The presence of stores that sell junk foods close to schools does not necessarily impact kids' body mass index (BMI, a ratio of weight to height), according to a new study out of Maine.
Researchers writing in the Journal of Nutrition Education and Behavior mailed questionnaires to students at 11 area high schools asking about their height, weight and the amount of "calorie-dense" -- i.e. junk food -- they ate.
"The hypothesis," the researchers wrote, "was that students at schools with calorie-dense food choices nearby would be at greater risk for [being] overweight."
But that wasn't the case.
Of the 552 students surveyed, two-thirds said they consumed fast food monthly and half said they have soda at least once a week. (A recent Centers for Disease Control study showed that one in four high-schoolers drink soda daily.) But when the researchers crossed that data with how many establishments within driving distance sold "bad" food, they found that neither the proximity nor the number of stores predicted the odds of being overweight or obese.
There are, however, limitations to the study.
As Michael Goran, director of the Childhood Obesity Research Center at the University of Southern California told NPR, the population was small and the Maine environment is unique. Though 10 of the schools had at least one store nearby that sold soda and nine had at least one fast-food restaurant, Maine is a relatively rural setting. "I don't put very much weight behind this study," Goran told NPR.
Indeed, the authors themselves acknowledge that a recent study of 3 million ninth-grade students at more than 8,000 California schools did find a relationship between the existence of nearby stores and unhealthy food choices.
Still, they said the findings could have implications for better addressing the youth obesity epidemic, at least in non-urban environments like Maine. By focusing more on "student behavior" rather than what the researchers refer to as the "build environment near the school," nutrition programs might be more effective at reaching kids.