Our planet is fast becoming an urban one. At the beginning of the 21st century, most of the world’s population still lived in the countryside, but by 2050, more than 70% of us will be city dwellers. Across the world, many cities are struggling to keep pace and to offer a healthy environment for their booming populations.

5546According to the United Nations, around 1 billion people worldwide live in slum conditions, with inadequate sanitation or water, poor access to healthcare, and an increased risk of infectious disease. In the developed world, city lifestyles bring huge health challenges, including obesity, diabetes, higher stress levels, and associated mental ill-health. Then there’s the growing air pollution problem, which the World Health Organisation says is now the world’s greatest environmental health risk, linked to one in eight of total global deaths.

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Yet busy urban life doesn’t necessarily have to mean poor health. Densely populated Hong Kong, Osaka, Tokyo, and Singapore top global health lists, thanks to accessible healthcare and ease of travel.

In some world’s biggest cities, urban populations live longer than their national average. From India to the US And across the globe, efforts are being made to promote healthier cities, whether through better infrastructure, greener transport options, or better urban design.

Dr. Laurence Carmichael, senior lecturer at the University of the West of England and head of the WHO Collaborating Centre for Healthy Urban Environments, says the drive to improve urban living needs to address a wide range of different local factors – but cities, as “hubs of innovation,” are attempting to rise to the challenge.

“That wwho are less developed worldwide have to start with issues like sanitation, water quality and drainage, then as their systems become more sophisticated, they can start thinking about things like food systems, green infrastructure, and adapting their cities for all ages,” she says. “Many of us live in areas that are already developed, and we need to retrofit health qualities into that environment. It’s not just whether you are physically active but whether you are doing that in a place that makes you feel good

Helen Wilding

The way a city is laid out is increasingly being seen as key. Carmichael cites the example of Freiburg in Germany, where elements like cycle networks, public transport, and new neighborhoods are all planned to promote not only environmental sustainability but better quality of life and public health. And it’s not just a European phenomenon: the WHO singles out Curitiba in Brazil as an example of a city where good urban planning contributes to higher life expectancy and relatively low infant mortality.

The Healthy Cities Network, part of the WHO’s global urban health movement, has around 27 member towns and cities working to promote better health in the UK. Network coordinator Helen Wilding says urban leaders increasingly recognize the vital role they can play in delivering healthier communities.

“There is a more conducive atmosphere to talking about how the different functions of a local authority impact on the health of a city,” she says. “There’s a lot of interest in thinking about urban green space and the public realm and what that means for mental wellbeing. So it’s not just whether you are physically active but whether you are doing that in a place that makes you feel good.”

In Newcastle, where Wilding is based, the council looks to embed public health in every area of its work. “It’s not just about focusing on behaviors – saying don’t smoke, eat better, do more exercise – but actually looking at the environment and the way that can influence people’s choices,” says Jane Streather, Newcastle’s cabinet member for public health and housing.

“In cities, we have a legacy of a built environment which we have to adapt, and we are very conscious of how our policies impact on people’s wellbeing. We can learn from each other here and internationally.”

But, as Streather stresses, tackling the root causes of ill health means addressing inequality and poverty. That’s a challenge worldwide: according to a recent UN-Habitat report, 75% of the world’s cities have higher levels of income inequalities than they did two decades ago. That wealth gap can have a dramatic impact on the health and life expectancy of communities living just a few miles apart as the WHO has highlighted, in Nairobi, a child who lives in a slum is four times more likely to die before the age of five than a child in another part of the city. Here in the UK, Scotland, particularly Glasgow, has the lowest life expectancy and the widest mortality inequalities in western Europe.

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New research suggests a “toxic combination” of poor urban planning and political decisions at a local and national level on top of high levels of poverty and deprivation have contributed to this “Glasgow effect” (pdf). The report’s author, Dr. David Walsh from the Glasgow Centre for Population Health, says economic factors are crucial to population health – but widening inequality suggests politicians have not yet learned from past failures.

“We have seen staggering widening inequality in income terms and therefore health terms,” he says. “There is a danger that some of the policies currently being pursued, like welfare reform and taxation policies, are furthering that inequality and that areas with higher levels of disadvantage and poverty will do worse again.”

Issues of fairness are, for many, at the heart of healthy cities – not only in tackling the inequalities in income, services, and basic infrastructure that contribute to poor health but also in creating cities that work for all of their citizens. Dan Masterson is a healthy urban planning officer at Stoke-on-Trent, one of the UK healthy cities. The approach to urban health encompasses everything from proactive healthy living projects to better urban design. He says a truly healthy city works for all of its citizens. “A healthy city is somewhere walkable and permeable. It’s about putting the human before the car, but also about tackling issues like social isolation and being age-friendly. It’s about equity.”