Morgan Spurlock gained a ton of weight in "Supersize Me," which did nothing for the chain's rep, but a high school science teacher in the Colo-Nesco School District in Colo, Iowa, has lost weight eating just McD's. He says he lost 37 pounds in 90 days, albeit by limiting his intake to 2,000 calories a day and eating the right balance. Jo Ann Hattner, a nutritional consultant at Stanford University School of Medicine said McDonald's has much improved its menu. "You have to give them some credit," she says.