Smart city planning, experts argue, can help decrease rates of chronic disease
Cars dominate modern cities. Most open spaces are clogged by traffic and parking. Pedestrians are pushed onto tiny pavements or often-unreliable public transport, while cyclists pedal along main streets with little protection from motorised vehicles.
It is no wonder that many commuters choose to sit in private cars, pumping out pollutants, instead of hopping on a bike or walking to a train station.
The authors of a recent three-part series in The Lancet argue this failure in urban planning represents a missed opportunity for public health.
“We have to get from point A to point B,” lead researcher Professor Mark Stevenson, an epidemiologist at the University of Melbourne, tells The Medical Republic.
“If you can actually build exercise into each journey, the return in terms of health benefit is phenomenal.”
Professor Stevenson’s team found that by tweaking a number of factors in urban design, they could increase rates of physical exercise and decrease pollution, with substantial health benefits.
Their model increased density and diversity of land use each by 30% and reduced the average distance to public transport by 30%, while increasing walking and cycling by 10%.
“In order for our cities to survive, moving forward, we cannot have this massive urban sprawl,” Professor Stevenson says. “Cities need to densify in order to provide access to amenities, to public transport and the like.”
In Melbourne, this “compact cities model” led to increased physical exercise, with an estimated reduction of 19% in the burden of cardiovascular disease and 14% in the burden of type 2 diabetes. In London, the reductions were 13% and 7% respectively.
The study also modelled the effects of urban planning interventions in four other cities (Boston, New Delhi, Copenhagen and São Paulo) and found significant health gains in each.
These gains were calculated as “disability-adjusted life years” (DALYs) per 100,000 population, which is the sum of the years of life lost or wasted due to premature death or disability.
These alternative city designs put more people at risk of road trauma, with deaths and serious injuries rising in Melbourne, Boston and London. However, these could be offset by investments in pedestrian and cycling infrastructure, the authors wrote.
“We, as the health fraternity, spend a lot of time and effort around getting people more physically active to reduce the levels of obesity and hence type 2 diabetes,” says Professor Stevenson.
“There is an opportunity to reduce the burden of chronic disease considerably just through design, not through expensive interventions.”
Physical inactivity was responsible for 5.3 million deaths in 2008 alone and cost the global community an estimated US$67.5 billion in 2013.
With more than half of the world’s population living in cities – and rapid urbanisation set to push this to 75% by 2050 – designing walkable and cycling-friendly cities is a powerful strategy for improving health, the authors argue.
But reversing Australian urban planning policies may be easier said than done, Professor Jago Dodson, who was not involved in the study, tells The Medical Republic.
Professor Dodson, the director of the Centre for Urban Research at RMIT University, says Australian governments have traditionally had very little control over land use, which is largely dependent on the interests of private business.
Australian governments have more flexibility in providing public transport, he says. “The problem is that governments – since the Second World War – have preferred to put their budgets into supporting automobile dependence.”
State governments, under pressure from powerful lobby groups, have tended to add road capacity to respond to demand, instead of investing in public transport, he says.
“We haven’t got to the point where we see the automobile or infrastructure industry as being akin to the tobacco lobby.”
Professor Dodson says the era of car-based urban transport policy has been a failure.
“At the moment our public policy across all of government is not rational. We are trying to resolve health problems, yet making them worse through our transport planning.”
Professor Stevenson is more optimistic about the political climate.
“Actually [Australian cities] are moving towards what we have modelled in this paper as it is,” he says. “If you look at Melbourne, that’s exactly what it’s really doing.”
Melbourne is aiming to create a “20-minute city”, whereby people need only travel 20 minutes to a local “hub” to access services and employment, Professor Stevenson says. Sydney is similarly densifying around “nodes”, including Parramatta, Liverpool and Sydney’s CBD.
Australian states are also starting to acknowledge the alignment between urban design and health. For example, the Western Australian government is involved in a web-based initiative, “Healthy Active by Design”, and the NSW government has created a Healthy Urban Development Checklist.
Cities around the world are beginning to adopt these new design principles. The compact cities model is, in fact, based on changes introduced in Zurich, Switzerland, Professor Stevenson says.
After all, there is nothing new about linking health with urban planning.
“City planning was key to cutting infectious disease outbreaks in the 19th century through improved sanitation, housing and separating residential and industrial areas,” co-author Professor Billie Giles-Corti from the University of Melbourne says.
“Today, there is a real opportunity for city planning to reduce non-communicable diseases and road trauma and to promote health and wellbeing more broadly.”
