My microbes
Gut bacteria’s key role in immunity is tuned to the host species, researchers have found, suggesting that the superabundant microbes lining our digestive tract evolved with us — a tantalizing clue in the mysterious rise in human autoimmune disorders. A new study reports that the superabundance of microbial life lining our GI tracts has co-evolved with us. These bacteria, which are essential for a healthy immune system, are ultimately our evolutionary partners. This study, the first to demonstrate that microbes are specific to their host species, also sheds light on the “hygiene hypothesis.” According to this idea, increasingly hyper-hygienic environments might be contributing to a rise in childhood allergies, as these beneficial host-specific microbes are hindered by a plethora of antibacterial home products and cleaning chemicals. “For every cell in your body that is you, that contains your specific genetic information, there are approximately nine foreign bacterial cells, primarily in your digestive tract...