If you care about your kids eating healthy, getting enough exercise and avoiding obesity, pay close attention to where you live.
A special issue of the American Journal of Preventive Medicine released Tuesday contains six studies that rely on geographic mapping data to show how location impacts health.
Two of the studies focused on neighborhood attributes to determine how different features — the availability of parks and quality supermarkets, for example — affect obesity. They found a significant effect: kids who could walk to schools and libraries and find healthy food at nearby supermarkets were 59% less likely to be obese than kids whose neighborhoods didn’t allow that.
“We need to think about neighborhoods where kids live in terms of nutrition environments and in terms of physical activity environments, and we need to improve them,” says Brian Saelens, lead author of one of the neighborhood attribute studies and a professor of pediatrics and investigator at Seattle Children’s Research Institute at the University of Washington.
All six studies used computerized geographic information systems (GIS), which manipulate geospatial data to reflect visual representations of the real world. One study finds that urban and suburban children get the greatest proportion of their daily physical activity on the way to and from school — walking, for example, or biking. Rural kids, on the other hand, who likely face a longer commute to school via school bus or car, are most active at school. Another study analyzed the effect of the availability of fast food on teens, finding that adolescents in rural areas chose fast food more when such restaurants were close by. Accessibility was not as much of a draw for their counterparts in cities, who ostensibly have more choices.
GIS is a still-developing application, but the Robert Wood Johnson Foundation notes it has potential to help researchers make sense of the way physical environment affects health. The technique helped shine a light on the interplay between obesity rates and neighborhood characteristics in Saelens’ study. In King County, Wash. — where Seattle is located — and San Diego County, Calif., researchers selected particular neighborhoods that differed on important environmental factors. In some neighborhoods, residents could walk from their homes to libraries, schools, restaurants and parks; in others, that wasn’t an option. They also looked at access to supermarkets and fast food outlets.
They contacted families with kids between the ages of 6 to 12 in the neighborhoods and measured the height and weight of the children and one parent, usually the mother. They also collected demographic information such as income, age, education, which are known to affect obesity rates. Still, after accounting for the various demographic variables and controlling for parental BMI — also known to impact a child’s likelihood of obesity — they found that children who lived in neighborhoods that ranked high in both physical activity and nutritional “environments” had half the obesity rate of kids in neighborhoods that scored low in both areas. Those kids without easy access to parks, schools or healthy food had a 16% rate of obesity and their parents had a rate of 28% compared to 8% for children and 20% for parents who lived nearby supermarkets and could walk back and forth to school. General obesity rates for children hover at 18%; for adults, the estimate is one in three.
Saelens was part of a team that worked on recommendations for obesity prevention from the U.S. Centers for Disease Control and Prevention. The guidelines include increasing access to nutritious food in communities, particularly in low-income neighborhoods. Focusing more on preventing obesity requires some changes that could include taxing soda and other junk food and subsidizing healthier choices. It’s an uphill battle, acknowledges Saelens. “But the alternative is we continue to assume individuals are responsible for the eating and activity choices they are making,” he says. “There is some individual responsibility, but if we put someone in an environment where there are not very many good choices, we shouldn’t expect them to make better choices.”
The research could also be a commentary on America’s penchant for suburban living. “In the U.S. we struggle with density,” says Saelens. “We want to be able to walk to places, but we also want a big backyard. We are potentially compromising the health of our kids in doing that.”