Is There an Alternative to BMI?

Most of our patients are familiar with Body Mass Index (BMI). It is the most commonly used measurement of body size, but it is not a perfect indicator of obesity or risk. Because BMI is a measurement that uses only a person’s height and weight, it doesn’t account for other factors such as body composition. For example, BMI could misclassify a person with a lot of lean muscle mass as overweight or obese. BMI also doesn’t account for body shape. People who have abdominal obesity, often referred to as being “apple-shaped” are at an increased risk for many health conditions, compared to people who carry their weight in their hips and thighs (or ‘pear-shaped’).

An alternative measure of body size, called a Body Shape Index (ABSI), takes into account the risks of abdominal obesity. New research underlines the importance of ABSI as a predictor of mortality. A study of more than 7000 people showed that death rates went up by a factor of 1.13 for each standard deviation increase in ABSI. Those with ABSI in the top 20% had death rates 61% higher than those with ABSI in the bottom 20%. Additionally, ABSI outperformed BMI as an indicator of risk of premature death, as well as commonly used measures of abdominal obesity: waist circumference, waist – height ratio, and waist – hip ratio.  In practice, ABSI can be used in combination with BMI to calculate a patient’s risk from abdominal obesity.  You can calculate your ABSI here.

At NYU Langone Weight Management Program, finding the best ways to quantify obesity and related health risk is very important to us. Pinpointing the most accurate measures of obesity will help to identify the patients who are most at risk and those who will benefit most from obesity treatment.  You can learn about the treatment options we offer here, or give us a call at 212-263-3166.