Body composition and BMI differ in their approaches to measuring health. Body composition assesses the proportion of fat, muscle, and bone in the body, providing a clearer picture of overall fitness. In contrast, BMI (Body Mass Index) is a numerical value derived from height and weight, which may not accurately represent an individual's health status. While BMI can categorize weight categories (underweight, normal, overweight, obese), body composition offers deeper insights into the quality of an individual's weight and fitness level.