Having diverse microbes in the gut has been promoted as a way to boost immunity, but studies suggest it’s more complicated than that Having diverse microbes in the gut has been promoted as a way to boost immunity, but studies suggest it’s more complicated than that T he trillions of microorganisms that live in and on our bodies – known as the microbiome – have been hailed as the key to better immunity. “Lots of studies correlate the types of bacteria in your microbiome with health and disease