Purpose: The purpose of this paper is to assess the economic costs of inactivity (including those attributable to obesity). These costs represent one summary of the public health impact of increasingly sedentary populations in countries with established market economies. Components of the costs of illness include direct costs resulting from treatment of morbidity and indirect costs caused by lost productivity (work days lost) and forgone earnings caused by premature mortality.
Methods: We searched the Medline database for studies reporting the economic costs of obesity or inactivity, or cost of illness. From the identified references those relating to obesity or conditions attributable to obesity were reviewed. Chronic conditions related to inactivity include coronary heart disease (CHD), hypertension, Type II diabetes, colon cancer, depression and anxiety, osteoporotic hip fractures, and also obesity. Increasing adiposity, or obesity, is itself a direct cause of Type II diabetes, hypertension, CHD, gallbladder disease, osteoarthritis and cancer of the breast, colon, and endometrium. The most up-to-date estimates were extracted. To estimate the proportion of disease that could be prevented by eliminating inactivity or obesity we calculated the population-attributable risk percent. Prevalence based cost of illness for the U.S. is in 1995 dollars.
Results: The direct costs of lack of physical activity, defined conservatively as absence of leisure-time physical activity, are approximately 24 billion dollars or 2.4% of the U.S. health care expenditures. Direct costs for obesity defined as body mass index greater than 30, in 1995 dollars, total 70 billion dollars. These costs are independent of those resulting from lack of activity.
Conclusion: Overall, the direct costs of inactivity and obesity account for some 9.4% of the national health care expenditures in the United States. Inactivity, with its wide range of health consequences, represents a major avoidable contribution to the costs of illness in the United States and other countries with modern lifestyles that have replaced physical labor with sedentary occupations and motorized transportation.