It’s estimated that approximately 1000 different species of bacteria are included in the 1 billion microorganisms that live on each square centimeter of our skin. It is now becoming quite clear that the skin microbiome (collective set of microorganisms and their genetic material) modulates skin diseases, influences metabolic processes and is important for skin immunity. The diversity of the skin microbiome is influenced by various factors including transient microbes, genetic predispositions, location and environmental characteristics.
In 2007, the National Institute of Health provided funding for a Microbiome Project Consortium to characterize the human microbial communities present at specific body locations including skin. Recent advances in the molecular analysis of skin microbes revealed a greater diversity of skin bacteria than had been found previously using culture-based methods that were limited by the difficulties of growing certain species in the laboratory. It is now known that the microenvironment of skin characterized by sebum, moisture and hair follicles is highly associated with a bacterial community that is either commensal (does no harm) or symbiotic (mutually beneficial). In fact, many beneficial bacteria protect our skin from dangerous pathogens.