The milk thistle's scientific name is Silybum marianum. It's also known as the Marian thistle, the Mary thistle and the holy thistle. The plant is native to Southern Europe and Asia but has been introduced to many other parts of the world. It belongs to the family called the Asteraceae or the Compositae, which also contains daisies, sunflowers, dandelions and ragweed.
Milk thistle has had a long history as both a food and a medicine. It was once the custom to use the leaves like lettuce, once the spines had been removed. The stalks and roots were also eaten. The seeds were roasted and used like coffee. Eating the plant seems to be less popular today, but researchers do agree that the plant is either nontoxic or has very low toxicity. Since it's a member of the same family as ragweed, however, people who are allergic to ragweed may be allergic to milk thistle.
Evidence suggests that milk thistle may have health benefits, but the evidence is inconclusive at the moment.
- It may be helpful for treating liver problems caused by toxins.
- It may be helpful in protecting the livers of children during chemotherapy treatment.
- Some experiments have shown that milk thistle is helpful for hepatitis (liver inflammation), alcoholic liver disease and cirrhosis of the liver. Some researchers say that these experiments were poorly designed and don't consider the results to be valid, however.
- Milk thistle has been shown to slow the growth of some types of cancer cells in lab equipment and inside the bodies of lab animals, but its effect in humans is unproven.
- In some experiments, milk thistle has been shown to reduce blood sugar, improve insulin resistance and improve the cholesterol profile of people with type 2 diabetes when taken with traditional medication. Once again, however, better quality experiments are needed to confirm these effects.
- Animals studies and some human observations suggest that silymarin can help to counteract symptoms and protect the liver in cases of poisoning by the so-called death cap mushroom (Amanita phalloides). Poisoning by this mushroom is a medical emergency, however. Anybody who has eaten the mushroom must visit a doctor immediately instead of waiting to see if silymarin helps!
It's important that anyone planning to take milk thistle for a medical problem checks with their doctor first. Even safe natural medicines can interact with some traditional medications. In addition, even safe supplements may be a problem when taken in a very concentrated form or in large amounts. Another consideration is that some natural medicines may not be safe for people with certain medical conditions.
Milk thistle photo by Fir0002, CC BY-SA 3.0 License