For more than 40 years, I’ve been fascinated by one question:
Why do some people recover from cancer while others don’t?
That question has taken me around the world, introduced me to some of the brightest minds in alternative medicine, and led me to study subjects most people never even think about.
One of those subjects is parasites.
Now, before you dismiss the idea, hear me out.
I’m not saying parasites cause every case of cancer.
But based on my own observations, the teachers I’ve had the privilege of learning from—including the late world-renowned parasitologist Dr. Hermann Bueno—and what modern research is now confirming, I believe hidden parasites are one of the most overlooked burdens on the immune system.
Dr. Bueno often said that parasites are among the most immunosuppressive things you can have in your body. He also said he had never seen a patient with cancer who also didn’t have parasites. He demonstrated to me the invisible world of parasites and helped solve one of the greatest mysteries of my condition as someone diagnosed with Stage 4 melanoma cancer.
After everything I’ve seen for myself over the past four decades, I’m convinced he was onto something.
In fact, one thing has always struck me as odd.
Why Are Parasites So Often Overlooked?
I’ve always found this interesting.
When a dog, cat, horse, or other farm animal gets sick, one of the first things a veterinarian considers is parasites.
But when people get sick, parasites often don’t even make the list.
Why is this?
After more than 40 years of studying cancer survivors and learning from some of the world’s leading experts on parasites, I’ve come to believe they deserve far more attention than they receive.
The Parasite – Cancer Connection
Researchers have discovered that parasites and cancer cells share several remarkable characteristics. Both can survive by evading parts of the immune system and resisting the body’s normal mechanisms for eliminating abnormal cells. As a result, both can be difficult for the body to completely clear.
The National Cancer Institute admits that certain parasitic worms that are able to live inside the human body can also raise the risk of developing some kinds of cancer. So if you have cancer, it’s quite possible that you may also have parasites.
One of the first things you should do, in my opinion, is to find out what’s bugging you and give them the boot!
Parasites That Have Been Linked to Cancer
One of the best-known examples involves liver flukes.
These tiny parasites can live inside the bile ducts for years, creating chronic irritation and inflammation. Over time, that ongoing damage can significantly increase the risk of bile duct cancer. The connection is so well established that these parasites are officially classified as cancer-causing organisms.
Another example is the blood fluke Schistosoma haematobium.
In parts of Africa and the Middle East, long-term infection with this parasite has been associated with a much higher risk of bladder cancer. Again, the parasite isn’t directly turning healthy cells into cancer. Rather, years of inflammation and tissue injury appear to create an environment where cancer becomes more likely.
Researchers have also found that chronic malaria infection may increase the risk of Burkitt lymphoma, not because malaria itself is cancer, but because it can interfere with the immune system’s ability to keep the Epstein-Barr virus under control.
The common thread running through all of these examples is chronic inflammation and immune disruption.
A Pioneer in Parasite Research
One of the experts who helped bring this overlooked topic into the spotlight is Ann Louise Gittleman, PhD, one of America’s most respected nutrition educators.
In her groundbreaking book, Guess What Came to Dinner?, Ann Louise explores how parasites contribute to digestive complaints, fatigue, skin problems, food sensitivities, and other chronic health issues that often go unexplained for years.
Her goal was simple: to encourage people to consider a possibility that is frequently overlooked and to better understand how supporting gut health may play an important role in overall wellness.
What Can You Do About Those Pesky Parasites?
If parasites are a concern, don’t panic—but don’t ignore them either. Start by educating yourself, work with a knowledgeable healthcare practitioner, and consider a well-designed parasite support program to help eliminate them.
Ann Louise’s book Guess What Came to Dinner? is an excellent place to begin, and her recommended herbal parasite cleanse has helped introduce thousands of people to this often-overlooked aspect of health.
And in my book, I Used to Have Cancer, you’ll find suggested resources beginning on page 165 where you’ll find suggested test kits and cleanses.
Final Thoughts
If parasites are placing an extra burden on the immune system, then identifying and addressing them simply makes good common sense. At the very least, they deserve to be part of the conversation—not overlooked or dismissed.
I’ve learned that some of the biggest breakthroughs often come from asking questions other people aren’t asking. In my opinion, hidden parasites are one of those questions.
Frequently Asked Questions
Can parasites cause cancer in humans?
Yes. Researchers have identified several parasites that are associated with an increased risk of specific cancers in humans. Scientists believe these organisms may contribute to cancer development through chronic inflammation, tissue damage, immune system disruption, and long-term changes in the tissues they infect.
What parasites are linked to cancer?
The best-known examples include liver flukes associated with bile duct cancer, blood flukes associated with bladder cancer, and chronic malaria infections linked to Burkitt lymphoma. Researchers have also documented rare cases involving a dwarf tapeworm whose cancerous cells spread into a severely immunocompromised human host.
How do parasites increase cancer risk?
Researchers believe parasites may increase cancer risk by causing chronic inflammation, repeated tissue injury, immune dysfunction, and long-term cellular damage. Over time, these changes can create conditions that make the development of certain cancers more likely.
Related Articles:
Parasites and Cancer: What Took the World So Long to Catch On?
Parasites: A Hidden Epidemic
Link Between Parasites and Cervical Cancer Discovered
Resources Include:
Gittleman AL. Guess What Came to Dinner? Parasites and Your Health. Square One Publishers; 2013.
Howley PM. Gordon Wilson Lecture: Infectious Disease Causes of Cancer: Opportunities for Prevention and Treatment. Trans Am Clin Climatol Assoc. 2015;126:117-32. PMID: 26330666; PMCID: PMC4530691.
Brindley PJ, da Costa JM, Sripa B. Why does infection with some helminths cause cancer? Trends Cancer. 2015 Nov 1;1(3):174-182. doi: 10.1016/j.trecan.2015.08.011. Epub 2015 Sep 12. PMID: 26618199; PMCID: PMC4657143.
National Cancer Institute. Infectious Agents and Cancer Risk. Available at:
https://www.cancer.gov/about-cancer/causes-prevention/risk/infectious-agents. Accessed June 12, 2026.
Benamrouz S, Conseil V, Creusy C, Calderon E, Dei-Cas E, Certad G. Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa). Parasite. 2012 May;19(2):101-15. doi: 10.1051/parasite/2012192101. Epub 2012 Feb 1. PMID: 22348213; PMCID: PMC3671432.
Çelik F, Şimşek S. Parasite and Cancer Relationship. Turkiye Parazitol Derg. 2022 May
23;46(2):150-162. English. doi: 10.4274/tpd.galenos.2022.30974. PMID: 35604195.
