There's a witty and disturbing satire by Stanislaw Lem called The Futurological Congress. It's one of those books where the hero gradually comes to understand that the world isn't as it seems. He's ended up in this future utopia, but there are some puzzling details that don't quite fit. For example, why do people often appear out of breath when they get out of the elevator?

In the end, all is revealed. He's sitting with a friend in a fancy restaurant, and (view spoiler)[the guy says that yes, much of their life is an illusion. This is well known, though people prefer not to talk about it. But if he's so curious, there's a thing he might want to try. It's a chemical that will strip off all the multiple illusions that are projected in order to make life look pleasanter than it really is.

So the hero hesitates a moment, and then he takes the red pill. (In this book, it's a preparation based on very intense smelling salts, a touch I liked). The real world appears. He suddenly sees why you're breathless when you get out of the elevator. There are no elevators: people are swarming up and down the grillwork of the shafts like climbing apes. His friend, who a moment ago looked like a healthy, successful, middle-aged scientist type, is revealed as a hideously deformed cripple. The cordon bleu meal in front of them turns out to be a ghastly pile of chemical slop. (hide spoiler)]

His friend looks at him in alarm.

"Was I... much changed?" he whispers.

Well, it's not quite as bad as that with Fast Food Nation, but, as Gulla says in the comment below, you won't want to eat a hamburger again. It will be much changed.