'Super Size Me' Carries Weight With Critics

June 18, 2004 -- -- Morgan Spurlock's movie, "Super Size Me" won the best director award at the Sundance Film Festival and is now racking up ticket sales unheard of for a low budget documentary.

Watch John Stossel's full report Friday on 20/20 at 10 p.m.

For the film, he eats fast food for 30 days to see what would happen to his health condition. The resulting documentary is earning high praise, and held a spot in the top 10 at the box office for three weeks.

"It's incredible … unbelievable," Spurlock told ABC News.

Soon after Sundance, McDonald's announced it would stop "super sizing" its offerings, meaning if customers want extra french fries they no longer have the option of upgrading to an extra-large size at a discounted price. They deny it had anything to do with the movie.

"Amazing coincidence, right?" said Spurlock.

When two obese girls sued McDonald's, it gave Spurlock the idea for the movie. The judge threw out the case saying the girls couldn't prove McDonald's made them fat, so Spurlock decided to do his own test.

He ate all of his meals at McDonald's for 30 days straight and filmed it for the documentary "Super Size Me." Whenever they offered to super size his order, he accepted.

Spurlock also cut back on his exercise routine, trying to match what most Americans do. And of course it soon had an effect.

As he said in the movie: "Now's the time of the meal when you start getting the McStomachache. You start getting the McTummy. You get the McGurgles in there. You get the McBrick."

On the McDiet, he was eating twice as much as he normally eats — an average of 5,000 calories every day — so no wonder he felt sick.

As the weeks passed, his health worsened. In the film he describes his condition, saying he had trouble breathing, became hot and felt like he was having heart palpitations.