Last week I was meeting with a group at a fast food place. I had one of their salads with my own dressing, and one of their burgers, sans buns. I have to say, it was tasty, and I suffered no ill-effects. I wouldn't search them out, but if you are going to eat at a fast food place, there are semi-primal options to be had. I would definitely eat a McDouble, just without the buns.
Or the "cheese".
I believe their cheese really is cheese, not 'cheese food', although with 'American cheese' you get the extra 'stuff'. Still, not the WORST thing.
What's really in a McDonald's hamburger?
From that link, if you don't mind CAFO beef, the burger patty is the most benign thing on the ingredient list of a burger at McD.
I'd go with a can of tuna or sardines any day. IF would be even better.
"Right is right, even if no one is doing it; wrong is wrong, even if everyone is doing it." - St. Augustine