In another study, British researchers took a look at the relationship between obesity and the consumption of fast food by using GIS data to assess how many fast food restaurants were within about a half-mile of the homes of 13-year-olds.
A higher body mass index (BMI) and more body fat were both associated with eating fast food.
Food choices, availability of recreation areas and other neighborhood features also played a role in obesity among adolescents in the Minneapolis/St. Paul, Minn. area.
A low percentage of recreation areas, as well as the perception that neighborhoods aren't safe, were linked to higher BMI scores in boys and girls. Other intermingling factors associated with obesity were low socioeconomic status, a high number of convenience stores and fast food restaurants, and a lot of mass transit.
Experts not involved in this research say neighborhoods' detrimental effects on health have long been suspected, but there has been little solid evidence to back up the claims. These studies, they say, provide important data.
"We can confirm things that logically seem to be true, but we didn't have extremely strong data," said Dr. Richard Jackson, professor and chairman of environmental health sciences at the UCLA Fielding School of Public Health. "The evidence base is only now becoming very robust." Jackson is also the author of several books on the topic.
City and town planning policies have moved toward promoting healthier lifestyles in the past decade or so.
California and some other states have laws in place requiring that new roads must be constructed with everyone in mind, meaning drivers, pedestrians, bicyclists and people with disabilities, Jackson said.
"There's been a huge shift in the public health community's awareness of the built environment and its impact," he said.
But others say while the environment does pose barriers to healthier lifestyles for children and adolescents, parents still must take measures to overcome them by making different choices.
"In New York City, for example, there are parks all over the place, but people decide they don't want to take their kids to the park," said Keith Ayoob, associate professor of pediatrics at the Albert Einstein College of Medicine in the Bronx, N.Y. "There are things that make healthy behaviors difficult, but that's true whether people are rich or poor, and they're not insurmountable. People have to pay more attention to it, and parents have to set limits on what kids eat or what activities they engage in."