Best Milk Thistle (Silymarin) Supplements Explained

Milk Thistle (Silybum marianum, Asteraceae) is a thorny herb that is widely distributed throughout southern Europe.

Milk thistle extract (also known as Silymarin as its most important flavonoid) can be very helpful in cases of overactive sport, systematic alcohol consumption, hepatotoxic drug intake, chronic diseases or other aggressive influences which can cause damage to the liver function.

The most valuable ingredient is the flavonoid known as silymarin (or silibinin). This flavonoid contains a special anti-hepatotoxic and hepatoprotective agent.

Top 5 Best Selling Milk Thistle Supplements



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California Gold Nutrition, Silymarin Complex Milk Thistle Extract Plus, 300 mg, 120 Veggie Caps, Milk-Free, Fish Free, Gluten-Free, Peanut Free, Soy-Free, Sugar-Free, Wheat-Free, Yeast-Free, CGN


California Gold Nutrition Silymarin
NOW® Silymarin, 300 mg, 200 Veg Caps


Now Foods Double Strength Silymarin
Natrol Milk Thistle Advantage V-Caps, 525mg, 60 Count


Natrol Milk Thistle
Jarrow Formulas Milk Thistle (Silymarin Marianum), Promotes Liver Health, 150 mg per Capsule, 200 Count


Jarrow Formulas Milk Thistle
Life Extension European Milk Thistle-Advanced Phospholipid Delivery, 120 Softgels


Life Extension European Milk Thistle

What Is Milk Thistle

Thistle (Silybum marianum, Asteraceae) is a thorny herb that is widely distributed throughout southern Europe. It also grows in the temperate climate zones in continental Asia.

It is artificially introduced on the territory of Central and North America and also in Australia and New Zealand, where it grows very aggressively with a reputation of weed. 

The herb is also known by the names Milk Thistle, Mediterranean Thistle, etc.

What Is the Milk Thistle Extract

The milk thistle extract is a dry mixture of the plant’s seeds, which contain a standardized rate of active flavonoids.

What Do We Need to Know About the Active Ingredients of Milk Thistle

The most valuable ingredient is the flavonoid known as silymarin (or silibinin). This flavonoid contains a special anti-hepatotoxic and hepatoprotective agent.

Scientists consider silymarin as a substance that can work as a potential antioxidant in hepatocytes (liver cells) and thus can protect them from damage.

What Are Positive Health Effects From the Use of Milk Thistle

Even the exact biological action mechanism is still not clear, facts confirm the direct effect of silymarin on the liver condition.

Proven Benefits:

  • Chronic hepatitis and liver inflammation prevention and treatment: Several different studies have shown that oral intake of silymarin has a positive impact on tests of liver enzymes in various types of hepatitis (chronic, viral or caused by alcohol).
  • Liver cirrhosis and alcoholic intoxication prevention and treatment: European cirrhosis treatment studies with oral intake of milk thistle show promising results in many of the studied patients, some of which have been taking supplements for five years. Damage from alcoholic intoxication, with main symptom hangover; gets greatly minimized in patients with silymarin treatment conducted within a few weeks.
  • Liver detoxification and regeneration: There is evidence that active flavonoids in silymarin help liver cells in their fight against various toxins. There is also data collected for the functional improvement after intake of silymarin in patients who have had treatments with various liver-damaging drugs.

Assumptions and Poorly Researched Arguments:

  • Anticarcinogenic effect: Experiments in this field are few and at an early stage, but enough to make an assumption of a link between intake of silymarin and delaying tumor growth in prostate, breast cancer and other kinds of cancer.
  • Anti-cholesterol effect: There is no data for results on humans according to studies. But there have been some tests, conducted on laboratory animals that prove that silymarin can lower their blood cholesterol levels.

Are There Side Effects and Contraindications When Taking Milk Thistle

People with allergies to plants of the Asteraceae (Compositae) family or daisies, common thistle, artichoke or kiwi may show an allergy to the silymarin complex flavonoids, so it is best to take the first dose in anticipation of an allergic reaction.

This, of course, might not occur, but it is important for a person to be prepared. 

There are records of people with allergies to milk thistle, who develop anaphylactic shock (Quincke's edema) after consumption of tea, tablets or extract.

Side Effects:

There have been studies on the milk thistle extract effects in people taking it for more than six years. Possible side effects: gastrointestinal irritation, itching, rash, headache, sneezing.

Very rare reports of people experiencing these side effects: gases, a burning feeling in the heart area, stomach pain, nausea, diarrhea, vomiting, weakness or fainting.

It is believed that most of these symptoms are an atypical autoimmune reaction, so if after taking silymarin you feel some of the rarest symptoms - it is best to stop and visit an allergist for skin testing.

Theoretically speaking, it is believed that the herb milk thistle may lower the blood sugar levels, so diabetics and patients suffering from low blood sugar are recommended to take it carefully.

Another medico-pharmacological theory recommends that women with unstable hormones should not take silymarin for its supposedly estrogenic effect. No evidence of contraindication for breastfeeding. No evidence of contraindications with pregnancy.

How to Combine Milk Thistle

It is believed that milk thistle may disrupt the liver enzyme transport system "cytochrome P450."

Theoretically, the concurrent intake of silymarin and drugs, whose effectiveness relies on the above-mentioned enzyme system, will cause the effect of the latter to be not realized fully or could be suppressed. 

That includes certain blood pressure medicamentations. If you have blood pressure problems, it is best to consult a cardiologist for a clear answer to how you can take silymarin and in what dosage.

What Is the Necessary Dose

There are no scientifically validated optimal doses so far. 

We recommend that you follow the manufacturer's instructions or your doctor’s prescription. 

The usual adult recommended doses range from 160 to 600 mg. extract silymarin daily.

In Which Sports and Nutritional Supplements Can We Find Milk Thistle

Milk thistle extract can be found in the form of a single formula but also in combination with other herbs for sleep and vitamins, antioxidants and complex detoxifying liver supplements.

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 written by 

Brains $ Gainz


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