There are 10-100 trillion non-human cells (mostly bacteria) that reside in/on the human body; this is the human microbiome. Human microbiome is now the hottest area of basic and clinical research with an explosion in the number of published research articles and patents within the past Decade.
Results from studies are forcing researchers and clinicians to re-evaluate definition of what is a human being and the importance of microorganisms to human health.
Links to the microbiome are emerging to asthma, neurological health, obesity, autoimmune disorders, bone health, healing, various cancers, etc.
The Human Microbiome Project was established in 2008 to enable the comprehensive characterization of human microbiome and its role in human health and disease.