Rural education with a lot of contact with animals has ensured that the immune system and mental resistance to stress are more effective than a city free of pets.
Cows in a field with children
Growth in a rural environment around animals can mean mental improvement.
This was the conclusion of a new research led by the University of Ulm in Germany and now published in PNAS.
This study is by no means the first to suggest that urban growth that lacks microbial diversity can undermine physical health.
In this sense, it is added to the growing evidence in support of the theories that have evolved from the “hygiene hypothesis”.
But the study is the first to suggest that an increased risk of mental disorders, possibly due to an “exaggerated immune response,” may be another unexpected result of growth in an environment less likely to interact with a variety of microbes.
Study co-author Christopher A. Laurie, professor of integrative physiology at the University of Colorado at Boulder, said: “It has been very well documented,” that exposure to pets and rural environments during development is useful to reduce the risk of asthma and allergies later in life. ”
However, he adds, his study also “advances the conversation by showing for the first time in humans that these same estimates are probably important for mental health.”
Loss of contact with advanced microbes
Human existence has become increasingly civilized. In 1950, only a third of the world’s population lived in cities. By 2014, this figure has increased to 54% and is expected to increase to 66% by 2050.
The idea of greater urbanization and changes in lifestyle that accompany it may increase the risk of certain diseases due to the reduced interaction with a variety of microbes derived from the hygiene hypothesis.
The theory is rooted in research 30 years ago that suggests that the low infection rate among young children was the cause of high rates of asthma and allergic diseases in the 20th century.
However, it has become clear that the interaction with microbes exceeds this original range, and has even suggested that the term hygiene hypothesis is an inappropriate name and should be abandoned.
In his article, lead author Stephan or Rieber, a professor of Molecular Molecular Psychology at the University of Ulm, and his team used the term “old friends” to refer to the microbes that evolved with humans.