An article in the New York Times a few months ago summarised quite nicely recent research into connections between transport modes and health outcomes:
Millions of Americans like her pay dearly for their dependence on automobiles, losing hours a day that would be better spent exercising, socializing with family and friends, preparing home-cooked meals or simply getting enough sleep. The resulting costs to both physical and mental health are hardly trivial.
Suburban sprawl “has taken a huge toll on our health,” wrote Ms. Gallagher, an editor at Fortune magazine. “Research has been piling up that establishes a link between the spread of sprawl and the rise of obesity in our country. Researchers have also found that people get less exercise as the distances among where we live, work, shop and socialize increase.
Obviously there’s nothing really new in the fact that obesity creates significant health problems and that our car dependent lifestyles have created a culture where people have to go out of their way to exercise – and therefore many just don’t get around to it. What’s perhaps most interesting though is just how related obesity rates and other health problems appear to be with our urban form and our transport choices:
“In places where people walk more, obesity rates are much lower,” she noted. “New Yorkers, perhaps the ultimate walkers, weigh six or seven pounds less on average than suburban Americans.”
A recent study of 4,297 Texans compared their health with the distances they commuted to and from work.It showed that as these distances increased, physical activity and cardiovascular fitness dropped, and blood pressure, body weight, waist circumference and metabolic risks rose.
The report, published last year in The American Journal of Preventive Medicine by Christine M. Hoehner and colleagues from the Washington University School of Medicine in St. Louis and the Cooper Institute in Dallas, provided causal evidence for earlier findings that linked the time spent driving to an increased risk of cardiovascular death. The study examined the effects of a lengthy commute on health over the course of seven years. It revealed that driving more than 10 miles one way, to and from work, five days a week was associated with an increased risk of developing high blood sugar and high cholesterol. The researchers also linked long driving commutes to a greater risk of depression, anxiety and social isolation, all of which can impair the quality and length of life.
It’s not just in the US, similar results come from a Swedish study:
A Swedish study has confirmed the international reach of these effects. Erika Sandow, a social geographer at Umea University, found that people who commuted more than 30 miles a day were more likely to have high blood pressure, stress and heart disease. In a second study, Dr. Sandow found that women who lived more than 31 miles from work tended to die sooner than those who lived closer to their jobs. Regardless of how one gets to work, having a job far from home can undermine health. Another Swedish study, directed by Erik Hansson of Lund University, surveyed more than 21,000 people ages 18 to 65 and found that the longer they commuted by car, subway or bus, the more health complaints they had. Lengthy commutes were associated with greater degrees of exhaustion, stress, lack of sleep and days missed from work.
Fortunately it’s not all bad news though. The trends we’re seeing with fewer young people getting driver’s licenses than earlier generations, contributing to the general decline in per capita driving over the past 7 or so years offer some hope to researchers that perhaps we’re finally “turning a corner” on many of these trends:
In her book, Ms. Gallagher happily recounts some important countervailing trends: more young families are electing to live in cities; fewer 17-year-olds are getting driver’s licenses; people are driving fewer miles; and bike sharing is on the rise. More homes and communities are being planned or reconfigured to shorten commutes, reduce car dependence and facilitate positive interactions with other people.
Dr. Richard Jackson, the chair of environmental health sciences at the University of California, Los Angeles, says demographic shifts are fueling an interest in livable cities. Members of Generation Y tend to prefer mixed-use, walkable neighborhoods and short commutes, he said, and childless couples and baby boomers who no longer drive often favor urban settings.
While there is still a long way to go before the majority of Americans live in communities that foster good health, more urban planners are now doing health-impact assessments and working closely with architects, with the aim of designing healthier communities less dependent on motorized vehicles for transportation.