In general it's bad ... it has poisons colourans MSG and all sorts of yummy stuff. McDonalds and KFC probably being the worst.
Not being a dad as yet, the wife and I both try to stay away from any junk food, but comming home late from work when nobody wants to cook - pizza IS a lifesaver.
Feed them good things and try and discourage the bad. If you are a good cook and you can make wholesome food taste good then you have won half the battle.
i definitely dont permit my kids to eat fast food ! its junk! yes i do let them have it occasionally..everything should have its limits and theres no reason why they cant have once or twice in a week or so.
We do but only as a special treat. We don't stop al lthe time or even once a week. My sister-in-law on the other hand feeds her kids fast food 5 out of 7 days on average. Horrid, I know.