A 68-year-old woman comes to your office for the first time. She has a BMI of 33 kg/m2. Her nutrition-focused physical exam is normal. To classify her as obese, what further information do you need? A. No further information; BMI is sufficient B. Waist circumference C. Additional anthropometrics D. DEXA scan
The correct answer and explanation is:
The correct answer is A. No further information; BMI is sufficient.
Obesity is classified based on body mass index (BMI), which is a standard and widely used method for assessing body fat based on height and weight. According to the World Health Organization (WHO), a BMI of 30 kg/m² or higher is classified as obese. In this case, the patient has a BMI of 33 kg/m², which falls within the obesity range.
Further measurements, such as waist circumference, additional anthropometric data, or DEXA scans, are useful for assessing the distribution of body fat or determining the specific health risks related to obesity but are not required to diagnose obesity. For example, waist circumference can indicate abdominal obesity, which is associated with a higher risk of cardiovascular disease and metabolic complications. However, for the purpose of classifying obesity, BMI alone is sufficient.
A DEXA (Dual-Energy X-ray Absorptiometry) scan provides a more detailed analysis of body composition, including the percentage of fat mass versus lean mass. While this is useful for more precise body composition analysis, it is not necessary for a simple obesity classification.
Anthropometric measurements like skinfold thickness or bioelectrical impedance analysis (BIA) can offer insights into body fat distribution but are not essential for diagnosing obesity.
In conclusion, the classification of obesity relies on BMI as the primary metric. Although additional information may be useful for understanding a patient’s overall health or risk factors, it is not required for determining whether a person is obese based on the standard criteria.