The Body Mass Index was created by mathematician Adolphe Quetelet in the 19th century. He wanted to provide a formula that can help health professionals to measure the degree of body weight to help organizations allocate resources better to improve the health of the population. His theory was as height increases, so should weight; thus, the development of the body mass index (BMI).
As technology evolved over the years, so has the type of food available in our markets. People were not only gaining weight in coordination with their growth in height, but are also gaining weight in other means at their height regardless if they are still growing or not.
There are an abundance of scientific research available that show correlation with weight and some chronic conditions; thus, the BMI has been adapted to signify risk for those chronic conditions. The higher the BMI, the greater risk that you have (see image below).
The BMI is used so heavily in the healthcare field and for research purposes; however, how reliable is it?
The BMI does not take into account your body weight in bone, muscle, fat, and water in comparison to your height. The BMI solely relies on your weight as a whole; thus, it is not the best indicator of your overall well-being and should not be solely relied on to determine health status.
If you are curious, the equation to calculate BMI is as follows...
For this example, we will take my (Andrew Akhaphong, Mackenthun's Registered and Licensed Dietitian) information to calculate the BMI.
My weight as of April 2021 is 205 pounds. My height is 68 inches (5'8"). Height squared (multiplied itself twice) is 4624.
To begin, 205 pounds divided by 4624 = 0.044. Take 0.044 multiplied by 703 = 31.2. My BMI is 31.2, according to the chart, is obese.
If you know me, I appear thin for my stature in clothes. I have areas of visible muscle, but also areas of visible fat around my body. I do high-intensity interval training 3 times a week. So how accurate is this BMI of my health status?
Probably not so much. It just tells me my BMI is 31.2. How much is that in bone, fat, muscle, water? The most accurate tool to determine that is the DEXA Scan which is provided as a paid service at some hospitals or wellness centers.
The best indicator in general is if you are fitting in your clothes more loosely, or, if you find yourself fitting in old clothes you could not fit in before, it is a sign that what you are doing is resulting in weight loss!