Study co-author Susan Babey, a senior research scientist at the University of California, Los Angeles, says nearly three-quarters of California teenagers live or go to school in neighborhoods that are crowded with fast-food restaurants, convenience stores, liquor stores, dollar stores and pharmacies, relative to the number of healthier food outlets, such as grocery stores, produce vendors and farmers markets.
Unsurprisingly, teens who live or go to school in such neighborhoods are more likely to drink soda and eat fast-food, Babey says.
"You are what you eat. You are, also, where you live," Babey says in a statement. "And if you live in a place where there's a fast-food restaurant or convenience store on every block, with few healthier alternatives, you are likely to eat more junk."
Using the 2007 California Health Interview Survey and InfoUSA, a 2007 database of U.S. businesses, the study's authors calculated a Home and School Retail Food Environment Index, which measured the number of less healthy food outlets relative to the number of healthier outlets.
The study found teens in more unhealthy neighborhoods were 17 percent more likely to drink soda every day and 18 percent more likely to eat fast-food at least twice a week than their peers in healthier neighborhoods.