Why American fast food is unhealthy?

Subway, as a self-help sandwich bread, can be eaten healthily with proper collocation. There are 6 inches of whole wheat bread to choose from. Among the matched meats, turkey breast, roast beef and tuna are relatively healthy, plus appropriate amount of cheese and favorite vegetables. Finally, it is recommended to choose pepper or yellow mustard sauce as the sauce, so that you can get very adequate nutrition.