Understanding BMI

When we think about health measurements, we hear BMI a lot. What exactly is it and is it an accurate way to measure our health?

What is BMI:

BMI stands for Body Mass Index. It’s a calculation of height divided by weight in pounds, times 703 that Doctor’s offices often use. There are many BMI calculators online to check your own without having to do the math! See the chart below for the ranges to determine where you fall.

What you should know:

BMI is a starting block for understanding your overall health. BMI does leave out some important factors.

When understanding fat, it is important to understand the two types of fats that the body carries. There is visceral fat and subcutaneous fat. Subcutaneous fat is the fat that sits right under our skin-think cellulite. It’s stubborn to get rid of but doesn’t bother our bodies. Visceral fat on the other hand is different. Found in the abdominal cavity around the organs, visceral fat is more dangerous because it secretes waste that can lead to chronic diseases like heart disease. But with a healthy diet and exercise, visceral fat is easier to lose than subcutaneous fat.

What does this have to do with BMI? When we only look at BMI it does not consider what type of fat is in our body. This can leave us with an incomplete picture.  You may have a low BMI but carry excess weight in the belly area. This is where another simpler way to measure your health comes into play. Waist circumference. Simply put, it’s measuring your waist. For women, it should be less than 35 inches, and for men, it should be less than 40.

One other point about BMI, on the flip side of abdominal fat, is muscle. For very active, muscular individuals BMI may not be as accurate because muscle weighs more than fat. So, another reason to check that waist circumference.

Here is the health coach take away: Understand what your BMI is and measure your waist. Use those numbers together as a place to start to get a clear picture of your overall health. The closer you are to “normal” BMI ranges and waist circumference the less likely you are to develop serious chronic health issues. 


Under Weight Under 18.5
Normal Weight 18.5-24.9
Overweight 25-29.9
Obese Over 30