Some Philadelphia corner stores are encouraging customers to select healthier foods. The goal is to improve the health of poor people in neighborhoods where diet-related problems, including obesity, are rampant. In a study, researchers from Temple's Center for Obesity Research and Education found that urban children visit corner stores an average of once a day and purchase 350 additional calories. "The three most popular items were soda, chips and candy," said researcher Stephanie Vander Veur.