BMI Doesn’t Apply to Everyone, But It Applies to Most
In bariatrics, the entry level indicator of healthy bodyweight is Body Mass Index (BMI). So why do many voice doubts about its effectiveness? The truth is, many factors contribute to our health, and as a result, it is not so simply measured. While BMI may not be the one and only indicator of healthy weight for everyone across the board, it’s still important for most people to take into consideration. We’ll try to clarify why it does or doesn’t apply to different people.
History of Body Mass Index
Originally termed the “Quetelet Index”, BMI was first devised by Adolphe Quetelet in 1832. It wasn’t until Ancel Keys renamed it in 1972 that it acquired the term we’re familiar with today. Body Mass Index is calculated by multiplying your weight in pounds by 703, then dividing the result by the square of your height in inches:
Body Mass Index = weight (lbs) x 703 / height2 (in)
Historical BMI categories:
- Below 18.5 is underweight
- 18.5 to 24.9 is normal, healthy weight
- 25 to 29.9 is considered overweight
- Above 30 is obese
- 35+ is life threatening (morbid) obesity
Why BMI Matters – Especially at 35+
Body Mass Index does have validity in regards to obesity and specifically, obesity in those with a BMI of over 35. It is used as measurement for both doctors and insurance companies to determine if an individual qualifies (usually BMI of 35+) for medical weight loss help (both surgical and non-surgical).
Why this measurement?
- For one thing, all criteria (height and weight) is easy to get and readily available.
- Statistics: Once a Body Mass Index passes 35, a person’s likelyhood of developing conditions such as type 2 diabetes, heart disease, cancer and numerous other life-threatening diseases rise exponentially.
Where BMI Falls Short
Just as one size does not fit all, neither does one method of measuring bodyweight health. Body Mass Index places us into one of several broad bodyweight categories as noted above, but it doesn’t account for everything that contributes to a person’s health.
For example, it doesn’t measure body fat percentage or distribution, nor does it account for race, gender, genetics, or age—all of which play into overall health and fitness. As a result, some healthy people can sometimes end up in an undesirable BMI category such as:
- Muscular athletes – Athletes such as body builders tend to have more muscle mass, which can skew their weight measurement in BMI calculations, potentially putting them in the ‘overweight’ category
- Older individuals – We lose some of our height as we age, which affects our height measurement in BMI calculations; this can inaccurately categorize some people.
So, if you’re wondering about your health, go with your gut and find out your BMI as your first step in your weight loss journey. Why not? It can’t hurt; rather, it could improve—and potentially even save—your life.