Country dwellers richer in immune-calming bacteria
Children who grow up close to nature may have fewer allergies because of protective skin bacteria.
That finding is a new twist on the hygiene hypothesis, the idea that contact with bacteria early in life is crucial for the development of the human immune system. Skin microbes tied to the diversity of the natural environment seem to teach the body to calm allergic responses, researchers report online the week of May 7 in the Proceedings of the National Academy of Sciences.
“Here is yet another reason for planning green spaces in towns and cities,” says Ilkka Hanski, an ecologist at the University of Helsinki in Finland.
The decline of biodiversity in urban areas might damage the health of city dwellers by annihilating some of humankind’s tiniest allies, Hanski and his colleagues suggest. The researchers studied 118 Finnish adolescents who had lived their entire lives in a single place: a small town, a village or a house by itself