For years, the Body Mass Index (BMI) has been the standard for measuring whether someone is underweight, overweight, or obese. You’ve probably seen it on doctor’s charts or health apps. But did you know that BMI was never meant to be a health tool in the first place?

So this week, let’s take a look at where BMI came from—and why it’s time to move on.

Where Did BMI Come From?

The BMI formula—your weight divided by your height squared—was created in the 1830s by a Belgian mathematician named Adolphe Quetelet. He wasn’t a doctor. He was trying to define the “average man” for statistical purposes, not to measure individual health.

Fast forward to the 1970s, and American researcher Ancel Keys brought BMI back into the spotlight. He used it to study obesity in large populations. It was never designed to assess personal health, but it was simple and easy to use—so it stuck.

Why BMI Doesn’t Work Today

Even though BMI is still widely used, it has some serious flaws:

1. It Doesn’t Measure Fat vs. Muscle

BMI treats all weight the same. That means a muscular athlete could be labeled “obese,” while someone with low muscle and high body fat might be considered “healthy.” That’s misleading.

2. It Ignores Where Fat Is Stored

Not all fat is equal. Fat around your organs (called visceral fat) is more dangerous than fat under your skin. BMI can’t tell the difference.

3. It Doesn’t Work for Everyone

BMI was based on white European men. It doesn’t account for differences in body types across races, genders, or ages. Using the same standards for everyone can lead to inaccurate results.

4. It Can Be Harmful

Being labeled “overweight” or “obese” based on BMI alone can lead to body shame, anxiety, and even eating disorders. Health is more than a number.

5. It’s Not a Good Predictor of Health

Studies show that BMI doesn’t reliably predict heart disease, diabetes, or even life expectancy. Other measurements do a better job.

Why Do We Still Use BMI?

If BMI is so flawed, why is it still everywhere—from doctor’s offices to insurance forms?

The answer is simple: BMI is easy, cheap, and fast. All it takes is your height and weight—two numbers that are routinely collected during medical visits. That makes it a convenient tool for large-scale health screenings, research studies, and public health tracking.

It’s also deeply embedded in healthcare systems. Many medical guidelines, insurance policies, and treatment eligibility criteria (like weight-loss medications or surgeries) still rely on BMI cutoffs. Changing these systems takes time, and until better tools are universally adopted, BMI remains the default.

Some experts argue that BMI can still be useful when combined with other health indicators. But on its own, it’s not enough—and it can even be misleading.

So What Should We Use Instead?

Health experts are turning to better tools, like:

• Body fat percentage
• Waist-to-hip ratio
• Muscle mass measurements
• Blood pressure, cholesterol, and other metabolic markers

These give a fuller picture of your health—not just your weight.

BMI has had a long run—from its origins in 19th-century statistics to its widespread use in modern healthcare. But just because something is familiar doesn’t mean it’s effective. As we’ve seen, BMI oversimplifies the complexity of human health, often mislabels people, and can even cause harm.

Yes, it’s still used because it’s quick, cheap, and deeply embedded in medical systems. But that doesn’t make it the best tool. Our bodies are unique, and our health deserves more than a one-size-fits-all formula.

It’s time to move beyond BMI and embrace more accurate, personalized ways to measure wellness—ones that reflect who we truly are, not just what we weigh.