And he got sick on his first day. The guy is either a major wuss bag of massive proportions (probably his wife's vegetarian influence) or he forced himself to be sick.
I really wouldn't doubt it was from the diet change. I'm no vegetarian (quite the opposite actually) and even though I know I shouldn't sometimes I do get the craving for a Micky D's Burger... My stomach tells me off afterward. -.-
Then from there, it's just like anything bad for you and addicting: You become immune to it, getting sick from it less, etc.
I actually had to watch this movie in my Food Science Class during my Senior Year of High School. It was interesting... to say the very least.
I have quite the phobia of vomiting, so sitting in front of everyone trying to cover my ears and close my eyes was difficult to pull off.
Once we got past that hurdle it was actually very interesting, if not disturbing, to watch. D= I remember somewhere they actually had delivery McDonald's, just absolutely crazy stuff.Towards the end it was kinda worrying, especially seeing the health decline from when he had started to when he stopped.
If anything good has come from this movie, and the demand from everyday consumers is that McDonald's and other fast food companies have at least given it a honest effort to "Clean up" the food they offer.