LICHTMAN: "Is there evidence to suggest that it's better...to live among a lot of microbes in your house?"
DUNN: "Yes... we have a series of interesting anecdotes....
"...There's... a study in Finland... led by Ilkka Hanski, and this study looked at adolescents in houses that differed in which plant species they had in their backyard.
And those adolescents who grew up in houses with more native plants in their back yard had different microbes on their skin and were at a much reduced risk of allergy."
"There's a study from Detroit that suggests that pregnant mothers who live in houses with a dog are less likely to show evidence in their umbilical cord blood of the kinds of antibodies we associate with allergies.
It's also been shown that young children growing up with dogs are less likely to develop wheezing and asthma. And so in both cases it's been suggested... that in those houses, those children and the fetus are being exposed to more kinds of bacteria that... prime their immune system and make their immune system function more normally.
...I think it's interesting to speculate... that... what we're seeing in houses with dogs is... this additional connection to a broader nature... that as we move into more and more urban environments where... we experience a diversity of microbes less and less, that any of these mechanisms that connect us to more microbial species provides some health benefit.
# # #
More details of Finland study here.
Read The wild life of our bodies, by Rob Dunn.