Obesity is the percentage of the adult population estimated to be obese, defined as having a body mass index (BMI) of 30.0 or higher. BMI, as defined by CDC, is equal to weight in pounds divided by height in inches squared and then multiplied by 703. CDC has a calculator for BMI at www.cdc.gov/nccdphp/dnpa/bmi/calc-bmi.htm. The ranks are based on the preceding year’s data from CDC’s Behavioral Risk Factor Surveillance System (BRFSS). The BRFSS telephone survey has traditionally been completed by people using landlines. During the fielding of the 2011 BRFSS, the methodology was updated to include cellular telephones due to the large number of households that contain only cellular telephones and no landline telephones. Because of these changes, estimates of obesity prevalence from the 2012 Edition onward cannot be compared to estimates from previous years. Shifts in estimates from previous years may be the results of the new methods, rather than measurable changes in the percentages.

Obesity is one of the greatest health threats to the U.S. It contributes significantly to a variety of serious diseases, including heart disease, diabetes, stroke, and certain cancers as well as poor general health.[1] Obesity is a leading cause of preventable death in the U.S., causing an estimated 200,000 deaths annually.[2] The direct medical costs for treating obesity and obesity-related health problems are overwhelming. In 2008 it was estimated that $147 billion was spent on obesity or obesity-related health issues.[3] Obesity is more prevalent than smoking and is highly associated with chronic conditions and overall poor physical health similar to smoking and excessive alcohol consumption.[4] The causes of obesity are complex and include lifestyle, the social and physical environment, as well as genes and medical history. Poor diet and decreased physical activity are major lifestyle contributors to obesity. Since the 1980s, energy intake has steadily climbed and energy expenditure has declined, leading to a growing energy imbalance which closely mirrors the obesity rates.[5] There is growing evidence illustrating the importance of the environment in the obesity epidemic and the need for changes in the environment in order to better facilitate changes in lifestyle.[6] There have been successful interventions targeting a wide variety of populations with various strategies, from school based prevention programs to treatment interventions in aging adults.[7]-[8] While obesity is associated with an increased risk of developing numerous health conditions, weight loss is associated with an attenuation of those risks.[9] The CDC has put together a list of useful resources for community level interventions aimed at lowering obesity rates, available at www.cdc.gov/obesity/strategies/communityStrategies.html.