Milk Thistle and Pancreatic Cancer Prevention: The evidence thus far
Source: Iran Journal of Basic Med Sci (Oct 2022)
Lifestyle Medicine Update (November 12, 2023)
Many people are aware that the seeds, leaves and fruits of the Milk thistle plant contain unique constituents that are shown to help protect and repair liver damage that occurs under certain conditions. These unique Milk thistle constituents known as Silymarin (flavonolignans) also help to support liver detoxification function. Some human studies have shown that Milk thistle supplementation has been beneficial in cases of viral hepatitis, alcohol-induced liver damage, and in liver toxin damage, showing objective improvement on blood tests such as a decrease in liver enzymes (i.e., aspartate aminotransferase) that are used to tract various liver diseases. But recent experimental studies have shown that Milk thistle also shows promise as an agent that may help to block steps in the development of certain cancers, particularly pancreatic cancer, prostate cancer, liver cancer and skin cancer. This evidence is thoroughly reviewed in the 2022 publication in the Iran Journal of Basic Medical Science. I think this review article is important because pancreatic cancer is the fourth leading cause of cancer death in both men and women. In the United States the 5-year relative survival rate for pancreatic cancer is only 12%, making it a very lethal form of cancer. (https://www.cancer.net/cancer-types/pancreatic-cancer/statistics). Not a lot of progress has been made in curing this condition.
As reviewed by these researchers Milk thistle has been shown to block key events in pancreatic cells that lead to the development of pancreatic cancer. As they explain, pancreatic cancers begin from non-invasive masses, usually pancreatic intraepithelial neoplasias (precancerous lesions). These cancers may develop from intraductal papillary mucinous neoplasms or mucinous cystic neoplasms that are easily detected upon screening by an abdominal ultrasound or MRI. In animal models Milk thistle (silymarin) supplementation has been shown to decrease severity of pancreatitis in mice who were given chemicals (cerulein) to induce pancreatitis. Pancreatitis is a key risk factor for future development of pancreatic cancer in humans. As well, Milk thistle (silymarin) applied to human pancreatic cells induces DNA damage to these cells, causing cell suicide known as apoptosis (via caspase 3/7mediated apoptosis). Milk thistle (silymarin) also inhibited a key cancer gene (c-MYC) that promotes pancreatic cancer when applied to human pancreatic cells in experimental studies. Other experiments show that Milk thistle (silymarin) blocks pancreatic cells from dividing and multiplying (via G1 phase cell cycle arrest and inhibiting cyclin kinase activity). Milk thistle has also shown an ability to cause cell suicide of a various human pancreatic cell lines (AsPC-1, BxPC-3, Panc-1 cells) in experimental studies.
I’m not saying that Milk thistle is the single answer to prevent pancreatic cancer, as there are established risk factors for this disease that you should know about, some of which can be addressed via diet and lifestyle. The established risk factors for pancreatic cancer, as outlined by the American Cancer Society, include:
Type 2 Diabetes
Workplace exposure to certain chemicals used in dry cleaning and metal working industries.
Age – as you get older the risk increases
Race – African Americans are slightly more likely to develop pancreatic cancer than whites.
Family history, but most people who develop pancreatic cancer have no family history of the disease.
There are some inherited gene mutations, which account for about 10% of all pancreatic cases (i.e., BRAC1 or BRAC2, PALB2, P16/CDKN2A, PRSSI, MLH1 or MSH2, STK11)
There is emerging evidence around diet and lifestyle as well, which include:
The regular consumption of red and processed meats (such as sausage and bacon) and saturated fats may increase the risk of pancreatic cancer. Sugary drinks may also increase the risk. More research is needed in this area.
Moderate to Heavy Alcohol Consumption (the evidence is quite convincing)
Infections such as H. pylori and Hepatitis B increase the risk of developing pancreatic cancer. But more studies are needed to clarify this risk. (American Cancer Society Pancreatic Cancer Risk Factors https://www.cancer.org/cancer/types/pancreatic-cancer/causes-risks-prevention/risk-factors.html)
So, its important to be cognizant of all these risk factors and to do your best to modify your lifestyle to reduce your risk of modifiable risk factors, such as smoking, weight gain, alcohol consumption etc. Can taking a Milk thistle supplement each day be an adjunct measure to help reduce pancreatic cancer. The experimental evidence argues quite strongly for this effect, as well as its potential preventive effects for prostate, liver, and skin cancers. Because our liver detoxification enzymes become more sluggish as we age and our immune system becomes weaker, my feeling is that everyone 50 years and older should consider taking a supplement each day, as I do, that contains:
Milk thistle (standardized to 80% silymarin content)
Indole-3-Carbinol (derived from cruciferous vegetables)
Reishi mushroom extract
These four natural agents work synergistically to support liver detoxification function and immune system function. The secondary benefits of Milk thistle in a formulation like this may also help to prevent and/or reverse some existing liver damage (from drugs, alcohol, toxins, infection) and help block important biological steps in cancer development withing certain organs and tissues. So, this is something to consider and to investigate further in my view.
I have included the references on Milk thistle and cancer and Milk thistle and liver conditions in the text below.
Emadi S. A. et al. A review of therapeutic potentials of milk thistle (Silybum marianum L.) and its main constituent, silymarin, on cancer, and their related patents. Iran J Basic Med Sci. 2022; 25(10): 1166-1176. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9588316/#:~:text=the%20pancreatic%20carcinoma-,AsPC%2D1,-%2C%20BxPC%2D3%2C%20and
Mulrow C. et al. Milk Thistle : Effects on live disease and cirrhosis and clinical adverse: Summary. AHRQ Evidence Reports Summaries (2000). https://www.cancer.org/cancer/types/pancreatic-cancer/causes-risks-prevention/risk-factors.html
Eat Smart, Live Well, Look Great,
Dr. James Meschino
ABOUT THE AUTHOR
Dr. James Meschino, DC, MS, ROHP, is an educator, author, and researcher having lectured to thousands of healthcare professionals across North America. He holds a Master’s Degree in Science with specialties in human nutrition and biology and is recognized as an expert in the field of nutrition, anti-aging, fitness, and wellness as well as the author of numerous books.