Two-thirds of U.S. workers are either overweight or obese

Actually, the number might be even higher because respondents to the Gallup survey were self-reporting, and as we all know people have a tendency to underestimate their weight. From Real Time Economics:

Gallup estimates that 450 million days of work a year are missed because of weight and other health problems, resulting in an estimated cost of $153 billion in lost productivity. "The $153 billion in lost productivity estimated in this analysis would increase if it included presenteeism, which is when employees go to work but are less productive in their jobs because of poor health or wellbeing. Including part-time employees would also add to the estimate of costs in lost productivity," said Dan Witters and Sangeeta Agrawal who presented the data on Gallup's Web site. They also point to a study that puts the figure much higher at $1.1 trillion.