There a few methods that can be helpful in determining if your body weight is within a healthy range, including BMI measurements and measuring body fat & its location. Body mass index (BMI) is a calculation of weight in relationship to height and can be used to assess if weight increases health risks. It is not a direct measure of body fat and may be inaccurate for people who are muscular or who are frail due to illness.
Body fat can be measured by skinfold thickness measurements using calipers and bioelectrical impedance. More costly measures include dual-energy X-ray absorptiometry (DXA), underwater weighing, and air displacement using a Bod Pod. These techniques all can be used to measure the percentage of body fat. Individuals with central obesity, who carry excess fat around the middle, have an increased risk of several chronic diseases, regardless of BMI.