PARK CITY — For a month last year, Morgan Spurlock's eating ritual was what he called "every 8-year-old's dream." The filmmaker got to go to McDonald's for all of his meals, three squares a day, for 30 straight days — and he didn't have to plead with his parents or swear he'd clean his room later.

And not only did Spurlock feast at Mickey D's enough to be considered "Customer of the Month" — perhaps even "Customer of the Decade" — but he also brought a camera crew along for every single bite, bellyache and, well, barfing moment.

As you find out from watching "SUPER SIZE ME: A Film of Epic Portions" at the Sundance Film Festival, boy, did he ever need the detox diet his girlfriend (a devoted vegan chef) drew up for him at the end of his fast-food frenzy.

Warning: The witty filmmakers rated the movie "F" for "fat audiences," which includes most of America. Audiences should know that "some food may not be suitable for young children" (despite what all the cute, indoctrinating commercials from the food industry may claim).

Spurlock hopes the film and his eating experiment will serve as a wake-up call for Americans who — as he, nutritionists, doctors, even a former Surgeon General he consulted with believe — are eating themselves to death.

"If there's one thing we could accomplish with the film, is that we make people think about what they put in their mouth," Spurlock said. "So the next time you do go into a fast-food restaurant and they say, 'Hey, would you like to upsize that?' You think about it and say, 'Maybe I won't. Maybe I'll stick with the medium this time.' "

He painfully found out that inhaling an insane amount of Big Macs, Quarter Pounders, Chicken McNuggets, French fries, shakes, Filet o' Fish sandwiches, Egg McMuffins, hash browns, soda pop and so on, for 90 meals in a row, wreaks havoc on one's system. Then again, he points out, so does eating out as much as most Americans do.

That's why he decided to become the anti-Jared — the "Subway Diet" dude has a role in this documentary, by the way — and participate in a month of McDonald's madness. So, much to the chagrin of his loved ones and the health advisers , Spurlock limited his exercise and gulped down about 5,000 calories a day at McDonald's across the country. All told, he ingested about 30 pounds of sugar and 12 pounds of fat from the fast food.