Well if you watch the Subway commercials where the compare their subs to McDonald's I'm pretty sure they use their 12" subs. I could be wrong. But, even if you do the 6" tuna on wheat, its at least as bad a infamous Big Mac - one of the poster children for fast food junk food.

The difference is when one orders a Big Mac they know they are about to eat junk, when one orders a tuna on wheat at subway they usually have no idea. And I don't have a problem with cheat meals, its when you think you're eating a healthy meal and are actually eating junk that problems start occuring.