The rapid growth of cities comes with 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 more populated neighborhoods are relatively better for the planet, but come with a higher risk 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 actually be behind the 39 percent increased risk of depression for urban areas in Western European countries and the United States.
But as it turns out, some urban areas are better than others. My colleagues and I conducted a new study published in Scientific progressindicating that people in the suburbs are more likely to be depressed than those in urban centers.
We wanted to understand which factors in the built environment are most important for psychological well-being so that cities can be better designed to be both sustainable and supportive of mental health.
One hectare of land can house the same amount of population with dense low-rise or sparse high-rise buildings. High-rises can either be in dense busy business districts or in less dense urban areas with luxury apartments facing large green areas.
Suburbs, however, tend to have a medium density of low-rise buildings. What approach should we take?
Our team, including researchers from Yale University in the US, the Universities of Stockholm and Gävle in Sweden, and the University of Aarhus and the University of Copenhagen in Denmark, looked at a very 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). We then classified them into different categories based on height and density.
We combined the resulting map with individual residential addresses and health and socioeconomic registers in Denmark. This allowed us to account for known factors that increase the risk of depression, such as socioeconomic status or parents who have been diagnosed with mental illness.
The results did not show a clear link that dense urban areas influence depression. This may be because densely populated urban centers may provide relatively more opportunities for social networking and interaction – which may benefit mental health.
Nor did rural areas appear to increase the risk of mental health problems. Instead, after accounting for socioeconomic factors, the highest risk was found in suburbs with low-rise and single-family housing.
After all, high-rise buildings in central locations or in nearby suburbs with easy access to open spaces – such as green parks or coastlines – show surprisingly low risks.
This means that the type of area at increased risk for mental health problems typically includes medium-density, low-rise buildings, such as single-family suburban areas.
Implications for planning
We believe that the relatively higher risks of depression found in sprawling, low-rise suburbs may be due in part to long car journeys, less public open space, and not high enough resident density to enable many local commercial places where people can gather, such as shops, cafes and restaurants.
But, of course, there could be many other factors as well.
That’s not to say there aren’t potential benefits to living in the suburbs. Some people may actually prefer privacy, quiet and their own garden.
We hope that this study can be used as a basis for urban planning. The study provides no support for the continued expansion of car-dependent suburban single-family residential areas if planners are to mitigate mental health and climate change issues.
A better option could be to invest in high-rise residential buildings, where the lifestyle does not depend on owning a personal car, combined with thoughtful spatial design to increase access to shorelines, canals, lakes or city parks.
We could also improve existing suburbs’ access to both city services and public open spaces, and ensure there are more walkable neighborhoods in these car-centric areas.
The research shows how social people are. A certain level of density is, after all, necessary to create vibrant communities that can support shops, businesses and public transport while allowing regeneration with the benefit of open space.
In Copenhagen, people take beer or pastries and hang out with friends along the canal. These areas are on the fringes of both shops and nature – making the spaces social. City centers also have less of a negative impact on climate change than sprawling, car-centric suburbs.
Although the study controls for income and unemployment, it is critical to recognize that housing choices are influenced by socioeconomic factors. Properties with water or greenery in the central parts of the city are significantly more expensive than houses on the outskirts.
So taking action to address the inequality it 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 results of the Danish study may not be directly applicable to all other countries. Socio-ecological determinants of mental well-being depend on cultural and geographical context. However, the framework developed in this study provides a basis for further research in different parts of the world.
Karen Chen, Donnelly Postdoctoral Fellow in Geography, Yale University and Stefan Bartel, Principal Researcher in Urban Sustainability, Stockholm University
This article is republished from The Conversation under a Creative Commons license. Read the original article.