National Association of Nutritional Professionals (NANP) Domain IV Practice Test

BMI is the standard way to assess overweight and obesity in adults. It’s calculated by dividing a person’s weight in kilograms by the square of their height in meters. This simple ratio provides a consistent method to categorize weight status—such as underweight, normal, overweight, and obesity—and to monitor changes over time. It’s favored in clinical and public health settings because it’s quick, inexpensive, and requires only height and weight. While it doesn’t measure body fat directly or indicate fat distribution, it correlates with overall adiposity for most people and is effective for population screening and guiding further evaluation. Other measures like blood pressure, cholesterol, or body fat percentage inform cardiovascular risk or body composition but aren’t used to define overweight or obesity in adults the way BMI is.