If future experiments prove that such genes are essential to the bacterium's happy existence in the gut, then small molecules might be administered to block this pathway and make El Tor's life rather more difficult.

ECONOMIST: The cholera genome

Mathur focused on detecting methane in the breath, since animal studies found that the presence of a certain family of organisms called archaea, which are older than bacteria and colonize the gut, was linked with weight gain and conveniently released small amounts of methane gas.

CNN: Can you smell obesity?

His new shrunken stomach was then attached further down his small intestine, to a section known as the ileum which secretes a different gut hormone, PYY, which is responsible for making you feel full.

BBC: The second brain in our stomachs