Workers who are overweight or obese miss more days of work than healthy employees – resulting in more than $153 billion in lost productivity annually, according to a new Gallup report.

The Gallup-Healthways Well-Being Index found workers with above-normal weight and have one to two chronic health conditions miss more days of work than those that are healthy with no chronic conditions.

Full-time employees of normal weight with no chronic conditions make up 13.9 percent of the work force and tend to take off 4 days of work per year. Those who are overweight or obese with no additional chronic condition have a slightly higher rate.

Workers with above-normal weight with three or more chronic conditions miss about 42 days per year.

Missing days of work also means lost revenue totaling $153 billion annually, four times the cost found in the United Kingdom the report found. The striking difference is due to fewer unhealthy workers in the U.K.

Study findings are based on telephone poll data collected from 109,875 full-time employees between Jan. 2 and Oct. 2.Respondents’ self-reported heights and weights calculated body mass index scores. Respondents’ also self-reported chronic illnesses including obesity; having ever been diagnosed with heart attack, high blood pressure, diabetes, high cholesterol, asthma, depression, or cancer; and recurring physical pain in the neck, back, knee or leg.

The study did not give specific reasons why overweight or obese employees were chronically absent, but 2005 National Institute of Health report on obesity and absenteeism found illness, injury and medical visits are behind employees missing work.