The fourth largest U.S. city of Houston has been ranked by a leading health magazine as the nation\'s fattest city, with 34 percent of its population being overweight, according to U.S. media on Tuesday. Part of the reasons why the city becomes the country\'s fattest are the summer heat and long commutes to work, which keep people in the city on their bums, according to an ABC report. Houston also is ranked number one for fast food by Men\'s Fitness Magazine, with more than 1,000 fast food joints across the city to choose from, the report said. Three other Texas cities were also on the list, with El Paso ranked 7th, Arlington 15th, and Dallas 25th. Detroit, Cleveland, Memphis, and Tampa were the other cities making the top five.