What does BMI measure?

BMI, or Body Mass Index, specifically measures body weight relative to height. It is a calculation that uses an individual's weight in kilograms divided by the square of their height in meters. This method helps to categorize individuals into various weight status categories, such as underweight, normal weight, overweight, and obesity, which can provide insights into potential health risks associated with different levels of body weight.

While BMI does correlate with body fat levels in many populations, it does not directly measure body fat percentage; instead, it provides a basic estimate based on the weight and height provided. It is also important to note that BMI does not account for muscle mass, which can skew the interpretation of weight status among individuals with higher muscle mass, such as athletes. Similarly, it does not provide information about bone density. Therefore, while BMI is a useful screening tool, it is not a comprehensive measure of body composition or health status.