With obesity still a major health problem worldwide, and even with some success using new and very expensive treatments such as GLP-1 injections, there continues to be a need to easily determine your ideal healthy body weight. If you are overweight, why not set a goal of working on it until you reach your ideal weight?
Before beginning a weight loss program, I recommend having a baseline measurement so you can document your progress. For years, I have recommended the body mass index (BMI), which can be readily determined by doing a simple online search for a BMI calculator, then entering your height in inches and weight in pounds to get your BMI. The levels vary from normal (18-25), overweight (25.1-30.0), obese (30.1-35.0) and morbidly obese (greater than 35.0). To calculate BMI on your own, divide your weight in pounds by your height in inches2 (squared). Multiply that result by 703 to get your BMI.
However, your BMI calculation does not distinguish between fat and muscle mass and does not consider the dangerous visceral fat. Visceral fat, which often appears as a “pot belly,” can also lie hidden inside as it surrounds or involves the organs in the abdominal cavity. This type of fat is more dangerous than subcutaneous fat (the layer just underneath the skin) because it raises the risk of serious medical issues. For example, an obese person could have the same BMI as a bodybuilder. Also, the BMI considers the body to be a cylinder, or tube, even though many people have a large waist circumference. One way to account for this—since our bodies are not cylindrical but can have large abdomens where visceral fat is located (“pot bellies”)—is to measure your waist circumference while standing, at the end of an exhale and at the level of the navel. Then determine your height in inches or centimeters, divide by 2, and that should be the maximum your waist circumference should be.
Waist circumference for men should be less than 40 inches and for women less than 35 inches. This new standard for measuring visceral fat is called the Body Roundness Index (BRI). The BRI was found to be superior to the BMI because visceral fat is directly associated with health problems such as cardiovascular disease, kidney disease and even cancer. The BRI measurement can help estimate your visceral fat whether you are thin (ectomorph), within normal range (mesomorph) or obese (endomorph).
This measurement was first reported in 2013 by the mathematician Diana Thomas and colleagues in an analysis of three databases from studies of demographics and anthropometrics, fat mass and visceral fat volume. Thomas’ group visualized that the body shape is an egg or ellipse rather than a tube or cylinder in the calculation of ideal weight. To calculate your BRI and percentage of visceral fat, search “BRI calculator” online and enter your waist circumference, hip circumference, age, sex, body weight and height. Values vary from 1 to 20 (1 equals a narrow body and 20 or more equals a round, obese body).
Most people are between 1 and 10, and the average American adult has a BRI of around 5. But a study released last year and posted online by the Journal of the American Medical Association (JAMA) reported that those with BRI below 3.4 and above 6.9 were at the greatest risk of premature death.
BRI proved most effective in predicting risk of developing nonalcoholic fatty liver disease (NAFLD), which I discussed in a July 2023 article in Decision. BRI could be the next noninvasive and easily attainable screening tool for mortality risks pending more research.
Those at most risk, according to the National Health and Nutrition Examination Survey (NHANES) health database, have a steady increase in BRI and tend to be women, the elderly and Mexican Americans.
To sum it up, the best way to estimate the amount of visceral or bad fat is the BRI, while the BMI is still used to calculate ideal body weight and continues to be an important indicator of future health problems. Both tools are important with our nation’s increasing obesity epidemic. Although BRI is far from commonplace today, the goal is for researchers to conduct more studies on this technique of measuring body composition with the hope that someday it will be incorporated into your annual check-up with your primary care provider.
Both BMI and BRI are values of describing your overall health. When combined with a healthy diet, exercise, supplementation, cutting back on alcohol, not smoking, managing stress and prioritizing sleep, they can help you stay informed of your key risk factors while working toward a healthier lifestyle (To see my 8 Healthy Steps, visit cooperaerobics.com/blog/8-healthy.).
And remember, as I have written repeatedly in my articles here, your health and longevity are your responsibility, not the insurance company, the government or even your personal physician (unless he or she is trained in the field of preventive medicine), and no drug can replicate the benefits of an active lifestyle.
See what the Word of God says: “Don’t you realize that your body is a temple of the Holy Spirit, who lives in you and was given to you by God? You do not belong to yourself, for God bought you with a high price. So you must honor God with your body” (1 Corinthians 6:19-20). ©2025 Kenneth H. Cooper
Kenneth H. Cooper, M.D., MPH, known worldwide as “the father of aerobics,” is the founder and chairman of Cooper Aerobics in Dallas and chairman emeritus of The Kenneth H. Cooper Institute.
Scripture quotations are taken from The Holy Bible, New Living Translation.