Forget anthrax and terrorism. Public health experts have uncovered a more pernicious threat to Americans' health and safety the suburbs. According to researchers at the Centers for Disease Control and university public health departments, developers are forcing tens of millions of unwitting Americans into dangerous suburban developments that isolate us from our neighbors, stress us out, make us fat, kill pedestrians, and fill our air with auto-generated smog.
Having declared "sprawl" a public health problem, CDC and other public health experts now want a say in how Americans live, work, and travel. Regardless of whether it's a good idea for public health advocates to have that kind of power, one would at least expect them to provide accurate information about the health implications of how we live. But surprisingly, our nation's health experts have the facts wrong on virtually every claim they make about suburban living and health.
CDC researchers fired the first salvo in the public health community's anti-suburb initiative with "Creating a Healthy Environment: The Impact of the Built Environment on Public Health." The report, paid for by Sprawl Watch, a slow-growth advocacy group, and prepared by Dr. Richard Jackson and Chris Kochtitsky of CDC, claims that suburbs force us to be sedentary, make us fat, and reduce our overall health. However, despite obesity increasing in American society, CDC's own data and other studies show suburbanites are healthier and more active than city dwellers even after accounting for suburbanites' greater wealth and other demographic advantages.
For example, an official CDC report, "Health, United States, 2001," ironically found that suburban women are the group least likely to be obese. Furthermore, a recent study in the American Journal of Public Health concluded that city-dwellers face a greater mortality risk compared to people living in suburbs or rural areas, even after controlling for demographic differences such as age, race, sex, education, income, and marital status.1 The same study also found that suburbanites are the most physically active group.
The Sprawl Watch report also claims suburbs make walking more dangerous. But according to the National Highway Traffic Safety Administration, the pedestrian injury rate from auto collisions dropped 50% for adults and 75% for children between 1975 and 2000, even as millions of people moved to those supposedly dangerous suburbs.
CDC's experts also err in claiming that suburbanization increases air pollution by forcing us to drive. If they'd checked actual air pollution data, they'd know that despite a 75% increase in driving between 1980 and 2000, ozone smog dropped an average of 21%, while airborne particulates declined 33%. Carbon monoxide declined 61%, all but eliminating health concerns for this pollutant.
On-road pollution measurements show that auto emissions are declining by about 10% per year, indicating that air pollution will continue to improve. Technological advances are solving auto pollution without the need to limit people's travel choices.
And rather than being forced, people drive because the automobile can't be beat for convenience and flexibility. Americans use public transit for only about 1% of all travel, and transit's share of travel has been declining for decades, even in densely populated cities with extensive public transit.
After bungling the diagnosis, the public health community has moved into even shakier territory by prescribing dangerous medicine. During a recent CDC-sponsored online conference "Urban Sprawl: What's Health Got to Do with It?" Dr. Jackson, along with a panel of university public health professors, recommended so-called "smart growth" policy measures to mitigate the imagined harm caused by suburban development.2
Smart-growth doctrine includes a suite of policies intended to increase urban population densities, limit expansion of cities, limit or stop road building, and expand public transit. Portland, Oregon comes closest to implementing the smart-growth program and was avidly promoted by the panelists during the CDC sprawl conference.
Portland actually had the greatest decline in housing affordability between 1990 and 2000 of any metropolitan area in the country, while Portland's highway congestion has become the worst among regions its size. And despite building an extensive light-rail system beginning in 1986, transit's market share for work-commute trips in Portland dropped almost 20 percent between 1980 and 2000.3 This doesn't sound like a prescription for greater health and happiness.
Most Americans intuitively realize something the experts apparently don't: In our search for the good life, we must all make tradeoffs among a range of values and desires a larger home and yard, safer neighborhoods, proximity to friends and family, commute time to work, better schools, leisure time, and more. We weigh these options based on our individual tastes and financial means. And for most of us, the outcome of this balancing act includes a preference for a single-family home and travel by car. Given suburbanites' greater health, they seem to know more than the experts about what's in their best interests.
When thinking about why suburbs are so common, public health officials have mixed up cause and effect. People don't live in suburbs because of greedy developers or careless planners. Developers build suburbs because people demand them.
In a dynamic and competitive housing market, developers have a tremendous incentive to find out what combination of amenities will most appeal to homebuyers. If people were clamoring to live in high-rise apartments or condos, developers would build them. Like their customers, developers weigh their options and put together the best package they can, given what they believe their potential customers most value and would be willing to pay.
It's easy to understand why the public health community is so mixed up. They've put knee-jerk anti-suburb ideology ahead of rigorous health research. If health experts really want to improve our lives, they must return to their core mission of protecting Americans from genuine health threats.
We'll always need dedicated health professionals' advice on how our choices might affect our health. But we also deserve a public health community that cares about us enough to respect our choices.
1 J. S. House et al, "Excess mortality among urban residents: how much, for whom, and why?" American Journal of Public Health, December 2000, pp. 1898-1904.
2 CDC and the University of North Carolina School of Public Health, "Urban Sprawl: What's Health Got to Do with It?" An archived video of the conference can be viewed on the Web at www.publichealthgrandrounds.unc.edu/urban/index.html
3 The data for Portland, as well as a wealth of other data on transportation and land use, can be found at www.demographia.com.
