Where you live may determine your child's weight, according to a series of new studies published this week.
In a special issue of the American Journal of Preventive Medicine, researchers from the U.S., Canada and the United Kingdom used geographic information systems (GIS) to look at how features of neighborhoods children live and play in affect their health.
What they found is that characteristics of the neighborhoods children live in could be contributing to the high rate of obesity in the U.S. and elsewhere.
In one study, researchers used geographic information to determine which neighborhoods in King County, Wash. and San Diego County, Calif. rated highest in terms of physical activity and nutrition for children ages 6 through 11. A neighborhood received a high rating if there were ample opportunities to walk to places, such as stores and libraries as well as highly-rated parks.
These neighborhoods also had numerous grocery stores or supermarkets where produce and healthy foods were available.
Neighborhoods that rated poorly had few markets available or had a large number of fast food restaurants and also did not offer many chances to walk or play in high-quality parks. There were also neighborhoods rated in between good and poor.
"The biggest difference we found in rates of obesity were in the places where the environment was good for both nutrition and physical activity, the rates were less than 8 percent, but if the nutrition and physical activity were not good, the rates went up to 16 percent," said Brian Saelens, a co-author and professor of pediatrics at Seattle Children's Research Institute.
Saelens added that researchers controlled for other variables that could contribute to obesity, such as income, family status and parental body mass index (BMI).
In an accompanying paper, Saelens and his colleagues used GIS data to define "obesogenic" environments as those that offer little in the way of physical activity and good nutrition. The authors say GIS measures should be used to assess the relationship between physical activity, nutrition and obesity.
By using GIS data, Saelens explained they were able to obtain objective, detailed information about how many parks, grocery stores and other places were in each of the neighborhoods.
Spatial technology, explained Stephen A. Matthews of Pennsylania State University, is rapidly becoming a valuable research tool.
"As GIS has matured (the ready availability of geospatial data, enhanced visualization tools, and advanced analysis methods), there has been an explosion of interest in the application and use of spatial concepts and methods in health-related research," Matthews wrote in commentary.
And in another commentary, Celeste Marie Torio of the Robert Wood Johnson Foundation wrote that while GIS-based research is still in its early stages, it may "help enhance our understanding of how the multitude of factors and their interactions influence childhood obesity, and help us reverse this epidemic."
GIS research still faces many challenges, wrote Janne Boone-Heinonen of the University of North Carolina at Chapel Hill and Penny Gordon-Larsen of Oregon Health and Sciences University, but it still holds a lot of promise for driving policies geared toward preventing and reducing childhood obesity.
In a study of adolescents from Halifax, Nova Scotia, researchers found that rural teens get most of their physical activity during school, while urban and suburban teens get most of their activity during their commutes to and from school.
Policies geared toward combatting childhood obesity should take the varied sources of physical activity into account, the authors argued.
"Policies developed to promote physical activity should sustain the walkability and active transport option in urban areas and, concurrently, improve and enhance options for youth outside of the urban core to engage in active commuting," they wrote.