It all comes down to what you get.
If you walk in and get one of their mini pizzas, or meatball sub with extra cheese, or etc., then no. But they have those under 5g's subs, AND some subways have the veggie pattie! Which is what i get allllll the time.......since i'm a vegetarian! And i KNOW the veggie patties are good for you.....but bread always isn't, so if you want to go there frequently, TRY TO SOMETIMES GET WHEAT BREAD.......don't get that yummy italian herbs and cheese bread ALL the time......AND, watch what you put on it.....and you should be good!
ESPECIALLY if you compare it to pizza hut, dominos or quiznos. Subway is a MUCH more healthy fast-food restaurant!! I live literally RIGHT beside one.....haha.