I had a double cheeseburger from McD's today. It was the first time in 5 weeks and I got a headache. 5 weeks ago I got an anus burger and it made my stomache hurt like hell and prior to that I hadnt eaten McD's (or any other fast food) since beginning of July.
I definitely ate fast food more often in college and in my early twenties. Now I literally go to Wendy's maybe once every few months, and usually out of desperation because I don't have time and I'm in a rush. It's usually those times where I am on the road, and I am starving so I just have to stop. So I would say I only eat true fast food a couple of times a year.
I think it's fine in moderation. More than a couple times a month might be too much. Even once a week would be too much for me. I have a very weak stomach and I cannot handle grease.
But do you honestly think fast food is THAT bad for you?
To answer the OPs question, yes, fast food IS that bad for you. You can't live on that food. No nutritional value and the lowest grade meat possible. There is also bone in that meat. (it gets grinded in during the meat grinding process) That's disgusting.
Oh, and if I do eat fast food like Wendy's, I NEVER feel good after I eat it. While I'm eating it, it is satisfying my hunger and I am enjoying it in the moment, but after that I just feel like a walking pile of fat. You crash pretty fast after eating that type of food. Not good.
I started writing down what I was spending money on each month.....and let me tell you, THAT was a wake up call.
Now, I've pretty much cut out the McDonalds/Burger King/Taco Bell, but I do indulge in Jimmy Johns subs and Subway usually once or twice a week.