Two Major Health Journals Present Special Issues Examining Impact of Built Environment on Health

American Journal of Public Health News Release

WASHINGTON, D.C. (Thursday, August 28, 2003) - People who live in more sprawling areas generally weigh more and are more likely to have high blood pressure, according to a national study released today. The study is the first to link obesity directly to the built environment. It appears in the September edition of the peer-reviewed American Journal of Health Promotion. The American Journal of Health Promotion and the American Journal of Public Health are devoting their September issues to an unprecedented examination of how community design affects health.

"Researchers are finding that sprawl and community design have a direct impact on our health," says Michael Greenberg, PhD, associate editor of the American Journal of Public Health and associate dean of the faculty, Edward J. Bloustein School of Planning and Public Policy, Rutgers University. "These journals present further evidence that we need to strengthen the linkages between planning, design and public health."

For the study, Relationship Between Urban Sprawl and Physical Activity, Obesity, and Morbidity, researchers used Centers for Disease Control and Prevention data to look at health characteristics of more than 200,000 individuals living in 448 U.S. counties in major metropolitan areas. The researchers assessed the degree of sprawl in each county using US Census and other federal data. Sprawl development results in spread-out communities where homes are far from shops, restaurants, or any other destination.

The study shows that, as sprawl increases, so do the chances that residents will be obese or have high blood pressure. People living in the most sprawling counties are likely to weigh six pounds more than people in the most compact county, and are more likely to be obese.

The study also finds that people in sprawling areas walk less. This may indicate that people in more sprawling areas have fewer chances to stay fit through routine physical activity. Distance, lack of sidewalks and other barriers keep them from walking to the store or other destinations. The study controlled for factors such as age, gender, education level, and smoking.

"This study found that as the degree of sprawl increased, so did the odds of being obese or having high blood pressure," says Reid Ewing, PhD, lead author of the study and professor at the National Center for Smart Growth, University of Maryland. "If future research points in the same direction, curbing urban sprawl in favor of compact, walkable communities will become an important strategy for curbing waistline sprawl."

The special issues of the American Journal of Health Promotion and the American Journal of Public Health released today constitute a thorough review of the most up-to-date research on the relationship between community design and health.

"Our primary call to action is that we create communities that encourage and support health promoting behavior," says Richard Killingsworth, MPH, guest editor of the American Journal of Health Promotion and director of Active Living by Design, a program administered by the University of North Carolina.

Among the studies in the American Journal of Health Promotion:

Neighborhood Environment, Access to Places for Activity, and Leisure-time Physical Activity in a Diverse North Carolina Population ­ Researchers surveyed adults in six North Carolina counties to measure the association between environmental factors and leisure time physical activity. The results of the survey indicate that people with access to trails and places to exercise were more likely to engage in recommended levels of physical activity.

Integrating Public Health Objectives in Transportation Decision-Making ­ The paper explores how transportation decision-making can better support public health objectives, including reduced crashes and pollution emissions, and more physical activity. Conventional transportation planning tends to overlook the negative health impacts of increased motor vehicle travel and the potential health benefits from shifts to alternative modes of transportation.

"Land use and transportation policies, while not often associated with the health sector, may nonetheless have important impacts on the health of communities," says Mary Northridge, PhD, MPH, editor-in-chief of the American Journal of Public Health. "More research is needed to better understand how these impacts are distributed among different groups in our society, and how we can better plan our communities to protect and promote the health of all."

Among the studies in the American Journal of Public Health:

Promoting Safe Walking and Cycling to Improve Public Health: Lessons from The Netherlands and Germany ­ Researchers found that American pedestrians and cyclists were much more likely to be killed or injured than were Dutch and German pedestrians and cyclists, both on a per-trip and on a per-kilometer basis. By comparing U.S. statistics and policies to similar statistics and policies in The Netherlands and Germany, the authors conclude that a wide range of measures are available to improve the safety of walking and cycling in American cities, thus reducing fatalities and injuries and encouraging walking and cycling.

Conventional Development Versus Managed Growth: The Costs of Sprawl ­ Researchers found that sprawl, the dominant form of growth occurring in major U.S. metropolitan areas, comes at significant cost to human and natural resources. Sprawl (conventional development) produces a 21 percent increase in amount of land developed and approximately a 10 percent increase in local road lane-miles when compared with smart growth (managed development). Furthermore, sprawl causes about 10 percent more annual public service deficits and 8 percent higher housing occupancy costs. The authors conclude that managed growth can save significant resources with limited effects on traditional development procedures.

Reestablishing Public Health and Land Use Planning to Protect Public Water Supplies ­ Improved land use, design and engineering practices would substantially reduce contamination of major public water supplies according to this new study. Researchers found that high-density per-acre development and engineering controls, along with housing and light commercial activity near main railroads, would substantially reduce runoff.

"We've always known that the environment, including the built environment, affects health, but it is important to know how; that is why the work we are presenting today is so important," says Richard Jackson, MD, MPH, special advisor to the director of the Centers for Disease Control and Prevention.

"The built environment is our most important habitat," notes Allen Dearry, PhD, associate director of the National Institute of Environmental Health Sciences, National Institutes of Health. "It plays a significant role in chronic health conditions such as obesity, asthma, and cardiovascular disease. Communities, biomedical scientists, planners, policy makers, and others need to identify the mechanisms by which the built environment impacts health and develop appropriate interventions to reduce or eliminate its harmful effects."