It's the first time in history that more people are living in cities around the world than in country and rural areas. Currently, over 54% of us reside in the hustle bustle of city life. It's predicted that by 2040, it will be over 70% of the global population.
It's important for us to recognise the pressure that exists from living in a city, and as the population increases, so will the sensory experience of living in a confined area. Traffic noise, pollution and peak hour are only set to increase as more people move into the urban built environment.
Research conducted by Dr. Andreas Meyer-Lindenberg of the Central Institute of Mental health in Mannheim, Germany, found that the brain of urban or city based people is more inept at handling stress compared to those in the country.
This is thought to be attributed to the constant state of alertness whereby the human sensors of touch, sound, sight, and smell are constantly being bombarded.
When this happens, the two regions of the brain which are most associated with stress, the amygdalae, and the perigenual anterior cingulate cortex, become activated. Even the smallest sound like a car horn will activate the body's fight or flight mechanism. Humans often forget they are animals and have inbuilt sensory warnings to save them from potential danger. When this happens constantly, the release of adrenaline and cortisol through the body means that somebody who lives in the city is usually stressed, even if they don't realise it.
This type of stress may not present itself in a traditional way, but rather, a city person is more likely to get stressed over a small stressor than a country person. The ability to cope with stress is weakened when continual stress occurs.
It doesn't just stop there for city dwellers, the report also goes on to determine people in the city are 21 percent more likely to have anxiety disorders and there's also a 39 percent increase in mood disorders. Part of these mental health disorders are thought to be due to overcrowding, and you guessed it, constant exposure to sound.
The brain interprets constant sound as a lack of control, which can increase anxiety. This is then added to the number of people around which adds to an already heightened level of stress.
Stress can affect sleep, leading to chronic fatigue. A lack of sleep not only affects work performance but immunity, mood and can even lead to more harmful medical conditions such as diabetes and cancer.
Constant stress is also very dangerous for heart health. Cortisol, when released properly, doesn't harm the body, but an overdose of cortisol can be very harmful to keeping the heart healthy and free from plaque.
All this research shouldn't keep us from living in the city, after all, there are many positives to living close to a city center. It does remind us though that we need to do everything we can to protect ourselves from the sensory overload in the big smoke.
How can we limit our contact with technology? How can we safeguard our home and office against constant noise? Do you have strategies in place to help you relax?
As the city grows, it's hard to believe the type of increased health risk which will grow with it.