Last modified on October 20th, 2023
You may have heard of it and be wondering, milk thistle is good for what exactly? Milk thistle is one of the most potent natural supplements, especially for liver health. Below, we will cover what the herb is good for and what you should know about this supplement.
What is Milk Thistle?
Milk thistle is also known as Silybum marianum, holy thistle, Marian thistle, and Mary thistle.
You’ll often also just hear it called silymarin.
The milk thistle plant is native to Europe. Early colonists introduced it to North America. Traditional and folk medicine is for liver and gallbladder problems and disorders.
As a dietary supplement, milk thistle in people can help with indigestion, diabetes, hepatitis, cirrhosis, alcoholic and non-alcoholic liver fibrosis, and cholestatic liver disease. In fact, as a potential alternative treatment for hepatitis, the herb has shown a great deal of promise.
A flowering plant, milk thistle, is from the daisy family, according to the National Cancer Institute.
Silymarin is the active ingredient in milk thistle. This comes from the milk thistle seeds. You can find it in supplement form as a tea, tablet, liquid extract, or oral capsule.
The herb and the silymarin compound in milk thistle has anti-inflammatory and antioxidant properties.
Milk Thistle Benefits
The following are some of the things milk thistle is good for:
Supports Liver Health
Undoubtedly, the biggest thing the herb is good for is liver health and detoxification. Liver benefits are the primary reason most people take it.
This herb can cleanse the liver and help rebuild liver cells. Taking it can reduce liver damage. Silymarin removes toxins from the body when they process through the liver.
For heavy drinkers, silymarin for alcoholic symptoms may help reverse the toxicity of that consumption. It can also help reduce the effects of heavy metals in our water, pesticides in food, and pollution in the air around us.
Our liver is our largest internal organ, responsible for a range of functions related to detoxification. Our blood condition is reliant on our liver health. The liver plays a vital role in hormone production, removing harmful substances from the body, detoxifying, and releasing sugar into the bloodstream to give us steady energy. The liver also secretes bile into the small intestine, allowing us to absorb fat from our foods.
When you deal with liver problems or dysfunction, it can lead to many health problems and reduce your quality of life.
Specific conditions related to the liver these herbal supplements can benefit include acute and chronic hepatitis, alcoholic liver disease, and toxin-induced liver disorders. Chronic liver disease and liver inflammation can be helped by milk thistle, as can virus liver diseases like viral hepatitis.
In 2016, a study in mice found milk thistle improved liver damage induced by diet. Researchers in clinical trials believe most of the liver-related benefits for people with hepatitis and other liver disorders are because silymarin is an antioxidant that reduces the production of free radicals.
It’s likely future research, such as randomized trial studies, will continue to look at the benefits for liver health and its role in the world of alternative therapies and CAM therapies.
What About Milk Thistle for Hepatitis C?
While this herbal remedy does appear to have very strong benefits for liver health, it’s not supported to treat hepatitis C. A number of studies have found it’s not effective for this, but it could support the overall health of your liver, which could reduce symptoms.
May Help with Non Alcoholic Fatty Liver Disease
Above we generally talk about the benefits of silymarin for liver health, but because of its increasingly prevalent, we also wanted to highlight potential benefits for non-alcoholic fatty liver disease or NAFLD.
NAFLD is a spectrum of conditions that can range in severity. It can include fatty infiltration up to fibrosis or cirrhosis. The fat on the liver can be viewed on an ultrasound, and it’s often associated with obesity, type 2 diabetes mellitus, and hyperlipidemia.
If you have both fat storage and inflammation-causing liver damage, it’s known as nonalcoholic steatohepatitis or NASH. NASH can lead to inflammation and scarring that’s so severe it can cause liver failure and the need for a liver transplant.
Researchers believe the plant-based supplement might have potential benefits. The plant extract benefits the liver by boosting the production of enzymes your liver uses to eliminate toxins.
There are several studies showing the herb may lower liver enzymes AST and ALT, which are markers of liver damage. The lower those levels in people, the healthier your liver probably is, and the more you can reduce your risk of death occurring prematurely.
There have also been studies showing milk thistle can reduce fibrosis caused by NASH in the liver.
Limits the Spread of Cancer
The extract, again probably because of the silymarin it contains, may help reduce the risk of developing different types of cancer, including breast cancer.
Silymarin may have anticancer benefits and benefits for cancer patients because it boosts the immune system and combats DNA damage. This herb can reverse cancerous tumor growth potentially.
In test-tube studies, silymarin has shown protective factors against breast, lung, and prostate cancers. In 2007, researchers from the University of Minnesota reviewed many studies. The researchers said they found strong evidence for the anti-cancer and liver-protecting effects.
