What does Body Mass Index (BMI) measure?

Body Mass Index (BMI) is a widely used tool that quantifies body weight in relation to an individual's height. The calculation of BMI is straightforward: it involves dividing a person's weight in kilograms by their height in meters squared (kg/m²). This ratio provides a numerical value that can be categorized to help assess whether a person is underweight, at a healthy weight, overweight, or obese.

BMI is particularly valuable because it allows for a general assessment of body weight status across different populations without the need for complex measurements of body fat or composition. However, it is important to note that while BMI can indicate potential health risks associated with weight, it does not measure body fat directly. Therefore, individuals with the same BMI may vary significantly in actual body fat percentage due to factors like muscle mass, bone density, and distribution of fat in the body.

In contrast, options regarding the direct measurement of body fat, bone density, or muscle strength pertain to different assessments or methodologies that evaluate specific body composition factors rather than providing a general overview based solely on height and weight.