If you want a McDonald's sandwich with a meat other than beef, you're probably getting one of these two staples. But how do they stack up nutritionally?

These fast-food chains serve fish sandwiches made with real cod, pollock, or flounder—not processed fish patties.

Cold batter is key to a crispy fish fillet. Use ice-cold beer, and keep the batter chilled if you have to wait for the oil to come to temperature.