What does BMI provide a reliable measurement of?

BMI, or Body Mass Index, provides a reliable measurement of body fat based on a person's weight in relation to their height. It is calculated using a simple formula that applies to most adults, making it a widely-used tool in both clinical and public health settings. BMI categorizes individuals into different weight classes, such as underweight, normal weight, overweight, and obesity, which can help assess the risk for various health conditions associated with excess body fat, such as heart disease, diabetes, and certain cancers.

While BMI is a useful indicator of body fat for most people, it's important to note its limitations. It does not directly measure muscle mass or bone density, which means individuals with higher muscle mass, such as athletes, may have a high BMI that does not reflect their body fat percentage accurately. Additionally, BMI alone does not provide a complete picture of an individual's overall health, as it does not take into account factors such as age, sex, and distribution of fat throughout the body.