Milk Thistle, a purple-crowned herb, packs a medicinal punch against numerous conditions including type 2 diabetes, kidney disease, gallbladder disorders, high cholesterol, cancer, and liver diseases such as cirrhosis, jaundice, and hepatitis. The plant’s active compounds — silibinin, silydianin, and silychristin — which are most concentrated in the seeds of the plant, are found in a standardized extract known as silymarin.
Milk thistle (Silybum marianum) is native to Europe, but now grows wild within the United States and certain areas of South America. Its medicinal benefits have been revered for over 2,000 years — the Romans having utilized it as a liver protector as early as the first century. The herb’s name is derived from the milky white liquid that leaks from its leaves when they are crushed. Scientific analysis of milk thistle has demonstrated its efficacy in a range of diseases.
Liver Health And Defense
Milk thistle’s antioxidant, anti-inflammatory, and anti-cancer properties combine to defend the liver from an onslaught of environmental threats. A healthy liver is paramount to human health, since the organ is responsible detoxification. The liver’s function is to filter the blood in order to clear the body of toxins derived from pollution, poor diet, alcohol intake, among other things.
A paper titled “Milk thistle in liver diseases: past, present, future” explains that the active complex, silymarin, may also act as a toxin blockade and has also been shown in animal models to protect the liver against damage caused by radiation, iron overload, alcohol, acetaminophen (Tylenol), and carbon tetrachloride (a potential carcinogen found within both ambient indoor and outdoor air).
As well as potentially offering preventative defense, milk thistle may also be able to assist in cases where liver disease has already manifested. Silymarin may be useful in the treatment of non-alcoholic steatohepatitis (NASH). This condition is caused by an accumulation of fat in the liver, which results in inflammation that can eventually lead to the formation of fibrous scar tissue — a condition known as cirrhosis. A paper titled “Silymarin in treatment of non-alcoholic steatohepatitis: A randomized clinical trial” documents a study conducted on 64 patients suffering from NASH. The authors state that, “The results confirmed that silymarin could help the patients with NASH in lowering their hepatic enzymes particularly ALT [alanine aminotransferase] so, it is useful for the treatment of NASH.”
Although most of the research has been conducted upon either cell cultures or animals, the results are signaling that compounds within milk thistle may be effective against cancer. An article published by the University of Maryland Medical Center explains that early laboratory studies have shown silymarin and other substances within milk thistle may exert anti-cancer activity by stopping cancer cells from dividing and reproducing, and by shortening the lifespan of cancer cells and reducing blood supply to tumors. A paper entitled “Advances in the use of milk thistle” authored by researchers from the University of Minnesota states, “There is strong preclinical evidence for silymarin’s hepatoprotective and anticarcinogenic effects, including inhibition of cancer cell growth in human prostate, skin, breast, and cervical cells.”
Another paper, authored by a team from the University of Tehran, states that silibinin has been shown to have dramatic anti-proliferative effects against different types of malignant cell lines. The paper documents a study that tested silibinin on prostate cancer cells. The team concluded that, “silibinin can probably inhibit metastasis” in prostate cancer.
A University of Colorado study suggests silibinin is able to kill skin cells that have mutated due to the harmful effects of UVA radiation. Rajesh Agarwal, PhD, co-program leader of Cancer Prevention and Control at the Colorado University Cancer Center explains, “When you have a cell effected by UV radiation, you either want to repair it or kill it so that it cannot go on to cause cancer. We show that silibinin does both.” Agarwal continues, “When you take human skin cells — keratinocytes — and treat them with silibinin, nothing happens. It’s not toxic. But when you damage these cells with UVA radiation, treatment with silibinin kills the cells.”
A second study on skin cancer, published in the journal Molecular Carcinogenesis, showed that silibinin protected mouse skin cells against UVB, another type of radiation emitted by the sun. The authors stated that their findings suggest that, “the use of silibinin in UVB-damaged human skin would also be a practical and translational strategy to manage solar radiation-caused skin damages as well as skin cancer.”
More proof that milk thistle derived compounds may assist in the treatment of cancer comes in the form of a publication from Case Western Reserve University in Cleveland. This document describes the anticarcinogenic effect of silymarin on human breast cancer cells. The authors state, “Silymarin treatment resulted in a significantly high to complete inhibition of both anchorage-dependent and anchorage-independent cell growth in a dose- and time-dependent manner.”
Research is showing milk thistle may be able to help control diabetes, a condition that 1.4 million Americans are diagnosed with every year, thanks once again to silymarin. A team from the Institute of Medicinal Plants in Tehran, found that silymarin may help to control blood sugar in those suffering from type 2 diabetes. Their study involved 51 adults, 25 of which received three doses of silymarin daily over four months alongside conventional therapy. The remaining control group of 26 received the same therapy, but were given a placebo instead of the milk thistle extract. At the end of the study period, the group that consumed the silymarin displayed improved blood sugar control, and cholesterol and triglyceride levels. In a news release regarding the study, one of the researchers, H. Fallah Huseini, PhD, explained, “We don’t know the exact mechanism of action for this effect, but this work shows that silymarin could play an important role in treating type 2 diabetes.”
Alzheimer’s is a feared disease that can rob its victims of cognitive function and memory. It’s associated with a build up of protein deposits in the brain called beta-amyloid plaques. A study on the effects of silymarin on Alzheimer’s Disease using a mouse model, which was conducted by a team from the Tokyo Metropolitan Institute of Gerontology in Japan, found silymarin to be a “promising agent” for the prevention of Alzheimer’s Disease.
How To Take
Milk thistle can be taken in a multitude of ways such as tablets, tinctures, teas, capsules, and oils. Varying doses are recommended depending on specific conditions and it should be noted that there are contraindications with certain conditions. Always read product labels to ensure milk thistle extracts are safe for you to consume. With regards to the following conditions, the Mayo Clinic recommends the following doses for adults 18 & over:
For acute viral hepatitis: 160-800 milligrams of silymarin taken by mouth daily in three divided doses for three weeks.
For allergic nasal symptoms: 140 milligrams of silymarin taken by mouth three times daily for one month.
For antioxidant effects: 140 milligrams of silymarin taken by mouth three times daily for three weeks.
For cirrhosis: 160-800 milligrams of silymarin taken by mouth in 2-3 divided doses daily by mouth for up to two years.
For diabetes (type 2): 200-230 milligrams of silymarin taken by mouth one to three times daily for four weeks to 12 months, together with regular therapy.
For diabetic nephropathy (kidney disease): 140 milligrams of silymarin taken by mouth three times daily for three months.
For liver damage from drugs or toxins: 160-800 milligrams of silymarin taken by mouth daily in three divided doses for periods ranging from 15 days to five weeks or 70 milligrams of silibinin taken by mouth three times daily for 6-12 months.
For high cholesterol: 200-600 milligrams of silymarin taken by mouth once or three times daily for four months in addition to standard therapy.
For chronic liver disease: 160-480 milligrams of silybin taken by mouth once or three times daily for up to three months or 120-420 milligrams of silymarin taken by mouth daily in three divided doses for four weeks to 12 months.
For osteoarthritis: 150 milligrams of silymarin taken by mouth twice daily for eight weeks.
For radiation skin irritation: a silymarin-based cream applied to the skin.