consumption.[21] Silymarin will not be as helpful in patients who have advanced liver disease, and it has to be taken in a higher dose (700 mg per day) to help people in the advanced stages of fatty liver disease.

Even in these cases, however, clinical trials find that silymarin seems to cause a significant reduction in fibrosis, stopping the potentially deadly progression from fatty liver to fibrosis and more serious conditions.[22]

5. Milk Thistle Protects Against Cancer

Let’s be clear. Milk thistle or silymarin don’t cure cancer all by themselves. But they seem to help prevent certain kinds of cancer, and they increase the chances of successful treatment of cancer by medical and natural means. Here’s a look at how milk thistle benefits can help specific kinds of cancer.

Liver Cancer

The best evidence for silymarin/milk thistle in preventing and treating cancer is for hepatocarcinoma, or liver cancer. The silibinin component of silymarin (one of the seven plant chemicals that make up silymarin) kills cancer cells that are activated by hepatitis B.

It’s particularly useful in killing liver cancer cells that don’t have a “watchdog” gene called p53 that would ordinarily stop them from reproducing themselves.[23] Silibinin also stops the proliferation of liver cancer cells that is stimulated by alcohol (when people who have liver cancer continue to drink despite their disease).[24] If you take milk thistle extract, or silymarin, you get silibinin.

Breast Cancer

Milk thistle extract contains compounds that activate genes p21 and p53 so that they “turn off” breast cancer cells.[25] A clinical trial found that the healing chemicals in milk thistle extract that activate these genes are selectively absorbed by tumor cells.[26] Silymarin goes to the tissues where it is needed. Therefore, taking milk thistle benefits people who are struggling with or prone to breast cancer.

Colon Cancer

A clinical trial confirms that the colon absorbs the active chemicals in milk thistle. Colon cancer does not require IV silymarin. Cancer doctors who use natural drugs usually have a compounding pharmacy prepare them for intravenous infusion, at an expense of hundreds of dollars, but this is not necessary with silymarin for colon cancer.[27]

Taking both curcumin (the antioxidant from turmeric) and milk thistle extract increases the beneficial response to milk thistle.[28] The way milk thistle extracts work is by triggering a process called apoptosis, or “cellular suicide” in colon cancer cells. There are multiple chemicals in silymarin that stimulate apoptosis in colon cancer.[29] So, if you are dealing with colon cancer, then these milk thistle benefits might help you.

Prostate Cancer

There is some evidence that milk thistle extract as a whole (all seven chemicals, not just one of the seven chemicals in silymarin) slows angiogenesis, part of the process through which prostate cancer spreads to the rest of the body.[30]

Research studies tell us that it is a good idea to start taking milk thistle extract as soon as you know you have cancer, even before your treatment is scheduled. The healing chemicals in milk thistle extract don’t do all the work of beating cancer, but they can work with your body to ensure that you get the best possible results of a holistic treatment program.

6. Milk Thistle Lowers Blood Sugar Levels in Type 2 Diabetes

Milk thistle contains a compound called isosilybin that helps lower blood sugar levels in diabetes. It activates a cellular receptor called peroxisome proliferator activated receptor-gamma (PPAR-gamma). [31] This stimulates fat cells to take sugar out of the bloodstream and store it as fat. The result is lower blood sugar levels, but it is also weight gain unless you take other measures to control your diet.

If you can avoid weight gain, any PPAR-gamma activator is of great help in lowering your blood sugar levels and controlling your diabetes. It just requires some dietary restraint to work for your health overall. You will get better results using milk thistle for diabetes if you eat both less carbohydrates and fewer calories.

What Makes Milk Thistle Better Than Some Prescription Drugs that are Also PPAR-Gamma Activators?

It’s what milk thistle doesn’t do. Milk thistle stimulates the uptake of sugar out of your bloodstream. But the pharmaceutical PPAR-gamma activators also stimulate the production of new fat cells from your stem cells that otherwise would be making red blood cells. You do have to watch your diet when you use milk thistle for diabetes.

But you don’t have to worry about creating entirely new fat cells to soak up sugar and store fat even faster the way you do with some medications. How much difference will milk thistle make in your diabetes numbers?

One clinical study found an average blood sugar decrease of 10 mg/dl in people who used milk thistle for an entire year.[32] That’s not enough to call milk thistle a diabetes “cure,” but it’s about as much as you can expect from most diabetes medications. Therefore, the need for fewer medications is another check on the list of milk thistle benefits.

7. Milk Thistle Helps Heal Sun-Damaged Skin

The milk thistle extract silymarin heals sun-damaged skin from the inside out. Sometimes the UV-A rays in sunlight just cause inflammation. The skin heals inflammation with pigmentation. Tiny areas of inflammation produce spots that are darker than surrounding skin. Sometimes UV rays trigger the cellular suicide process called apoptosis in the skin.
Milk thistle benefits the skin because it’s chemicals known as silymarin block this process in the keratinocytes, the skin cells that create topmost, visible layer of your skin.[33]

Protecting keratinocytes helps to maintain your skin’s natural tones and normal contours, free of spots and sagging. Additionally, silymarin prevents the formation of skin tumors that become basal cell carcinomas and other forms of skin cancer.

It counteracts the formation of tumors, and it slows the production of tumors that have already formed.[34] Taking silymarin is not a substitute for using sunscreen, but it works with sunscreen to give your skin the greatest possible opportunity to rejuvenate itself.


woman with healthy skin beacuse of miilk thistle looking out window


8. Milk Thistle Stops Seasonal Allergies

If you haven’t found the right combination of lifestyle changes, nutritional supplements, and medication to control your hay fever or seasonal skin allergies, try milk thistle. Laboratory tests have shown that silymarin keeps your immune system from producing new T-cells that would trigger allergic inflammation.

