The human gut hosts an array of bacteria that conduct many immune and metabolic functions. The co-evolution to the immune system and microbes of the gut is the topic of interest for cancer and nutraceutical research. The environmental and biological factors that impact gut diversity can also lead to the development of intestinal dysbiosis. The incorporation of nutraceuticals like polyunsaturated fatty acids, phytochemicals, and probiotics into the host diet can aid in the prevention of cancer and the reduction of cancer treatment related symptoms.