Why BMI is not accurate!

Body Mass Index (BMI) is a way to measure whether or not a person is underweight, overweight or normal weight. It is a calculation that evaluates body mass compared to height. It is widely used to determine if people fall within a weight range that is healthy.

We are living in a time where our health and wellness is our main priority and the visual images put forth in the media are that of super skinny women and body builder men, which can make us normal people feel a bit self-conscious. Recently, a few actors and models have come forward to show the contrast between their photo shopped selves and what they look like before alteration. However, it is difficult to remember when we open a magazine that we are looking at an artistic creation, not a true reflection of the real world. A measurement like BMI can bring us back to reality with a more realistic assessment of what it means to be healthy. It can also enlighten us to the reality of weight problems. Having said that, BMI does have its limitations.

BMI needs to be taken with a grain of salt and a person needs to be honest with themselves in evaluating their own muscle mass. This can be difficult as not only do people overestimate the amount of muscle they have, they also underestimate it.

The equation to determine BMI is weight divided by height squared.

So the first thing we need to do is determine our height squared. For example, multiply your height by itself (1.625 x 1.625) which equals 2.64. And the final step is then to divide your weight (54kgs) by your height squared (2.64). This means your BMI is 20.45.

Determine Your BMI

But here’s the catch. This evaluation doesn’t account for someone’s build. Is the person small boned, stocky or muscular? Having extra kgs of muscle is very different than having extra kgs of fat. Someone who gains weight by muscle lifting will have in increases in BMI, just as someone does who is sedentary and gaining fat. So BMI can be a helpful indicator of health for many, but it doesn’t tell the entire story for everyone. Therefore, it is important when calculating BMI to really evaluate someone’s build. We can quickly see that a body builder is not obese, but muscular. BMI does not evaluate and that is where BMI falls short

There are other, more accurate ways to evaluate body composition. One of the best ways is to measure body fat directly. Excess weight is usually only problematic when it is composed of fat. There are many ways to measure body fat. There is hydraulic testing which involves measuring fat by submerging a person in water. There are Dexa scans, which can also be used to measure bone density and evaluate risk for osteoporosis. A Dexa scan uses beams of light to determine body fat as well as bone density. These methods can give a very accurate reading; however, they also can cost a pretty penny. Skin Calipers are a cheaper method, often used in gyms to pinch the skin and take fat measurements. The skin calipers literally grab the skin and then measure the skin fold. This method is commonly used due to its convenience along with its low price tag. However, because fat is only measured in a few select areas, it is difficult to get a truly accurate reading of overall body fat this way.

For this reason, BMI remains one of the most commonly used measurements to determine body composition unless you have access to an In Body Composition scan.

Our suggestion when looking at a questionable BMI is to confirm with an In Body Composition scan. BMI doesn’t create the entire picture of whether a person is healthy, but it is a convenient tool to start exploring the topic.

For your free In Body scan (Centurion only) and no-obligation consultation contact one of the Diet Doctor’s fat loss coaches on 0788047505 and get your body 2022 ready with a bang.

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