At 260lbs, Devon Kennard’s body fat percentage tells a different story than his BMI.
For decades, weight has been the gold standard in assessing health. For the most part, with us thinking that the less you weigh, the healthier you are. Or at least, that’s what we’ve been taught—because the opposite can cause serious health problems. When you’re overweight or obese, you may have a higher chance of developing diabetes, heart problems, sleep apnea, metabolic syndrome, and other diseases or discomforts that impact your quality of life. But does being overweight still mean what it used to? And more importantly, is there a better, more confident way to assess health beyond the scale?
Spoiler alert: The answers are no and yes, respectively.
Luckily, more health experts are agreeing that the standards of health should go beyond weight. At Fitnescity, we know the better way to assess health is to understand the total body composition—the numbers behind the weight.
Is Weight Just a Number?
We give a lot of weight (pun intended) to what the scale says. Chances are, your doctor has at some point shared with you what a healthy weight is based on your height, likely using the MetLife height/weight tables (created in 1943, mind you). But we’ve come to know that the number on the scale doesn’t tell the whole story.
For starters, two people of the same weight can have very different body types and sizes. Genetics play a big role here: some people just have smaller bodies while others have larger bodies, no matter what they eat or how much they exercise—and BOTH can be healthy or unhealthy. But weight doesn’t take these differences into account.
Body mass index (BMI) is also outdated because it can’t tell a person’s body fat percentage apart from their muscle content. Two people may have very similar weights and BMIs, but for very different reasons. It’s like comparing your Uncle Joe Smith, who is 5’10” and 260 pounds and enjoys Big Macs and beers with the boys every weekend, to Arizona Cardinals’ Devon Kennard, who is 6’3”, 260 pounds, and in the gym every day. It’s just not a fair comparison!
Also, the standards for a healthy body weight are based on the Caucasian body type. It’s been well-studied that the risk of developing some serious health problems, such as diabetes and heart disease, increases alongside your BMI. But research also shows that these risks are higher in some ethnic groups.
For example, findings shared by the Harvard School of Public Health noted a number of differences across different ethnic groups:
Asians have higher weight-related risks of disease at lower BMIs
Compared to white Europeans of the same BMIs, Asians have 3-5% more body fat.
South Asians are more prone to develop abdominal obesity.
Black individuals often have lower body fat and higher lean muscle compared to White individuals of the same BMI, which may put them at a lower risk of obesity-related diseases.
Last but not least, weight doesn’t take into account the full picture of health, such as good eating and drinking habits, exercise, sleep, etc. There’s an old saying that “Abs are made in the kitchen, not the gym,” and it holds some truth. In terms of health, what you eat matters even more than how much you exercise (even though both are important).
Body Composition: A More Realistic Image of Health
Neither weight nor BMI account for your body composition—it is rather the amount of muscle, subcutaneous fat, and visceral fat which define your body’s makeup. Body composition will vary from person to person, including those who are the same height and weight.
In the example of Uncle Joe Smith and Devon Kennard, it can be worrisome that their matching heights (6’3) and weights (260lbs) would place them in the same category as being overweight or even obese.
The same is true for those who fall into the ‘healthy’ category of the BMI but actually have very poor diet and exercise habits. This classification of being ‘healthy’ could mean the person is not alerted to the fact that he or she might have dangerous levels of visceral fat. This scenario, also called “skinny fat,” is when a person has a high percentage of body fat and very low muscle mass.
Because fat and muscle percentages can’t be measured by weigh-ins on a scale, body composition scans like the DEXA or BOD POD are becoming more realistic indicators of health. It’s not “weight” itself that makes us unhealthy—fat is the real problem.
For example, too much body fat can:
Increase your cholesterol (the bad kind)
Limit your blood’s ability to clot
Put unnecessary stress on your bones, especially the back, hips, and knees
Decrease your sleep quality
Affect your hormones, especially insulin and how your body uses it
Strangle your organs, especially your kidneys, heart, and liver
Putting weight to the side for a moment, we can learn so much more about our bodies when we understand body composition. Dropping or gaining a few pounds does not just change our body composition, but can then affect our health.
