Philadelphia's Deputy Mayor for Health and Opportunity Donald Schwarz says that Philly has the highest obesity rate of America's 10 largest cities. Almost a third of the city's adults are obese, and a whopping 57 percent of children in the city are obese or overweight. Obesity is often related to poverty, which also impacts many Philadelphians. "The economic drivers are that it's cheaper to eat a high-quantity, high-fat, good-tasting food that's convenient," said Gary Foster, director of Temple's Center for Obesity Research and Education. "In addition, you don't have access to a wide variety of foods."