Perceptions of Body Mass Index as a Valid Indicator of Weight Status among Adults in the United States

Abstract

Background: Being overweight or obese increases risk for heart disease, stroke, type 2 diabetes, joint disease, and certain cancers. The Body Mass Index (BMI) is commonly used to determine weight status. As rates of overweight and obesity have risen sharply in the United States over the past 30 years, perceptions of a "normal" or healthy weight are subject to change. The purpose of this study was to analyze perceptions of BMI as an indicator of weight status. Methods: An online survey was administered to 376 US adults. The survey collected demographic information including height, weight, and perceived weight status (underweight, healthy weight, overweight and obese). The survey software calculated and presented participants with their personal BMI values. Participants then answered questions about their perception of the BMI as a valid indicator of weight status. Results: More participants reported a healthy weight status (51.6%) than were classified as such according to their computed BMI (43.6%). The majority of the sample (85.1%) considered BMI to be a valid indicator of weight status, although perceptions of validity varied by weight status. Participants that perceived BMI to be invalid most commonly cited incongruence with one's perception of their own body weight, no accounting for unique body shapes, and no accounting for additional muscle mass. Conclusion: BMI is generally perceived to be a valid indicator of weight status. These perceptions of validity can vary depending on the individuals' actual weight status. In instances where perceptions are not favorable toward BMI, it is largely attributable to opinions of incongruence with BMI and body shape, type, or composition. Continued use of BMI as a preliminary tool for determining weight status appears to be accepted. Efforts to increase BMI-related awareness and education may be necessary for individuals that currently see it as invalid.

Views of Own Body Weight and the Perceived Risks of Developing Obesity and NCDs in South African Adults

“…These findings are in line with what has been reported in a previous South African study [22]. Similarly, in a study conducted in the U.S., those who were overweight and obese underestimated their body weight [23]. The misperception of body weight status observed among the respondents in the study was associated with their BMI by a factor of 0.94 (95% CI (0.91-0.98), p < 0.05).…”