What is BMI & How Body Mass Index is Calculated

What is BMI & How Body Mass Index is Calculated
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Body Mass Index, otherwise known as BMI, is a calculation of your body fat based on your height and weight. Research has begun to indicate that this may no longer be the accurate assessment of your health it was intended to be before, as these calculations have no way to measure the amount of body fat, and because muscle weighs more than fat, you risk showing up with a higher body mass index than necessary.

This online tool is a great BMI calucator. If you do not want to use a BMI calculator, you may use this formula to manually calculate your BMI. Divide your weight in pounds by your height in inches, squared. Then, multiply your result by 703. Remember though it is the same for both adult men and women. An example of a manual calculation is: if you weigh 120 pounds and are 5’4, you would first convert your height to inches, which would be 64. Now, 64^2 is 4096. Divide 120 by 4096 to get .029296875, multiplied by 703 equals: 20.595 which could then be rounded up 21.

So, what does that number mean? Any BMI under 18.5 classifies you as underweight. If you have a BMI between 18.5 and 24.9 means that you are in a normal weight range. If you have a BMI between 25 and 29.9, you are in the overweight range, and anything that is greater than 30 is an indication that you are obese.

All you need to tell you about the accuracy of the Body Mass Index is a mirror, or a measuring tape. If you can see that you have more fat than you probably should, you can guess that the BMI is accurate for you, or if measuring your waist see that it is over 35 inches as a woman or 40 as man, it is accurate for you too. If you know that you are fit and in good shape, you can blame the BMI on the fact that muscle is heavier and makes you appear “fatter” in terms of numbers on the scale.

If you are truly interested in finding out more about your body fat composition, you may want to check out a body fat scale like [this one.](https://www.amazon.com/Tanita-BF680-Scale-Monitor-Athletic/dp/B000094ZGH &tag=brihub02-20 )