(AP) CHICAGO Older American teenagers living in poverty have grown fatter at a higher rate than their peers, according to research that seems to underscore the unequal burden of obesity on the nation's poor. "Today the percentage of adolescents age 15-17 who are overweight is about 50 percent higher in poor as compared to non-poor families, a difference that has emerged recently," said Johns Hopkins' sociologist Richard Miech, the study's lead author. Obesity rates among all teens climbed substantially during the study, which covered 30 years. But the great divide according to income occurred most notably among the 15- to...