Microbial ecosystems in the mouth and gut are linked to many ills

“ITHINK IT’S unlikely that any condition in the body is one where the microbiome isn’t involved.” That is the considered opinion of Iain Chapple, one of the speakers at this week’s meeting of the American Association for the Advancement of Science (AAAS), held online this year instead of in Phoenix, Arizona, as originally planned. Dr Chapple was, until 2020, head of dentistry at Birmingham University, in Britain, and is still an active researcher in the field. Mouths are notorious breeding grounds for hostile bacteria, as anyone who has ever had a toothache can attest. But even a healthy mouth is inhabited by lots of bugs (pictured above).

Meanwhile, at the other end of the alimentary canal, the large intestine contains so many microbes that they probably outnumber the cells of the human body. Both bacterial populations have coevolved with their hosts for millions of years, so Dr Chapple is almost certainly right about the intimate connection between them and the body. A pair of sessions at the AAAS discussed some of the latest relevant findings.