Cars vs. health: Lancet series on urban planning, public health

Automobiles—and the planning and infrastructure to support them—are making our cities sick, says an international group of researchers now publishing a three-part series in the British medical journal The Lancet.

University of Washington professors Anne Vernez Moudon and Andrew Dannenberg are co-authors of the first of this series that explores these connections and suggests several planning alternatives for better health.

The Lancet published the series on Sept. 23 and launched it that day during an event at the United Nations General Assembly in New York. Titled, "Urban Design, Transport and Health," the series involved researchers in several nations and fields.

Moudon is a professor emerita of urban design and planning and architecture in the UW College of Built Environments. Dannenberg is an affiliate professor of environmental and occupational health in the School of Public Health and in urban design and planning.

"Most of the negative consequences of city planning policies on health are related to the high priority given to motor vehicles in land-use and transportation planning," said Moudon. "City planning policies supporting urban individual car travel directly and indirectly influence such risk exposures as traffic, air pollution, noise, physical inactivity, unhealthy diet, personal safety and social isolation."

Moudon is second author and Dannenberg a co-author on the first of the three papers, titled "City Planning and Population Health: A Global Challenge." Billie Giles-Corti and Mark Stevenson of the University of Melbourne are lead authors of the series, and Corti is lead on this paper, together with several international experts in public health and transportation planning as co-authors. Over two years, the team reviewed 20 years of literature as well as their own research on the health impacts of city planning through transportation mode choice in cities.

The verdict of their lead article: Automobiles are central to the problem of urban planning and human health.

Individualized motor travel in cities is the "root cause," Moudon and fellow authors write, "of increases in exposures to sedentarism, environmental pollution, social isolation and unhealthy diets, which lead to various types of injury and disease outcomes."

The lead paper suggests eight major interventions that city and transportation planning can employ to make cities more "compact" and promote health.

At the local urban design level, these ideas include walkable and bikable environments, shorter distances to common daily destinations, mixing housing with commercial developments and services and making common destinations more readily available to citizens. Parking demand would be managed by reducing its availability and increasing its cost.

"Together, these interventions will create healthier and more sustainable, compact cities," the authors write, "that reduce the environmental, social and behavioral risk factors that affect lifestyle choices, levels of environmental pollution, noise and crime."

Stevenson is the lead author on the second paper, which focuses on the links between land use, transport and health benefits in compact cities. The third paper, whose lead author is James Sallis of the University of California, San Diego, looks at using science to guide city planning policy and practice for healthy and sustainable cities.

Overall, the series quantifies the health gains that could be achieved if cities incentivize a shift from private car use to cycling and walking, and promote a city model in which employment and amenities—including public transportation—are within walking distance.

Series author Giles-Corti placed the multinational research into historic and global perspective, noting that with world population heading to 50 billion by 2050—and three-quarters of people to be living in cities—city planning must be part of a comprehensive solution to adverse health outcomes.

"City planning was key to cutting infectious disease outbreaks in the 19th century through improved sanitation, housing and separating residential and industrial areas," Giles-Corti said. "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."