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Body Mass Index (BMI)

What’s your ideal weight? The Body Mass Index (BMI) is a mathematical equation that is supposed to tell you whether you have the ideal weight for your height. Does it work? Let’s investigate…

Adolphe's Equation

It was 1830 when a famous mathematician from Belgium named Adolphe Quetelet came up with the BMI equation. This is how you do it:

Weigh yourself in pounds (lbs)
Find your height (inches)
[Weight / (Height x Height)] x 703 = BMI

Now once you have your answer, there is a chart where you can find your number and it will tell you if you are the ideal weight for your height. Here are the results:

Less than 15 = Anorexic
15-18.49 = Underweight
18.5 - 25 = Ideal
25 – 30 = Overweight
30 – 40 = Obese
More than 40 = Morbidly Obese

Extra Experiment

Hmm, I am a little skeptical about this formula and results. How could this chart determine whether someone is obese without considering how much body fat someone has compared to their muscle mass? Muscles weigh more than body fat so would that be fair to people with lots of muscles? Just for fun, let’s experiment and see how some famous athletes match up to these results.

Tom Brady (quarterback for New England Patriots)

[225 lbs / (76 x 76 inches)] x 703 = 27 - Overweight

Kobe Bryant (Point Guard for the Los Angeles Lakers)

[200 lbs / (78 x 78 inches)] x 703 = 25 – Overweight

Serena Williams (the tennis player)

[178 lbs / 70 x 70 inches] x 703 = 25.5 - Overweight

Whaaa??!?! It seems like these amazing athletes have a huge disadvantage. Well, it’s probably because they have so much muscle and muscle weighs much more than fat, so the BMI doesn’t really work for you if you have muscles. Let’s see how it would work for someone a little more normal… how about a famous actor?

Tom Cruise (the actor)

[201 lbs / (67 x 67 inches)] x 703 = 31 – OBESE???

OMG! If Tom Cruise is obese, maybe the equation doesn’t work very well for short guys either. Let’s try someone else we can all relate to…

Justin Bieber (the singer)

[130 lbs / (65 x 65)] x 703 = 21 - IDEAL!!!

Kidsworld Conclusion

Hooray, so I guess if you are a singer with a cute haircut, the BMI is a perfect chart to help you find out if you are at your ideal weight... Uhhhh anyways, maybe since this equation was invented over 150 years ago, we should invent a new method. People have changed a lot in the past century. We eat differently, we play more sports, as more cultures combine in America, our bodies are changing. The BMI is total BS!