The role of the microbiome in human health and disease: an introduction for clinicians

Research into the microbiome-the indigenous microbial communities (microbiota) and the host environment that they inhabit-has changed clinicians' ideas about microbes in human health and disease. Perhaps the most radical change is the realization that most of the microbes that inhabit our body supply crucial ecosystem services that benefit the entire host-microbe system. These services include the production of important resources, bioconversion of nutrients, and protection against pathogenic microbes. Thus disease can result from a loss of beneficial functions or the introduction of maladaptive functions by invading microbes. This review will show how an understanding of the dynamics and function of the…