It’s time to talk about a number that’s been following you around since your service days - BMI (Body Mass Index). But does it really tell the whole story?

Let’s break it down.

What is BMI?

BMI is a simple formula that takes your weight in kilograms and divides it by your height in meters squared. The result puts you in one of four categories: underweight, normal weight, overweight, or obese.

These categories are used as a basic screening to determine whether or not a person is at a healthy weight.

Why is BMI Used?

Healthcare providers and researchers like BMI because it's quick, easy, and doesn't require special equipment. It's been around since the 1830s and has been widely adopted as a general health indicator. For population studies, it can provide useful data.

The Problems with BMI

BMI is useful as a screening tool, but it shouldn’t be the only metric used to assess health.

Here are 3 reasons why:

BMI Doesn’t Account for Muscle Mass
BMI doesn’t differentiate between muscle and fat.
Muscle is denser than fat. As a result, it weighs more per square inch than fat. People with more muscle tend to have higher BMI readings even though they’re in great physical shape.
Studies have shown that athletes with high muscle mass, who weigh more as a result, are often classified as “overweight” or even “obese” by BMI standards.
BMI Overlooks Fat Distribution
Where fat is stored on your body is just as important as how much you have.
Visceral fat (fat around your organs) is linked to higher risks of heart disease and diabetes.
Subcutaneous fat (stored underneath your skin) causes spare tires and thunder thighs but doesn’t have the same associated health risk.
BMI doesn’t account for where fat is distributed in your body which is critical in determining health risks.
BMI is a One-Size-Fits-All Measurement
BMI uses the same calculation for everyone, regardless of age, gender, or body composition. It doesn’t account for the natural changes our bodies go through as we age or the differences between men and women.
It’s a fact that, as we age, our bodies naturally lose muscle mass. It’s a process called sarcopenia. Research suggests men and women lose 3-8% of their muscle mass each decade beginning at 30.
What’s more, women tend to carry more fat than men.

So, What Should You Do?

Don't throw out BMI entirely, but don't let it be the only measure of your health. Consider adding these additional assessments for a comprehensive view of your health:

Body Fat Percentage
This gives you a more accurate picture of your fat-to-muscle ratio.
Waist-to-Hip Ratio
A better indicator of where you're carrying fat and potential health risks.
Fitness Assessments
How's your endurance? Your strength? These functional measures tell you more about your overall health than a single number.
Regular Check-ups
Blood tests, blood pressure readings, and discussions with your healthcare provider give a more comprehensive view of your health.

Remember, your health is about how you feel, how you perform, and how you live your life. Keep pushing yourself, stay active, and get after it.

Want to level up your fitness game?

Join the Functional Fitness Activity Group in the Team RWB Member App and connect with service members from all branches and eras. They share workouts, tips and information to help you achieve your fitness goals.

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