Just now, looking around the office here in Tokyo - most of the engineers here sit at their screens day in day out from 9.30am through to past 10pm. Most of them don't exercise more than walking to the elevator and maybe standing on the train for the half hour daily commute. They are all, with a couple of exceptions, "skinny" by western standards. Why are these sedentary office workers not gaining the pounds? It's got to be the diet.