Ironworker Jeff Devine tightens bolts on an I beam at his fiftieth floor worksite in Chicago. (From the book What I Eat: Around the World in 80 Diets.) The caloric value of his typical day's worth of food on a day in the month of September was 6,600 kcals. He is 39; 6'1" and 235 pounds. He carries a cooler of ready-to-eat food from home rather than eat at fastfood restaurants and vending trucks. At right: Jeff tightens the bolts on an I beam.