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How to Calculate Bmi

Before sharing the facts on how to figure your body mass index, I decided to have a little play with my ancient calculator and figure my own. Oh, how I wish I had not bothered because I find I have strayed into the unwanted realms of being overweight and so must become a little more careful and just NOT eat that big piece of pie I was so looking forward to.

Most of us know that being 20% or more above the correct weight for height and bone structure means that the label “obese” can be applied. The weight in question here is considered to be excess body fat. Yet athletes and sportsmen and women can often weigh a lot more thanpeople of similar height, build and gender, and can no way be considered obese. On the other hand, some thin people can have layers of surplus fat on their bodies without this being so apparent.

So in fact, the Body Mass Index (BMI) calculation provides a better and more accurate way of working out surplus body fat than just looking at pounds and ounces for a guideline. That is why it is so important to know how to figure your body mass index, and to continue to use it to determine not just weight, but fat losswhile you pursue a healthy eating program. I am off and running in pursuit, even as I type!

To begin with, it would be helpful to state the categories of body weight, as laid down by the BMI.

CATEGORY BODY MASS INDEX
Underweight Under 19
Normal 20 – 25
Overweight 26 – 30
Obese Over 30

The equation for how to figure out your body mass index is really quite simple; I am mathematically challenged, and if I can do it, anyone can. It works as follows:-

WEIGHT (in pounds) X 700
divided by
HEIGHT (in inches) squared.

For example, a person who weighs 176 pounds and is 5’3″ in height would have a BMI of 31.1. They have strayed into the “obese” category. Here is the calculation to clarify.

176 pounds x 700 divided by 63×63 = 31.1

An easy way to do it, using a little basic calculator, is to first multiply your height by your height and make a note of the figure. Then multiply your weight by 700 and complete your calculation by dividing that figure by the height result. You will have successfully figured out your BMI and can see at a glance which category you fit into. If you want to figure out how many pounds you need to lose to get into the “normal” category range of between 20 – 25, play around with the weight figure, reducing it by pounds until you reach that desired state.

If you look at the person cited in the example here, they would need to lose 36 pounds to achieve a BMI of 24.69, bringing them just into the normal weight category. But do remember that if you are a very muscular, well-toned person with scarcely an ounce of fat on your person, your BMI might be lying! Sadly, for most of us this is not the case, and so knowing how to figure your body mass index is a useful weapon in the armoury of fat-fighting.