Cities are dynamic and stimulating places, but their residents have a much higher rate of mental illness than the rest of the population.
We have known for a long time that the environmental context determines our health, and we have developed a lot of attention not to expose ourselves too much to risk factors (polluted air or water, too much sun, etc.). The idea that the external environment influences our psyche has also been known for a long time: from the first research dating back to the 1930s to current studies, researchers from all over the world have discovered what problems Mental disorders of all sorts are more common in densely populated cities than in rural areas.
In the city you have 40% more risk of depression, 20% more risk of anxiety and double the risk of schizophrenia
The causes
There is something in the very nature of cities that seems to interfere with the mental well-being of their inhabitants. The first "multidisciplinary" studies of the phenomenon date back to a few years ago: "it is an emerging field of study," he says Andreas Meyer-Lindenberg, director of the Mental Health Center in Mannheim, Germany.
Meyer-Lindenberg and her research partner, environmental scholar Matilda van den Bosch of the University of British Columbia in Vancouver, have recently identified a spectrum of substances and situations abundant in cities that "bombard" people every day and are the contributing cause of onset of mental disorders.
More livable cities equal healthier minds
A fundamental part of collective psychological improvement is closely linked to the livability of cities: this is what was concluded in study that Meyer-Lindenberg published onAnnual Review of Public Health: it is a crucial factor if you consider that half of the world's population lives large city and percentage is set to rise to 70% within the next 30 years.
“Globally, urbanization is increasing exponentially:
Marianthi-Anna Kioumourtzoglou, assistant professor of Environmental Sciences at Columbia University
we must necessarily redesign our cities in a way that respects our psyche”
The risks around us
In their study Meyer-Lindenberg and van den Bosch reviewed many substances and factors "suspected" of having an influence. Some (like pollen) do not they show enough correlations with depression. Others have a direct correlation such as heavy metals (lead above all), pesticides, bisphenol A (plastic, food containers, even baby bottles!), and noise pollution.
We are (also) what we breathe
Data from different disciplines all converge on the identikit of the main "killer": air pollution is linked not only to lung and heart problems that kill million people every year, but is associated with anxiety, depression, paranoia and psychotic phenomena.
It is clear that living in the city does not put us directly and certainly on the path of madness, the researchers specify: mental disorders arise from a complex interaction of genetic predispositions, personal events and environmental factors. What is certain is that the risk increases considerably and proportionally to crowding and pollution in urban areas.
How this "induction" occurs is not yet entirely clear: some studies show that the environment damages us on a neuronal or chemical level, altering the relationship with crucial substances such as serotonin: in younger people they would prevent the its normal production.
The force of nature
On the contrary, studies show the positive impact of a more natural context: research in this regard is many and extensive. In a recent study, scientists verified how contact with a natural environment reduces the recurrence of obsessive thoughts that cause anxiety and depression. Same thing as far as it concerns the walks in natural contexts, which calm brain activity in regions such as the perigenual anterior cingulate cortex, involved in the regulation of emotions and main "victim" of many substances among those examined.
What to do?
About one in five adults in the US lives with a mental disorder, with depression ranked as the world's leading cause of distress by the WHO. This makes it very important to understand how the world around us deforms our mind: in this way politicians and urban planners will be able to promote incentives for a more natural lifestyle and more targeted restrictions on polluting factors.
