If fast-food jingles were multiplication tables, perhaps we'd all be good at math. In the meantime, those ads sure are stuck in the brains of kids. The marketing of ultra-processed food, which accounts for more than 60 percent of calories for children, has coincided with a dramatic increase in childhood obesity across the United States. In 1970, about 1 in 20 children were affected by obesity; today, it's 1 in 5, according to the Centers for Disease Control and Prevention . To be clear, there