The authors studied 7,334 children between the ages of 3 and 18 residing in Marion County, Ind., and determined whether they were overweight by calculating their body mass index. They also looked at amounts of green landscapes and also proximity to food retail -- fast-food restaurants, convenience stores and supermarkets -- of each child's home using satellite imagery and geographic information.
The researchers did not evaluate the children's exercise behaviors, but reported that those who lived in higher population density regions with less greenery were more likely to have a BMI above the 85th percentile, putting them "at risk for overweight."
By comparing high population areas with low population areas, they found that as the difference between the areas' "vegetation index" increased, so did the odds of being overweight.
"I was intrigued by our results," said lead author Dr. Gilbert Liu, of the Indiana University School of Medicine.
Making the connection between green space and obesity can be tricky because many parks can be empty of children because of the fear of crime, according to Thomas Glass of the Johns Hopkins Bloomberg School of Public Health.
The findings are published in the March/April issue of the American Journal of Health Promotion.