Just 1 in 7 U.S. workers is of normal weight without a chronic health problem, according to Gallup polling data, and it could be costing the economy more than $153 billion a year in lost productivity from increased sick days.

Gallup polled more than 100,000 full-time workers, and found that two-thirds of the work force is either overweight or obese and nearly half are both overweight and have at least one chronic health problem. The numbers on obesity are calculated using self-reported height and weight, which means the numbers could be even higher. Studies have shown that people tend to underestimate their weight and overestimate their height.

Workers who were overweight or obese were more likely to miss work than those of normal weight, but chronic health problems were a much bigger factor. Even among those of normal weight, chronic conditions are prevalent, as nearly 60% of those workers report a continuing health issue. Chronic health problems included having ever been diagnosed with a heart attack, high blood pressure, high cholesterol, cancer, diabetes, asthma, or depression; and recurring physical pain in the neck or back or knee or leg in the last 12 months.

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.