Mice exposed to a bacterium found in soil navigated a maze twice as fast, and with less anxiety, as control mice, in studies presented yesterday at the 110th general meeting of the American Society for Microbiology in San Diego.

The researchers say we’ve become so urbanized we risk losing a connection with an organism in nature that may actually be beneficial to humans…

Matthews says people are exposed to M. vaccae just by virtue of being outdoors. “It’s only been the last 100 years or so that we’ve become more urbanized and are eating our foods in a different way.”

We no longer eat foods that we grow or gather ourselves, she says – foods that haven’t been “washed multiple times, and dunked in hot water, or processed or grown with pesticides.”