Milk Thistle — also known as Mary thistle or holy thistle — has been used as an herbal remedy since ancient times to treat liver dysfunction and gallbladder problems.
In the 1st century AD, Roman naturalist Pliny the Elder wrote about the healing properties of Milk Thistle for supporting liver health.
Thousands of years later, modern-day people continue to utilize the benefits of taking Milk Thistle supplements.
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What is Milk Thistle?
Milk Thistle — known scientifically as Silybum marianum — is a plant in the Asteraceae family, native to the Mediterranean region. It has since been naturalized across Central Europe, in North and South America, and in Southern Australia.
Milk Thistle is a prickly plant with distinctive purple flowers and white veins that run along its leaves. According to folklore, the plant’s milky white veins were caused by a drop of the Virgin Mary’s milk falling onto its leaves.
Milk Thistle contains a group of plant compounds known collectively as silymarin, which is the active molecule known to have antioxidant, antiviral, and anti-inflammatory properties.
Today, the best Milk Thistle supplements contain highly concentrated Milk Thistle extract with 65 to 80% pure silymarin.
Our Milk Thistle supplement, for instance, contains 80% silymarin to ensure the highest potency.
What are the benefits of taking Milk Thistle supplements?
1. Milk Thistle can support liver health
Milk Thistle is best known for its beneficial effects on liver functionality.
Silymarin, the active compound in Milk Thistle, is a powerful antioxidant that reduces free radical production in the body.
In numerous animal studies, Milk Thistle has been found to help ease liver damage caused by acetaminophen (from painkillers like Tylenol), alcohol, radiation, Iron overload, and many other toxins.
People with liver disorders will often add Milk Thistle into their supplement routine to have increased liver health support.
Some preliminary clinical trials have shown that patients with liver diseases who took a daily Milk Thistle supplement experienced improvements in liver function. These preliminary results are promising for Milk Thistle’s ability to support liver health, especially during specific chronic conditions.
2. Milk Thistle can help detox the gallbladder
As the gallbladder is interconnected with the liver, Milk Thistle is also used to support gallbladder health.
Silymarin is thought to stimulate the gallbladder in the same ways it affects the liver, by reducing free radical production and supporting detoxification.
However, more research is needed, as studies focusing specifically on Milk Thistle’s effects on the gallbladder are lacking.
3. Milk Thistle may reduce acne and promote healthy skin
Considering Milk Thistle (namely its active ingredient silymarin) has antioxidant and anti-inflammatory effects, it may be able to play a role in clearing up acne.
One scientific study examined people with severe acne, and gave them 210 milligrams of silymarin a day. After 8 weeks of treatment, the patients saw a 53% reduction in acne lesions, while the placebo group didn’t experience any significant reduction at all.
These preliminary results are promising, though research is still very behind on the connection between silymarin and acne.
4. Milk Thistle may prevent cognitive decline
Milk Thistle has actually been used as a natural remedy for the treatment of neurological disorders for over 2,000 years.
Milk Thistle may be able to help prevent mental decline due to silymarin’s antioxidant and anti-inflammatory properties, though the scientific research is still lacking.
For example, several animal studies found Milk Thistle could increase resistance to oxidative stress. One animal study showed that daily supplementation of silymarin could contribute to the prevention of age-related degenerative processes in the brain.
Unfortunately, there haven’t been any human trials on how Milk Thistle could affect neurological conditions yet. As such, it’s unknown whether it has the same neuroprotective benefits on aging humans.
5. Milk Thistle may improve bone health
Some researchers claim that Milk Thistle may potentially prevent or delay bone loss due to osteoporosis.
One study found the use of silymarin supplementation demonstrated possible effects in preventing bone loss and strengthening bone structure in mice. They suggest that, if more research is conducted, it’s possible that Milk Thistle supplements could become an alternative treatment for postmenopausal women suffering from osteoporosis — though more research is needed, especially clinical trials in humans.
Again, however, Milk Thistle has only been scientifically shown to stimulate bone mineralization in animals. How it may affect the bone health of humans is still yet to be discovered.
6. Milk Thistle may help diabetics lower their blood sugar
It’s recently been discovered that Milk Thistle has hypoglycemic and hypolipidemic properties — in simpler terms, it may be helpful in reducing blood sugar and balancing cholesterol.
As a result, some researchers have suggested Milk Thistle could be a useful complementary therapy for those with type 2 diabetes, though more research is needed. This is because silymarin may help improve insulin sensitivity and may help decrease blood sugar levels in a similar way certain diabetic medications work.
One systematic review and meta-analysis showed people that supplement daily with silymarin saw a significant reduction in their fasting blood sugar levels.
More scientific studies are needed before it’s possible to make any concrete recommendations, however.
Milk Thistle interactions and side effects
Milk Thistle is generally considered safe when taken in appropriate doses. Some people may experience an upset stomach, bloating, or diarrhea at high dosages.
Milk Thistle may interact with diabetes medications, as it can also cause blood sugar levels to reduce in the same way diabetes medications work. You should consult with your doctor before taking Milk Thistle if you have diabetes, are pregnant or nursing, have a history of breast/ovarian cancer, or have other estrogen-sensitive conditions.
Milk Thistle supplements may reduce the effectiveness of the antibiotic metronidazole. You should also avoid taking Milk Thistle supplements if you are on the hepatitis C medication simeprevir, or if you take sirolimus, an immunosuppressant. For a full list of Milk Thistle interactions, go here.
People with ragweed allergy may also be allergic to Milk Thistle as well and should consult their doctor before beginning milk thistle supplementation.
The bottom line
Even though this healing herb has been used as a natural remedy for thousands of years, the scientific world still has a lot of catching up to do before we can fully understand Milk Thistle’s true potential.
If you’d like to give Milk Thistle a try, we offer a powerful concentrated extract containing 80% silymarin to ensure the highest quality.
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