There are over one hundred trillion organisms- most are bacteria- living in our intestine today. These are referred to as the gut microbiota.
While trillions of bacteria sounds scary, they can actually be very helpful. Research has been done worldwide and the discovery has been that gut microbes actually can kill cancer cells all over the body. (Not just in the intestines) But how? Gut microbes and cancer actually cross paths. Gut microbes can manipulate the immune system and can either increase inflammation or lower it as needed. This means the bacteria can actually work with cancer treatments, boost T-cells, and control other factors that help cancer grow such as fungi, or viruses.
However, this is not all. While some cells help against cancer growth, others do the opposite. It varies cancer to cancer, and all have different results. As said by microbiologist and immunologist Patrick Schloss “What we really need is to have a much better understanding of which species, which type of bug, is doing what and try to change the balance.” So more research is still being done to decide how to control the microbiota, but a possible theory is that because it’s in the intestine it is related to our metabolisms and so what we eat controls the bacterium- this can also then effect the colon, thus effecting more cancer: colon cancer.