I ask a young 200 - kilo patient what he snacks on. ''Nothing,'' he says. I look him in the eye. Nothing? He nods. I ask him about his chronic skin infections, his diabetes. He tears up: ''I eat hot chips and fried dim sims and drink three bottles of Coke every afternoon. The truth is I'm addicted to eating. I'm addicted.'' He punches his thigh. In Fat City, Karen Hitchcock unpicks the idea of obesity as a disease. In a riveting blend of story and analysis, she explores chemistry, psychology and the impulse to excess to explain the West's growing obesity epidemic.