While discussing how McDonalds' suppliers raise their cattle, Spurlock writes in Don't Eat This Book:
"Leftover bits and pieces [of dead cows] are scooped up, ground together and fed back to the cows. And then those cows are ground up and fed to you." (p. 102)Actually, this process is called "ruminant feeding," and it has been banned by the FDA since 1997. Spurlock is accusing McDonalds of breaking federal law, and of continuing to break federal law for eight years.
This is a serious accusation, and one for which Spurlock provides no source. Either Spurlock or Putnam, his publisher, should provide an explanation as to how and why this accusation made it into the book.