The Link Between an Untreated Infection and Brain Cancer

I recently came across 2 prospective studies suggesting a link between a common parasite and the development of a malignant brain tumor (gliomas). These studies examined the association between antibodies to Toxoplasma gondii and the risk of glioma development. The results of these studies suggest an increased risk of developing a glioma with this parasitic infection, especially in individuals who showed higher levels of antibodies in gliomas.

Toxoplasma gondii is one of the most common parasites in developed countries but most infected individuals have minimal to no symptoms because they have a healthy enough immune system to keep infection at bay.  T. gondii infection, or toxoplasmosis, can alter human behavior. Among other organs, the parasite infects the brain, and it has been blamed for making people more impulsive, and more prone to mental illness, including schizophrenia. The immune system is one of the areas we work with our patients in our approach to cancer. We do a full review of systems to shore up the overall health and address contributing factors to all cancers.

The CDC lists the following as possible sources of infection:

  1. Eating undercooked, contaminated meat or shellfish.
  2. Accidental ingestion of undercooked, contaminated meat or shellfish after handling them and not thoroughly washing hands (especially if you have a cut on your hands).
  3. Eating food with contaminated utensils.
  4. Drinking contaminated water.
  5. Accidentally swallowing residue from cat feces containing Toxoplasma. This is the reason pregnant women are instructed not to clean cat litter boxes.
  6. Mother-to-child (congenital) transmission.

Gliomas are one of the most prevalent types of brain tumors in adults and the National Brain Tumor Society states they make up about 81% of malignant primary brain tumors. While these are the most common type of malignant brain tumors, it is more common to develop metastasis to the brain than be diagnosed with a primary brain tumor.  According to MD Anderson Cancer Center, 150,000-200,000 individuals are diagnosed with brain metastasis each year while only 17,000 individuals are diagnosed with a primary brain tumor. While any cancer can spread (metastasize) to the brain, the most likely cancers are breast, lung, and melanoma. While less likely, colon cancer, gynecologic cancers, and kidney cancer are other cancers that are known to spread to the brain.

As a naturopathic physician who is board certified as a FABNO (Fellow of the American Board of Naturopathic Oncology).  I approach complementary oncology care by utilizing a 3-phase approach. If you imagine the body is like a garden and cancer cells are weeds in the garden. In Phase 1 we investigate why the weeds took over the garden. Cancer is a multifactorial disease process, and, in this phase, we identify and treat all the factors that allowed cancer to grow. In the case of glioma, it may be an unresolved Toxoplasma gondii infection due to a sub-optimal immune system. Standard of care tends to the garden by plucking the weeds out with surgery, spraying them with an herbicide called chemotherapy, or radiating.  Standard of care does a very good job of removing the weeds. While effective, standard of care makes the garden less healthy and viable. This is where phase 2 starts.  Our job is to minimize the side effects of treatment, tie up circulating tumor cells, protect and support the garden, and reduce the risk of metastasis all without hindering the treatment effectiveness. According to a report from the University of Texas Southwestern Medical Center, many cancer patients are taking at least one natural product and NOT telling their oncologist. This is dangerous, may interfere with cancer treatment, and may harm the patient.  Given my training as a resident at Cancer Treatment Centers of America and board certification as a FABNO, I work with my cancer patients to help them through this process without interfering with the standard of care. In Phase 3, we support the garden to help its recovery and stop it from producing so many weeds by treating the multifactorial contributing factors to its specific cancer. 

Whether you are a cancer patient, have a family history of cancer, or someone that wants to reduce your risks of developing cancer, there are many proactive steps you can take. We tell our patients that they are the only person in charge of their health and I work with them to empower them to take charge.

  • CDC – toxoplasmosis – general information – frequently asked Questions (FAQs). (2020, September 03). Retrieved May 04, 2021, from
  • Brain metastases. (n.d.). Retrieved May 04, 2021, from
  • Hodge, JM, Coghill, AE, Kim, Y, et al.  Toxoplasma gondii infection and the risk of adult glioma in two prospective studies. Int. J. Cancer.  2021; 148: 2449– 2456.
  • One-third of cancer patients use complementary and alternative medicine. (n.d.). Retrieved May 04, 2021, from