Beyond the BMI: A Smarter Look at Weight & Health

Many patients ask me what their BMI is and what it should be. This is essentially another way of asking what they “should” weigh, since BMI is simply a calculation of weight relative to height, which remains constant in adulthood.

I tell them that I don’t answer that question directly—because there’s a lot more to the story. Here’s what I focus on instead.

What’s Wrong with the BMI

The Body Mass Index (BMI) was developed based on data from European men, yet it’s applied across all populations. It’s calculated by dividing weight in kilograms by height in meters squared. That’s it. It doesn’t account for gender, race, body composition, fat distribution, or metabolic health.

So why do we still use it?Simply put, it’s better than nothing—especially for large population studies assessing risk trends. But for evaluating an individual patient and guiding medical treatment, we have much better tools—if you know how to use them.

What’s Right with the BMI

BMI does tell you your weight in proportion to your height, which is useful in some contexts. Specifically, when we're concerned about the health effects of excess weight itself.

💡 Reminder: Weight is force—defined as mass multiplied by gravity.

Excess force on the body increases the risk of several health issues, including:

• Skeletal stress: Joint pain, arthritis, degenerative disc disease

• Respiratory stress: Obstructive sleep apnea due to pressure on the neck and diaphragm

• Cardiovascular stress: Thickening of the heart muscle, systemic and pulmonary hypertension

Patients with a BMI over 40 often experience these complications. Interestingly, many also have both excess muscle and fat.

I frequently hear patients with higher BMIs say their labs are “normal,” and they’re surprised—sometimes even told by doctors they’re “surprisingly healthy for their weight.”

So yes, a high BMI can indicate risk from excess weight—but it can also suggest protective skeletal muscle mass, which helps guard against insulin resistance and type 2 diabetes. This is part of the “obesity paradox.”

That said, not everyone with a high BMI has excess muscle. But if your weight is evenly distributed throughout your body—you probably do.

Body Composition

Body composition testing looks beyond the scale, revealing how much of your weight is:

• Fat

• Lean mass (muscle, organs)

• Water

But even this isn’t the full picture. Once you understand your fat-to-lean ratio, the next step is to look at:

• The type of fat

• The location of fat on the body

Body Weight Distribution

Neither BMI nor body composition alone tells us where your weight is distributed—and location matters.

• Upper body weight is linked to higher metabolic risk.

• Lower body weight is more likely to lead to joint issues like knee or hip pain, but not metabolic disease.

This is because upper-body fat surrounds and affects vital organs (like the liver, pancreas, and lungs), whereas lower-body fat is anatomically separated.

🔍 How to Assess Weight Distribution:

• Waist-to-hip ratio

• InBody or Seca scans

• DEXA scan with regional analysis

Adipose Tissue Type: Subcutaneous vs. Visceral Fat

It’s normal for adult women to have up to 32% body fat, and men up to 20%. This fat is typically subcutaneous—stored just under the skin as passive energy.

But visceral fat is different:

• Lives inside the abdominal/thoracic cavity

• Infiltrates vital organs

• Secretes inflammatory chemicals (adipokines)

• Contributes to metabolic dysfunction

You can measure visceral fat with:

• DEXA

• CT or MRI

• Advanced InBody/Seca models

Blood Work and Metabolic Health

Want to understand your metabolic function beyond your weight?

Start with:

• Lipid panel

• Liver function tests

• Fasting glucose

• Urine analysis

Then consider advanced markers:

• Hemoglobin A1c

• Fasting insulin

• CRP or other inflammation tests

🔗 Check out my blog on lipid panel interpretation for a deep dive.

Symptoms Matter, Too

Let’s not forget the basics: How do you feel?

• Are you tired?

• In pain?

• Not feeling as strong or fit as you'd like?

• Unable to do the things you enjoy?

These concerns may or may not be tied to weight, but they’re crucial. If there’s something we can do to improve your quality of life—let’s do it.

We’ve Come a Long Way Since the BMI

There are better tools. There are more meaningful questions. You deserve a personalized, compassionate approach to health—not just a number on a chart.

Take Back Your Health Goals,

Valerie Hope-Slocum Sutherland, MD