Could the key to your health be contained in the trillions of microorganisms that live harmoniously on your body and in your gut? Research is beginning to reveal that intestinal bacteria can influence your body's ability to respond to cancer treatment, fight infection, and even prevent disease ever from happening. The body's microbiome could represent the missing link between why immunotherapy treatments, like that which won the 2018 Nobel Prize for medicine, can cure cancer for some people and not others.