A list of the fattest cities in America ranks Kansas City 17th in the country. Men’s Fitness had ranked the city number two in the nation in 1999 … and number seven last year. While Kansas City people apparently are slimming down, at least as the magazine sees them, residents of St. Louis are getting porkier. The magazine rates St. Louis as the nation’s ninth fattest city. Two years ago, St. Louis was 19th. The magazine bases its ratings on sixteen factors.