What are the consequences of the disappearing human microbiota?

Department of Medicine and the Department of Microbiology, New York University Langone Medical Center, New York, New York 10017, USA.
Nature Reviews Microbiology (Impact Factor: 23.32). 11/2009; 7(12):887-94. DOI: 10.1038/nrmicro2245
Source: PubMed

ABSTRACT Humans and our ancestors have evolved since the most ancient times with a commensal microbiota. The conservation of indicator species in a niche-specific manner across all of the studied human population groups suggests that the microbiota confer conserved benefits on humans. Nevertheless, certain of these organisms have pathogenic properties and, through medical practices and lifestyle changes, their prevalence in human populations is changing, often to an extreme degree. In this Essay, we propose that the disappearance of these ancestral indigenous organisms, which are intimately involved in human physiology, is not entirely beneficial and has consequences that might include post-modern conditions such as obesity and asthma.

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