Understanding BMI and How It's Used

There are many ways in which a healthcare professional can assess a patient’s health. He or she might evaluate that person’s blood pressure, cholesterol levels, and personal medical history, for example. Body mass index (BMI) is another important approach to evaluating health, particularly for those who are concerned about their nutrition and are considering enrolling in a medical weight lossprogram.

Definition

Your BMI is a general measure of your estimated body fat, which is based on your height and weight. It’s a quick and easy screening tool that requires no medical tests to determine. Knowing your BMI will help you determine if you’re within a healthy weight range for your height. If you’re overweight or obese, the body mass index can also help you figure out how much weight you need to lose to be within a healthy range.

Interpretation

For adults, a BMI of 30 or higher indicates obesity. If your BMI lands between 25 and 29.9, you’re considered overweight. A number between 18.5 and 24.9 indicates a healthy, normal weight. If you are underweight, your number will be below 18.5.

Application

Your BMI is a screening tool that can help you determine if you need to enroll in a weight loss program. Since individuals who are overweight or obese are at a higher risk of health problems, such as high blood pressure, high cholesterol levels, diabetes, and certain cancers, the BMI provides a preliminary indicator of risk for these conditions. However, it’s important to note that the BMI isn’t a diagnostic tool; medical testing is needed to determine your true risk of health conditions. Furthermore, your BMI is only an estimate of your body fat; more accurate measurement tools include skinfold testing and underwater weighing.