Seattle Times  [Printer-friendly version]
January 24, 2006


[Rachel's introduction: The basic orientation of public health is
called "primary prevention." That's the precautionary approach in a
nutshell -- look ahead and do your best to prevent problems before
they occur, rather than trying to manage them afterward. New studies
show that land-use decisions are making many of us sick. Therefore,
precautionary action is needed to prevent unhealthy land-use

By Eric Pryne

Residents of King County's less-walkable neighborhoods -- can you say
sprawl? -- are more likely to be overweight, a recently completed
study concludes.

Another related study has found, perhaps not surprisingly, that people
who live and work in those neighborhoods generate more auto-related
air pollution, another potential threat to health.

The two studies' findings are summarized in the winter edition of the
peer-reviewed Journal of the American Planning Association. The
authors, who collaborated in their research, say their work
constitutes the most comprehensive look yet at the link between urban-
development patterns and human health in a single metropolitan area.

Earlier research has raised the possibility of a connection between
sprawl, obesity and other health problems. The King County results
suggest "current laws and regulations are producing negative health
outcomes," the authors warn.

"None of this is saying suburbia is bad," said Lawrence Frank, an
urban-planning professor at the University of British Columbia and co-
author of both studies. "It just says these are the relationships you
get... and they should be taken into account."

A top aide to King County Executive Ron Sims said the county already
has adopted some changes as a result of the studies and is planning

The research isn't likely to end the debate over sprawl and health.

To learn more

Lawrence Frank of the University of British Columbia will speak about
his research on neighborhood design and health at 7 tonight at Town
Hall, Eighth Avenue and Seneca Street, Seattle. Admission is $10 with
advance registration, $15 at the door. For tickets and more
information, see

"If you're listing things that impact obesity, neighborhood design
would be maybe 10th on my list," said Tim Attebury, King County
manager for the Master Builders Association of King and Snohomish
Counties. "I would put McDonald's and too much TV way in front of
neighborhood design."

But Frank and co-author James Sallis, a health psychologist at San
Diego State University, said the two new studies go beyond previous
work in showing that development patterns can have a significant
impact on health even when taking into account other variables such as
age, income, education and ethnicity.

The walkability factor

For both studies, researchers ranked neighborhoods using a
"walkability index" that included such factors as residential density,
the number of street connections, and the mix of homes, stores, parks
and schools. All are believed to influence how much people walk.

In one study, funded by the National Institutes of Health, researchers
surveyed and monitored about 75 adults in each of 16 King County
neighborhoods. Eight neighborhoods, including Upper Queen Anne and
White Center, scored high on the walkability index; the other eight,
including Kent's East Hill and part of Sammamish, scored low.

Each group of eight included four wealthier and four lower-income

On average, researchers found, the Body Mass Index -- a measure of
height and weight -- of residents of the more walkable neighborhoods
was lower, and they were more likely to get the U.S. Surgeon General's
recommended 30 minutes of daily exercise.

In the second study, funded by the Federal Transit Administration,
King County and other local governments, researchers estimated the
auto-related pollution generated by about 6,000 King County residents
who kept detailed records of their travel for two days in 1999 as part
of another study.

Again, people who lived and worked in more walkable neighborhoods
produced fewer pollutants associated with smog, the study found.

Surprising finding

After subjecting the data to statistical analysis, Frank said,
researchers were surprised to learn that even small changes in
neighborhood design can make a difference.

A 5 percent increase in a neighborhood's walkability index, for
instance, was associated with a 0.23-point drop in Body Mass Index.
For someone 6 feet tall, that's a difference of less than 2 pounds,
but Frank said bigger changes in a neighborhood's walkability would be
expected to produce greater differences in weight.

The presence or absence of stores, parks, schools and other
destinations within a quarter- to a half-mile of home appears to be
the most important factor in how much people walk, he said.

Karen Wolf, a senior policy analyst in Sims' office, said that as a
result of the studies, the county already has amended the policies
that guide its planning to make health a priority.

County officials also are working on a checklist to rate development
projects' impact on health, she said.

In White Center, one of three neighborhoods that Frank and other
researchers studied in detail, Wolf said the county has rezoned
property to encourage "mixed-use" development that allows both housing
and shops, and is seeking a grant to develop an inviting walkway
between a redeveloped housing project and the community's business

"The whole idea is to make walking something you don't even think
about," she said. "It's part of your everyday life."

Eric Pryne: 206-464-2231 or

Copyright 2006 The Seattle Times Company