Japan has the lowest obesity rate in the industrialized world, and yet, from schoolgirls to businessmen, it is a country where almost everyone seems to be on a diet. Why is weight loss such big business when so few people are overweight? This time on Japanology Plus, we look at Japan's weight loss industry. Our guest is Kiyoka Wada, an expert on dieting and fitness. And in Plus One, slimming down with a personal trainer.