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."
Spurlock Weighs In
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.
His doctors worried about him. One is quoted in the film telling the director to, "Stop doing what you're doing. You're pickling your liver."
Another doctor suggests he was addicted to the food, because his mood improved every time he ate. Spurlock said he would get headaches that went away the minute he started to eat the food.
After 30 days of the experiment, he says he gained 24½ pounds, his liver turned to fat and his cholesterol shot up 65 points.
But wait a second; is it really the fault of McDonald's? Do we blame Ford because cars lead us to avoid exercise? Do we blame ABC because TV invites us to be couch potatoes?
We spoke to some filmgoers who saw the movie and blamed McDonald's for Spurlock's weight gain.
One man told us the corporation is wrong for putting "stuff in their food that makes you want to eat it over and over again." A woman said advertising by McDonald's is influencing our habits.
And yet Spurlock told us he's not looking to place blame. "I don't point the finger at McDonald's and blame them for the obesity epidemic … McDonald's is iconic of the problem," said Spurlock.
Personal vs. Corporate Responsibility
In "Super Size Me," Spurlock asks where personal responsibility ends and corporate responsibility begins.
We can debate corporate responsibility, but the important point is that personal responsibility never ends. That's why "Super Size Me" is making some people mad.
We talked with two adults who have nothing to do with McDonald's Corp., but who think the documentary sends the wrong message.
"Making a film like this doesn't help anybody," said 49-year-old Soso Whaley. "It just allows people to say, 'It's McDonald's fault or it's fast food, or it's a hamburger. That's why I'm fat.' "
Whaley did her own 30-day test. The result? The New Hampshire resident lost 10 pounds and her cholesterol dropped 40 points from 237 to 197 during a month of fast food meals. She said after the diet her liver was healthy and "in general, I felt pretty darn good."
How did Whaley lose so much weight? She didn't pig out the way Spurlock did.
"I might have a McGriddle sandwich with bacon, egg and cheese and some orange juice. For lunch I might have a salad … dinner, well maybe I'd be in the mood for a Big N' Tasty," said Whaley.
She ate fewer than 2,000 calories a day.
California resident Chazz Weaver ate as much as Spurlock did, up to 5,000 calories a day. After 30 days Weaver lost eight pounds, going from 222 to 214 and his HDL cholesterol level improved by 80 percent.
The difference between Spurlock and Weaver was exercise. Weaver works out an hour and 15 minutes a day. "Could somebody eat McDonald's every single day and lose weight? Yes," said Weaver.
I told Spurlock about their weight loss. He pointed out that they ate less and exercised, which is something "no Americans do." I then told Spurlock I thought the film was rigged because he bought the fattiest foods.
What if you went to the finest French restaurant and took in 5,000 calories a day, wouldn't the same thing happen?
Spurlock replied: "I don't know. Maybe you should make that film."
Maybe I will. Give Me a Break.