| Demographic Group: | Resident persons aged >=18 years. |
| Numerator: | Respondents aged >=18 years who have a body mass index (BMI) >=25.0 kg/m² calculated from self-reported weight and height. |
| Denominator: | Respondents aged >=18 years for whom BMI can be calculated from their self-reported weight and height (excluding unknowns or refusals to provide weight or height). |
| Measures of Frequency: | Annual prevalence — crude and age-adjusted (standardized by the direct method to the year 2000 standard U.S. population, distribution 9*) — with 95% confidence interval. |
| Time Period of Case Definition: | Current. |
| Background: | In 2002, a total of 37% of adults were overweight, and 22% were obese. The prevalence of overweight and obesity has been increasing in the United States. |
| Significance: | Physical inactivity and unhealthy eating contribute to obesity and a number of chronic diseases, including some cancers, cardiovascular disease, and diabetes. Being overweight or obese increases the risk for multiple chronic diseases, including heart disease, stroke, hypertension, type 2 diabetes, osteoarthritis, and certain cancers. An appropriate amount, intensity, and duration of regular physical activity and decreased caloric intake might reduce a person’s BMI. |
| Limitations of Indicator: | Respondents tend to overestimate their height and underestimate their weight, leading to underestimation of BMI and of the prevalence of overweight and obesity. Recently published guidelines have established additional BMI cut points for weight: Underweight, <18.5; Normal, 18.5–24.9; Overweight, 25.0–29.9; Obesity I, 30.0–34.9; Obesity II, 35.0–39.9; Obesity III, >=40.0. |
| Data Resources: | Behavioral Risk Factor Surveillance System (BRFSS).
http://apps.nccd.cdc.gov/brfss/ |
| Limitations of Data Resources: | As with all self-reported sample surveys, BRFSS data might be subject to systematic error resulting from noncoverage (e.g., lower telephone coverage among populations of low socioeconomic status), nonresponse (e.g., refusal to participate in the survey or to answer specific questions), or measurement (e.g., social desirability or recall bias). |
| Healthy People 2010 Objectives: | 19-1: Increase the proportion of adults who are at a healthy weight.
19-2: Reduce the proportion of adults who are obese. |
