Study links community sprawl to fat

Here's one reason to leave the suburbs and move back to Baltimore: It could make you thinner.

A national study of almost 450 communities released yesterday found that people who live in sprawling areas tend to weigh more and are more likely to have high blood pressure than urban dwellers.


"When U.S. adults live in sprawling counties, there's a lower level of physical activity that they get as part of their daily lives," said the study's author, Reid Ewing, a researcher at the National Center for Smart Growth at the University of Maryland, College Park.

"They're driving to work, driving to lunch, driving to school, just about driving everywhere."


The study - to be published next month in the American Journal of Health Promotion - found that when differences in such factors as race, gender, consumption of fruits and vegetables, education and smoking are held constant, adults living in the most sprawling counties weigh 6 pounds more than those living in the most compact, densest jurisdictions.

"I know that when you talk about Smart Growth and sprawl, most people tend to focus on one of two things: either the environmental impact in terms of loss of open space, or the huge cost on the tax bill to subsidize sprawl," said former Gov. Parris N. Glendening, who is now president of the Smart Growth Leadership Institute.

"The most fundamental aspect is health. Sprawl is hazardous for your health. ... Unfortunately, with sprawl, we are designing obesity and high blood pressure and heart attacks and asthma right into our lives."

Of the 13 Maryland counties included in the study, Queen Anne's and Carroll counties were found to be the two in which sprawl creates the highest risk of obesity and hypertension.

Baltimore City was found to be the healthiest in terms of sprawl, followed by Montgomery, Prince George's, Anne Arundel and Baltimore counties.

"Something that comes up again and again in community planning is that there should be sidewalks," said Darlene Flaherty, a nutritionist with the Carroll County Health Department.

"When I see patients who are obese and tell them to walk more, they say there's nowhere to walk. They say there aren't sidewalks, or it's not safe to walk on the side of the road. It's a real problem."

Nevertheless, health officials in the counties identified for sprawl say they don't see the weight or hypertension problems being any greater than elsewhere in Maryland.


"The whole country is worried that obesity is a problem, and we're obviously worried about it here, too," said Dr. Chinnadurai Devadason, health officer for Queen Anne's. "But I think we're similar to other counties, that obesity is no worse here. Exercise and walking are quite a big deal."

Of course, sprawl alone doesn't overwhelm all other factors affecting health. For example, Baltimore City's denser neighborhoods are better for residents' health than those in Baltimore County, but the average city dweller still has a higher body mass index than those living in the county - likely the result of differences in race, education and income.

The study is the highlight of two peer-reviewed medical journals that are devoting their September issues to the health effects of community designs.

Another study set to appear in the American Journal of Public Health found that both pedestrians and bicyclists in the United States are far more likely to be killed or badly injured in auto accidents than the Germans or Dutch, in part because of the way streets and residential neighborhoods are designed.

"I've become increasingly convinced that we have not paid enough attention to how we build our homes, our offices and our neighborhoods, and how that affects our health," said Dr. Richard Jackson, a pediatrician and special adviser to the director of the Centers for Disease Control and Prevention.

"Many of the important decisions, like zoning, are made at a county or smaller level, and it is very important that those counties have someone paying attention to future building, to future design, and how that affects health."


More compact communities also can be popular if designed properly, said Dan Pontius, director of the Baltimore Regional Partnership.

"I think people intuitively know this is the kind of lifestyle they want, being able to walk to the corner store or the neighborhood school," Pontius said. "It makes life more pleasant. Now we know that it adds to your health as well."

To study the impact of sprawl on health, Ewing and his research team created a sprawl index to assess the 448 jurisdictions around metropolitan centers, covering about two-thirds of the U.S. population. Jurisdictions were judged on such factors as housing density and size of blocks.

While the most sprawling counties tended to be in the Southeast, the county with the most spread-out development was Geauga, outside of Cleveland, Ohio. Manhattan and New York City's other boroughs were the most densely populated areas in the study.

Ewing then turned to a CDC database of the health and behavior of more than 200,000 Americans. After adjusting for other factors that are known to affect health, he found statistically significant differences in people's weight, body mass index and rates of obesity and high blood pressure, depending on whether they live in dense or sprawling communities.

For example, he found that the effect on obesity and hypertension between living in the most compact and least compact counties was roughly equivalent to whether a person smokes, as well as about the same as whether a person eats more than three servings of fruits or vegetables a day.


But Ewing said some other factors had a greater impact than sprawl, including education, race and age.

"Sprawl is the dominant development pattern in the United States, and even those who would like to live in a walk-able place don't have many good options," Ewing said.

Maryland advocates of Smart Growth said they weren't surprised by the study's results and called on jurisdictions to focus more resources on mass transit and older neighborhood revitalization efforts.

Dru Schmidt-Perkins, executive director of 1000 Friends of Maryland, said that when she speaks to groups, she emphasizes the shift that has occurred in just one generation away from children walking to school each day.

"Just in getting kids to school, kids have lost out on that basic, 15-minute walk twice a day," she said. "You can see another cost of our growth patterns of the last 50 years."

Sprawl's effect on health


Development in 448 metropolitan jurisdictions was assessed for the amount of sprawl, with higher scores being assigned to denser areas. Researchers reviewed health records at the Centers for Disease Control and Prevention to evaluate what effect sprawling development had on expected weight (of average adults) and the risk of hypertension and obesity, holding all other factors equal. Here are the results of the 13 Maryland jurisdictions included in the study.

Sprawl Expected Difference in odds of:

County Score weight Hypertension Obesity

Anne Arundel 107.75 166.47 -0.92% -1.63%

Baltimore Co. 107.02 166.49 -0.83% -1.48%

Baltimore City 162.76 162.76 -7.20% -12.46%


Calvert 90.84 166.84 1.10% 1.96%

Carroll 81.92 167.04 2.17% 3.91%

Cecil 86.87 166.93 1.57% 2.82%

Charles 89.72 166.87 1.23% 2.20%

Frederick 87.09 166.93 1.55% 2.77%

Harford 92.47 166.81 0.90% 1.61%


Howard 93.65 166.78 0.76% 1.36%

Montgomery 112.70 166.36 -1.50% -2.66%

Pr. George's 112.42 166.37 -1.47% -2.60%

Queen Anne's 77.24 167.14 2.75% 4.94%

Source: Measuring the Health Effects of Sprawl, Smart Growth American, Surface Transportation Policy Project