What Are Body Composition Scans?
Because the scale can’t accurately break down the percentage of fat, muscle mass, and bone in your body, we can turn to the DEXA scan for a more in-depth snapshot.
DEXA stands for Dual X-Ray Absorptiometry. It uses low-level X-rays to see and measure how much bone, muscle, and fat is in your body. The scan takes images of the body, then translates those images into numerical and graphical data. The procedure is quick, painless, and extremely useful in learning more about your unique health profile beyond your weight.
How does a DEXA scan work, you ask? It’s actually quite simple (for you, that is):
After laying down on the machine, the scan starts and an “arm” will pass over your body. This is the X-ray at work, taking images and turning them into data.
We Did a Body Composition Scan on Devon Kennard: Here’s What We Found
Fitnescity recently performed a DEXA scan on Arizona Cardinals offensive linebacker, Devon Kennard. Devon is 6’3” and 260 pounds, works out daily, and follows an eating regimen that allows him to be at peak performance in the NFL.
According to our BMI calculator, Devon would need to lose 60 pounds to be considered a “healthy” weight for his height.
But after the DEXA scan, the scan showed that Devon had a body fat percentage of 15.4%. This places him in the 5th percentile in his age group. To put it another way, 95% of individuals in Devon’s age group have a higher body fat percentage.
Devon’s impressive body composition is no surprise when we consider his line of work. Being an offensive linebacker isn’t a job for the weak. Getting routine DEXA scans as part of his fitness strategy can help him learn if and how his body composition changes over time.
Benefits of Body Composition vs. Weight
We already know about the risks involved with having too much body fat. Breaking down your body’s composition by muscle percentage and fat percentage can help you set better goals so you can become healthier on the inside.
You can also start prioritizing the right actions and objectives to reach those goals when you know your unique body composition. For instance, if you have a high percentage of body fat, then you might include more strength training exercises in your workouts to build more muscle, which will, in turn, increase your resting metabolic rate and help you burn more calories. Otherwise, if you’re only focused on losing weight (versus losing fat), you might end up sacrificing your muscle in the process. Under-eating as a method for losing weight can also have detrimental effects on your metabolic rate by slowing it down.
Body composition scans can also monitor progress. While getting a scan is a great starting point for your health journey (particularly for setting goals), getting an updated DEXA scan every 3-6 months will keep you accountable and show you exactly how much your body has changed on the inside. You can actually start to understand how your diet and exercise habits are helping you not only lose fat but also gain muscle.
Keep in mind that the same volume of muscle weighs more than fat. Or, to put another way, five pounds of muscle will take up less space in your body than five pounds of fat. That’s why the numbers on the scale don’t always change, even when your body is making healthy shifts on the inside.
The bottom line: DEXA scans are tailored to your body. Every person is unique - and your genetics, ethnicity, body size, and health habits won’t always fit into a specific set of standards.
Weight matters, but don’t equate a certain number on the scale to health.
Next Week - Devon Kennard’s Resting Metabolic Rate
Devon does not want to rely on predictions and estimates when it comes to how many calories his body needs. Next week we will look at Devon’s actual RMR, and see how that compares to the long-used equations.
Ready for your next test? Schedule here.
Sources:
https://www.scientificamerican.com/article/can-you-be-healthy-at-any-size
https://www.wellnessminneapolis.com/drbarrettblog/body-size-does-not-equal-health
https://www.npr.org/templates/story/story.php?storyId=128267723
https://www.niddk.nih.gov/health-information/weight-management/adult-overweight-obesity/health-risks
https://www.healthline.com/health/fitness/skinny-fat
http://www.assessmentpsychology.com/metlife.htm
https://www.webmd.com/fitness-exercise/difference-between-bmr-and-rmr