And the fattest city is...

Fast food restaurants -- Houston has twice the national per capita average -- are partly to blame for the dishonor, Men's Fitness editor-in-chief Neal Boulton said.

"Americans ... work long hours, don't take vacations, and when you're faced with the worst nutritional choices, you indulge in those," he said.

High humidity, poor air quality and some of the nation's longest commute times also helped Texas' most populous city unseat Detroit, the 2004 heavyweight champion, the magazine said.