Around 50 to 70% of silymarin in the plant is a type called silibinin or silybin. Silibinin is an antioxidant that protects healthy cells from damage and mutation. This antioxidant also prevents toxins from lingering in the body, helping cells renew themselves and counteracting free radical damage.
Some animal studies of milk thistle have found silymarin might also help conventional treatment like chemotherapy work more effectively, and it can reduce the side effects of cancer treatments. Most of the studies looking at these benefits and the effectiveness of milk thistle so far are in animals, however.
There is currently a clinical trial underway to look at the possible benefits of the herb to help with the medication-related side effects that occur following the treatment of acute lymphoblastic leukemia.
May Help Control or Prevent Diabetes and Supports Healthy Blood Sugar Levels
Studies are finding the effects of milk thistle may be good for people with diabetes. In 2015, research published in Phytomedicine found taking milk thistle for 45 days helped reduce general inflammation in adults with type 2 diabetes more effectively than a placebo.
Researchers think silymarin may reduce oxidative stress, which is often linked to complications of diabetes and insulin resistance.
There was a 2016 systematic review with metadata of clinical studies and research concluding silymarin seemed to reduce HbA1c levels and fasting blood glucose.
The National Institute of Health says there’s based on studies of milk thistle, there’s compelling evidence that silymarin can help with the control of blood sugar in people and maintaining blood sugar levels similar to diabetes medication.
May Help Lower High Cholesterol
When you have high cholesterol levels, it can lead to negative effects on your heart health. Taking it regularly may lower your cholesterol levels and also give heart health a boost in other ways.
The herbal extract, in preliminary research, has been shown to reduce inflammation, clean the blood, and prevent oxidative damage that occurs in the arteries.
Gallstone Prevention
Your liver is a digestive organ, and it processes everything, including nutrients and toxins passing through our bodies.
The liver works closely with other digestive organs, including the intestines, kidneys, and gallbladder. Because of this relationship, when you improve the function of your liver, you can enhance its function, also.
It may be able to increase bile flow and therefore prevent gallstones.
Gallstones form when cholesterol and other substances bind with bile. They can eventually become solid and get lodged in the lining of your gallbladder.
Has Anti-Aging Effects and Brain Health Benefits
For more than two thousand years, traditional remedies have relied on silymarin to treat conditions like Parkinson’s and Alzheimer’s.
The anti-inflammatory and antioxidant properties of silymarin could help prevent declines in brain function you experience as you age. In both test-tube and animal studies, silymarin is proven to avoid oxidative damage to brain cells. That oxidative damage could be part of mental decline.
Studies have also uncovered the fact that the plant can potentially reduce the number of amyloid plaques in animals who have Alzheimer’s. Amyloid plaques are clusters of amyloid proteins that build up in the nerve cells as you age.
Amyloid plaques tend to be very high in the brains of people who have Alzheimer’s.
Supports Bone Health in Postmenopausal Women
In animal and test-tube studies, the active components in the plant stimulate bone mineralization. That stimulation may help protect against bone loss. Researchers think silymarin could be helpful to prevent or delay bone loss in women who are postmenopausal.
Promotes Skin Health and Treats Acne
What many people who struggle with acne don’t realize is that it’s a chronic inflammatory skin condition. Oxidative stress, as a result, likely plays a role in acne. The plant may help if you have a skin condition because it’s anti-inflammatory and has antioxidant properties.
In one study, people with acne taking 210 milligrams of silymarin a day for eight weeks had a 53% reduction in acne.
Improves Allergic Asthma Symptoms
Since it has anti-inflammatory benefits, this herbal remedy might help with allergic asthma symptoms. It can help block the release of histamines that cause these symptoms. In 2011, a study found an extract with this herbal remedy in it reduced hay fever symptoms when combined with an antihistamine.
Additionally, it’s a very strong antioxidant, so it can support the liver’s natural detox abilities, and that can, in turn, help your body eliminate histamines.
Increases Breast Milk Production
There’s evidence taking milk thistle extract can help increase lactation and breast milk production. It’s classified as a galactagogue, which means that it increases lactation. Other examples of galactagogues include fenugreek and ginger. Like these herbal remedies, milk thistle is thought to signal the body to increase milk output, especially when you pair it with more frequent nursing or pumping or also use fenugreek.
What Are the Side Effects of Milk Thistle?
When taken orally and as instructed, the supplement is considered safe with minimal potential adverse effects based on scientific studies. Even in studies where high doses were administered for relatively long periods, only around 1% of participants had side effects.