At the same time, it helps keep existing T-cells alive so that they can fight infection.[35] It keeps T-cells from becoming exhausted by allergic response,[36] and it also stops specialized mast cells from releasing histamine. (Histamine is the chemical for which you take an antihistamine allergy medication.)

And while milk thistle won’t replace your emergency allergy medications, it reduces allergic responses so that severe allergic reactions are less likely. [37]

If you want to enjoy all of the milk thistle benefits for seasonal allergies, then you want to take it take every day, not just at the beginning of allergy season. It’s not something you take after your symptoms develop because it changes the reactivity of your immune system slowly, over a period of several days to several weeks.

When milk thistle works well, you don’t notice its effects. You just don’t have the allergic reactions you usually do.

9. Milk Thistle Lowers Cholesterol

Milk thistle helps your liver flush excess cholesterol away.

Most of your body’s cholesterol does not come from food. Instead, cholesterol is made by your liver. The liver releases some of its LDL cholesterol into the greenish-yellow fluid known as bile, which flows into the gallbladder and on to the small intestine. Bound to bile salts, this cholesterol mixes with stool and is removed with bowel movement.

Taking milk thistle extract on a daily basis will not have a big effect on your total cholesterol. Instead, silymarin stimulates your liver to remove the “bad” LDL cholesterol but lets it keep the “good” HDL cholesterol.

But there are other milk thistle benefits that help with lowering cholesterol. Silymarin also helps your blood vessels to generate a chemical called nitric oxide, which is also known as NO. The nitric oxide helps veins and arteries to relax. This lowers blood pressure and reduces the risk of blood clots. [38]

10. Milk Thistle Helps to Prevent Gallstones

Gallstones can be intensely painful. That’s despite the fact that they are usually composed of one or both of two soft substances, cholesterol or the liver pigment bilirubin. Gallstones don’t start as stones. They begin as gallbladder “sludge.” The liver doesn’t produce enough bile to push excess cholesterol down to the small intestine, so it accumulates in the gallbladder.

The fatty cholesterol sticks to proteins that are also found in the gallbladder, something like a greasy clog in a drain. Gallbladder sludge morphs into gallbladder gravel. These are harder bits of cholesterol- or bilirubin-laden debris. They can still be passed through the bile duct down to the small intestine, but they take longer and are only moved if the liver generates significantly more bile.

Gallbladder gravel can eventually solidify into gallstones. These hard accretions of wasted cholesterol and unneeded bilirubin are “stuck” in the gallbladder.

They can press against the sides of the gallbladder, especially when the liver restarts normal bile production. Usually the intense pain of a gallbladder attack occurs after a period during which the liver produced minimal bile, as during a low-calorie diet, followed by a period during which the liver produced extra bile to remove cholesterol absorbed from food, such as coming off a low-calorie diet.

The secret to avoiding gallstones is avoiding gallbladder gravel.nThe secret to avoiding gallbladder gravel is avoiding gallbladder sludge. And the way never to get your gallbladder filled with sludge is to encourage the healthy production of bile all the time. This is another one on the list of milk thistle benefits.

Silymarin Helps Your Body Produce Bile

Taking silymarin every day keeps your liver healthy so you don’t accumulate waste materials that can solidify in your gallbladder.

How do we know that silymarin really works for preventing gallstones? Clinical studies have found that taking 420 mg of silymarin a day for 30 days lowers the bile saturation index. This measurement is an indicator of how “sludge-like” bile is in the gallbladder or in the common bile duct in people who have had their gallbladders removed.[39]

Healthy changes in this index tell us that milk thistle extract doesn’t just help prevent gallstones. It also helps people who have had cholecystectomies (gallbladder removal) function as normally as possible. And what about that “mundane” application of milk thistle supplements, treating hangover?

The best way to use milk thistle to treat hangover is to take it every day whether you drink or not. That way silymarin stimulates the production of the enzymes the liver uses to detoxify alcohol even before you drink. This is one of the most popular and well-known milk thistle benefits.

What Is the Best Way to Take Milk Thistle?

Throughout this article we have used the terms “milk thistle” and “silymarin” interchangeably. That’s because the universally useful form of milk thistle is the silymarin extract. If you take silymarin, you are also getting all of its components, including silybin, isosilybin, silydianin, silychristin, and several others.

For almost every application of milk thistle, silymarin extract is best. It’s even used in treating Amanita mushroom poisoning. If you have a health problem that is immediately life-threatening, however, always seek medical care and follow your doctor’s advice.

What’s the Best Form of Milk Thistle?

While you can find powders and teas if you look hard enough, your best bet is a vegan capsule.

The capsule carries the silymarin to your small intestine where it is acted on in a more alkaline environment that keeps the healing chemicals intact. The best formulations of silymarin combine the chemicals that make up silymarin with at least a small amount (usually about 1000 mg) of the whole herb for maximum absorption.


man holding omnibiotics organic milk thistle supplement in nature


And How Much Silymarin is Enough?

Except in treating mushroom poisoning (which is really something that should be done in a hospital), 375 mg a day gets optimal results.

Milk thistle is not a natural product that works fast. You usually need to take milk thistle for about 30 days before you see the improvements in your health that you seek.

But trust us, it’s more than worth it. This list of milk thistle benefits doesn’t stop here. These are just some of the benefits we thought would be most useful for the reader. Here is another article for those who want to learn more about the benefits and uses of milk thistle.