Scientific American Frontiers on PBS

Host Alan Alda gets the skinny on obesity in this episode. Included: a visit to the New England Deaconess Beth Israel Hospital's Nutrition Center, where staffers are prescribing moderation (500 fewer calories a day) and common-sense eating. At Penn State, nutritionists are studying why young children eat the way they do. And in Buffalo, a 9-year-old's eating and activity habits are closely monitored. One finding: as activity decreases (and TV-watching increases) food intake goes up. “It's a trap,” says Alda, “that will last for life.”