If you were to experience common side effects, they’d likely be mild and can include upset stomach, nausea, diarrhea, or bloating, as well as other gastrointestinal issues.
If you’re pregnant or breastfeeding, you should avoid milk thistle or talk to your doctor simply because there are no safety data or hard scientific evidence during pregnancy or breast feeding.
If you’re allergic to the Asteraceae Compositae plant family, you might experience allergic reactions to the plant.
Milk thistle can have estrogen-like effects, so be cautious using it if you have a hormone-sensitive condition, as some breast cancer patients do. Other hormone-sensitive conditions and diseases in patients include ovarian cancer, uterine fibroids, or endometriosis.
If you take any medications, speak to your doctor before you take the milk thistle. Milk thistle may interact with allergy medicines, anti-anxiety medicines, and blood thinners, for example.
Milk Thistle for Dogs
Along with being helpful to people, many people give milk thistle supplements to their dogs. For dogs, a milk thistle product is good for:
- Cushing’s disease
- Pancreatitis
- Acute or chronic hepatitis
- Diabetes
We have an entire post that explores more about the benefits of milk thistle for dogs that we encourage you to check out.
How to Take Milk Thistle
Since it is such a popular supplement, you have many options as far as how you use the extract. You can take capsules and liquid extracts or brew it as tea, for example. The herb is categorized as a supplement and not a drug. No supplements have to undergo the regulatory standards that drugs do by the Food and Drug Administration, so there’s no standard dose or duration of milk thistle treatment standardized.
Overall, the amount of active ingredients and the dosage varies widely between products, so read the labels carefully to make sure you’re taking it correctly.
Dosage: How Much Milk Thistle Should I Take?
Most people take anywhere from 20 to 300 milligrams a day as their dose of milk thistle. If you’re taking it primarily for liver health, you might consider taking 150-milligram doses of milk thistle one to three times a day.
When choosing a supplement, look for one that comes from a high-quality brand and contains pure extract. The label should indicate there’s at least 80% pure milk thistle extract in the product, ideally.
If you want to have it in tea form, you can get more health benefits that way.
Be careful about taking a combination supplement or combination product. Sometimes these might have low levels of actual silymarin because there are so many ingredients. If you have an adverse reaction to a combination product, you won’t know which ingredient led to it.
What Are the Best Milk Thistle Supplements?
Our picks for the three best supplements that contain milk thistle are detailed below.
Nature’s Essentials Liposomal Milk Thistle
This is one of the best supplements because it contains full-spectrum silymarin and it’s a liposomal formula. Liposomal supplements are excellent for absorption, so you’re getting the full benefits. This product is lab-certified as well. You only have to take one capsule per day because of the potency and bioavailability.
Thorne Siliphos
This botanical complex is designed for liver health and antioxidant support. The supplement helps support glutathione levels, and the capsules use a phytosome preparation so that your body can absorb it optimally and it’s delivered effectively to the liver. The Thorne brand manufactures all its own products and has been in business for more than 30 years, and its facility in Charleston, SC, is third-party certified.
Quicksilver Scientific Glutathione Complex
This powerful liposomal complex supports healthy glutathione levels and natural detoxing. Each five mL of this liquid supplement contains glutathione, nanoparticles of milk thistle, and a B vitamin complex. Both glutathione and milk thistle have low bioavailability when they’re taken orally. This formula uses a phospholipid delivery system, so you’re getting the best benefits in the most efficient way possible
Key Takeaways
This natural medicine is a potentially potent supplement and natural health remedy. Among herbal products, milk thistle products are good for many things, including promoting liver health, protecting cognitive function, and reducing inflammation. They can also help remove toxic substances from the body, and these dietary supplements have powerful antioxidant effects. They can improve insulin sensitivity, and these plant compounds, according to medical journals and medical literature, also have anti inflammatory properties.
Along with the benefits we detailed above, the active substances in the plant may help with weight loss and reduce allergic asthma symptoms. If you have high levels of alcohol consumption, the antioxidant and anti-inflammatory effects may help you stay healthier and begin healing your liver. Specific liver conditions that the herbal remedy may help with include alcoholic hepatitis and alcohol-related liver disease.
Research studies show the potential for an extract of milk thistle to improve liver function and liver function tests in nonalcoholic fatty liver. Future studies will hopefully uncover exciting developments as well.
If you’re interested in taking milk thistle, consult with a health care provider, mainly if you take any medicines or have an underlying health condition. Don’t start taking anything new without first having a conversation with your healthcare provider.
Ashley Sutphin Watkins
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