Brought up in Manhattan on home-cooked meals (the exceptions: The Good Earth Chinese restaurant on 72nd Street and Tip Toe Inn on 86th on alternate Sunday nights for dinner) I somehow never got to eat a Big Mac until I was 45, when my children dragged me to McDonald's as a special birthday treat. As expected, it was tasteless, but I finally understood the pull of fast food. I still like the occasional Egg McMuffin.

Now Morgan Spurlock, an NYU Film School graduate, no doubt looking for a winning expression of his talent, has found it in spades with "Super Size Me," a film that's both funny and scary at the same time. He decided on a 30-day experiment in which he would eat nothing but McDonald's - and to enhance the deal, if asked whether he'd like to 'Super-Size that,' he would have to say yes.

Before he started, he consulted three doctors, who measured him (6 feet 2 inches, 185 pounds), checked his body fat (11 percent), his cholesterol (146) and his general health (good). He would then have them check him every 10 days during the experiment. His girlfriend Alex, a vegan chef, had lots of misgivings and worried about what would happen. She was right to worry. By the end of the first ten days he had gained 9 pounds, his cholesterol had shot up more than 100 points, and even his liver was showing signs of trouble. By the 30th day he had gained 25 pounds and his liver looked like that of a terminal alcoholic. Alex even noted his loss of sexual function.

But the film is of course much more than the tedious repetition of McDonald's meals. Spurlock traveled across the country, checking with other McDiners (no one could tell him what a calorie is), with nutritionists, with the former Surgeon General of the United States, and - unsuccessfully - with the spokeswoman for McDonald's, who never managed to answer his questions about their nutritional policies. He visited schools and asked about their cafeteria meals (mostly very bad, with the exception of a Wisconsin high school for problem kids that switched providers to one that offered healthy foods, and found that their behavior and learning skills improved).