Body Mass Index Chart Limitations

30 scale


This will probably come as a shock, but if you walk into any mainstream gym, the vast majority of people are there to lose weight. Yes I know what you are thinking but it’s true.

In all seriousness though, there are so many people that are overly concerned with their weight. Now I’m not saying that being fat is a good thing though, but total body weight is not always a good indicator of how healthy a person is.

For example when I client comes to me and tells me that they want to lose 20 pounds many times I will ask them if weight is really that important or do they want to fit into a certain size and have their waist be a certain amount if inches and just look and feel better. The majority of the time, they want the latter.

Sometimes I will even ask them if they weighed 400 pounds but were ripped and fit into the size they wanted and looked good would it really matter what they weighed. For some people like athletes that compete in a sport where there are weight classes, weight is a valid concern. For the average person their overall weight should not be the primary focus of their nutrition plan or their workout.

I try to get people to focus on their body fat percent because this is a much better indicator of obesity, and a good measure of how ‘healthy’ someone is. A combination of bodyweight and body fat percentage will allow a person to have a rough estimate of their fat mass and lean body mass (muscle, bones, organs, etc.)

Even after explaining this to hundreds and hundreds of people, it still surprises me when someone asks me if they are at a ‘healthy’ weight or what is their BMI. Most of the time I just tell them that they don’t need to worry about that right now and they should focus on the body fat percent.


Analyzing the Old School Method

The BMI (Body Mass Index) is one of the most commonly used, yet outdated, ways to measure how “healthy” your weight is. This formula was derived in the mid-1800s by Lambert Adolphe Jacques Quetelet. Even though this formula was developed over 150 years ago and was never intended as a measure of health, it still baffles me as to why some doctors and most insurance companies use this archaic formula.

Basically the BMI takes your height and weight and calculates how healthy you are based on the formula. The formula is as follows:

30 - bmi formula

There are a few different standards on what is healthy and not healthy based on the BMI. A simple chart is below but may vary slightly depending on what country you live in.

Underweight = <18.5
Normal weight = 18.5–24.9
Overweight = 25–29.9
Obesity = BMI of 30 or greater

30 BMI chart


The BMI Limitations

If you are someone who is an athlete or has a lot of muscle you may already see some flaws with the BMI formula.

Air Jordan Chicago Bulls

Michael Jordan had a BMI of 25 which would classify him as overweight.

The problem is that the BMI formula does not take into account where the weight is coming from. If you have a lot of muscle or very dense bones, (as is the case with most athletes) your BMI will measure high and overweight or obese. So someone who works out, plays a sport or is really active may have a high BMI but be perfectly healthy.

On the flip side some people may have a lot of body fat and very little muscle (also called skinny fat.) This person may register normal on the BMI index but their body fat percentage may be very high and unhealthy.

At the time of this writing my BMI is around 29, which would put me very close to the obese category even though my bodyfat percentage is around 11%.

While I have been started bulking and would not consider myself “ripped” at the moment, I would definitely not consider myself being nearly obese which is why I say no to the BMI chart and why you should as well.


The BMI of Some Athletes

Just for fun I thought I’d look up the heights and weights of some athletes and see what their BMIs were. Some athletes like Michael Phelps and Usain Bolt had normal range BMIs. Other athletes that had more muscle on them would be considered overweight or obese by BMI standards. I listed a few of them below. I don’t think any of them look unhealthy and some of them are actually pretty ripped.

NameHeight (feet/inches)Weight (pounds)BMIRating
LeBron James6’8”25027.5Overweight
Kevin Durant6’9”24025.7Overweight
Michael Jordan (during career)6’6”21625Overweight
Aaron Rodgers6’2”22528.9Overweight
Marshawn Lynch5’11”21530Obese
Calvin Johnson6’5”23628Overweight
Larry Fitzgerald6’3”21827.2Overweight
Peyton Manning6’5”23027.3Overweight
Sidney Crosby5’11”20027.9Overweight
Cain Velasquez6’1”24131.8Obese
Jon Jones6’4”20525Overweight
Arnold Schwarzenegger (while bodybuilding)6’2”25032.1Obese

If you know what some of these guys look like you can see how ridiculous the BMI measurement is. Michael Jordan was shredded when he played and he’s definitely not at an unhealthy weight. No one in their right mind would think LeBron James or Calvin Johnson are unhealthy either.

If it gives such inaccurate results, why is it still used?

Both Calvin Johnson (left) and Larry Fitzgerald (right) have overweight BMIs.

Both Calvin Johnson (left) and Larry Fitzgerald (right) have overweight BMIs.

The reason it’s use affects you is that medical professionals and insurance companies can use this data to jack up your rates if you are an athlete or someone that is healthy body fat percent but a high BMI.

I think the biggest reason that people still rely on the BMI is for 2 reasons… cost and convenience.

When you ask a random person their height and weight, most would be able to give you an answer. A smaller percentage would be able to give you their waist and hip circumference measurements and an even smaller number would be able to tell you their body fat percentage.

When doing studies on large groups it is much easier and cheaper for researchers to gather “known” data instead of measuring it. I think it does have some value in this sense but it can result in some inaccurate data that can lead to faulty analysis. I do not think that BMI should be used at an individual level at all.

Remember this formula was developed almost 200 years ago for a relatively sedentary population who did not lift weights and did not have a lot of high-level athletes, yet in 1998 the National Institute of Health (NIH) announced their guidelines for BMI levels. Yes 1998. That’s over 150 years after the creator, Quetelet, said this was not an accurate way to measure a person’s fatness level.



What can be done?

UFC Heavyweight Champion Cain Velasquez would be considered obese.

UFC Heavyweight Champion Cain Velasquez would be considered obese.

I think the biggest thing that needs to be done is for people to stop using BMI for measuring how healthy someone is. This especially means the insurance companies since they can just as easily measure someone’s body fat percentage.

I think the mainstream media needs to focus less on BMI and start focusing on more relevant measurements like body fat percentage. Heck even the waist to hip ratio or the waist to height ratio are better indicators of overall health than the BMI.

For the average person who is looking to get in shape, you need to focus on a bodyfat percentage and weight combo that can that can tell you if you are REALLY gaining muscle or losing fat and not just what the scale is telling you.


Wrapping it Up

So I hope this article helps you feel a little better about how much you are weighing or at least helps give you an effective goal to shoot for. If you liked this article share it with your friends on your favorite social media with any of the buttons below.

If you have any questions or comments you can leave them below and you can always reach me on the facebook group. Thanks for reading.