The rapid growth of cities brings many challenges. How can we build greener? And how can we support the health and well-being of people living in urban areas?
This seems to involve a trade-off. Many studies show that denser neighborhoods are relatively better for the planet, but have higher risks of depression.
It may not seem surprising that depression is less common in the countryside. Stress, noise, air pollution, loneliness and lack of sunlight on the ground floor of a high-rise apartment are just a few examples of the challenges faced by urban dwellers.
These factors may, in fact, be behind the 39% increase in the risk of depression in urban areas in Western European countries and the US.
But as it turns out, some urban areas are better than others. My colleagues and I produced a new study, published in advances in sciencewhich shows that people in the suburbs are more likely to be depressed than those who live in city centres.
We wanted to discover which factors in the built environment were most important for psychological well-being, so that cities could be better designed to be sustainable and supportive of mental health.
One hectare of land can support the same amount of population as dense low-rise buildings or sparse skyscrapers. Skyscrapers can be in busy, dense business districts or in less dense areas of the city, with high-end apartments facing a big green.
Suburbs, however, tend to have an average density of low-rise buildings. Which approach should we take?
Our team, including researchers from Yale University in the US, Stockholm and Gävle Universities in Sweden, and Aarhus University and University of Copenhagen in Denmark, analyzed a large amount of source material for our study.
Using machine learning tools, we examined satellite images of all buildings in Denmark over 30 years (1987-2017). Then we classify them into different categories depending on height and density.
We combined the resulting map with individual home addresses and health and socioeconomic records in Denmark. This allowed us to take into account known factors that increase the risk of depression, such as socioeconomic status or parents diagnosed with mental illness.
The results do not show a clear correlation that dense urban areas impact depression. This may be because dense urban centers can offer relatively more opportunities for social networking and interaction – which can benefit mental health.
Rural areas also do not appear to increase the risk of mental health problems. Instead, after accounting for socioeconomic factors, the highest risk was found in low-rise, single-family suburbs.
Ultimately, multi-story buildings in central locations or in nearby suburbs with easy access to open spaces – such as green parks or waterfronts – showed surprisingly low risks.
This means that the type of area with a heightened risk of mental health problems typically features medium and low density developments, such as suburban single-family residential areas.
Implications for planning
We believe that the relatively higher risks of depression found in sprawling, low-rise suburbs may be partly due to long car commutes, less open public space, and not high enough resident density to allow for many local business venues where people can congregate, such as shops, cafes and restaurants.
But of course there can be many other factors as well.
That doesn’t mean there aren’t potential benefits to living in the suburbs. Some people may, in fact, prefer privacy, silence and having their own garden.
We hope that this study can serve as a basis for urban planning. The study does not provide support for the continued expansion of car-dependent suburban housing areas if planners are to mitigate mental health issues and climate change.
A better option might be to invest in high-rise housing where lifestyles do not depend on private car ownership, combined with thoughtful spatial design to increase access to waterfronts, canals, lakes or urban parks.
We could also improve the accessibility of existing suburbs to urban services and public open spaces, and ensure that there are more walkable neighborhoods in these car-centric areas.
The research points out how the human being is social. After all, it takes a certain level of density to create living communities that can support shops, businesses and public transport, while also allowing for restoration with the benefit of open space.
In Copenhagen, people grab a beer or pastry and hang out with friends along the canal. These areas are on the fringes of stores and nature – making spaces social. City centers also have less negative impact on climate change than sprawling, car-centric suburbs.
Although the study controlled for income and unemployment, it is crucial to recognize that housing choices are influenced by socioeconomic factors. Properties with a green front or waterfront in central areas are significantly more expensive than houses in the outskirts.
Therefore, taking measures to address the inequality that this can cause, such as creating mixed-income housing projects, is essential to ensure that attempts to use urban planning to improve people’s well-being are inclusive and do not contribute to the gentrification or displacement of low-income communities.
We recognize that the Denmark study findings may not be directly applicable to all other countries. Socio-environmental factors of mental well-being depend on cultural and geographic contexts. However, the framework developed in this study provides a basis for future research in different parts of the world.
Karen Chen, Donnelley Postdoctoral Associate in Geography, Yale University and Stephan Barthel, Principal Investigator of Urban Sustainability, Stockholm University
This article is republished from The Conversation under a Creative Commons license. Read the original article.