So a number of fatties have now blogged on the topic of the truly awful calculator on the BBC health site (no, I won’t link to it, it’s awful, but not hard to find) that tells you your BMI, what percentage of the population of your country and the world you have a BMI higher than, what country’s population your BMI is closest to, and how much tonnage would be added to the earth if everybody had the same BMI you do.
It’s awful, but the bad science is actually pretty funny.
Lots and lots of people have been told that they have BMIs higher than 100% of the population, which would seem to indicate that we’re each the fattest person in the world. My own is higher than 99% of the US, but 100% of the world, so I’m the fattest person on earth, but not the fattest in the country. This alone provokes sniggers.
But it’s the “If everyone in the world had the same BMI as you, it would add 214,351,019 tonnes to the total weight of the world’s population,” that is truly hilarious. Because, of course, it is blatantly false. Completely made up. Physically impossible.
Fat people do not spontaneously generate matter or magically teleport it into our bodies from deep space. You can’t add mass to the earth without getting it from somewhere else, like a meteor strike* or mining it from asteroids and bringing it back. Any mass added to fat people’s bodies has to come from something else on the planet.
But let’s assume for the moment that the unicorn fat people who add extra mass to the planet exist. Let’s look at those numbers, shall we?
214,351,019 tonnes is equal to 217,790,690,253kg. The earth masses 5.9736×1024. The amount that everyone being unicorn fatties would add is, according to my calculations, four hundred-trillionths of the mass of the planet. That’s 0.000000000004%. To Mother Earth, it would be like me gaining 0.00000000000936 of a pound, which my body probably fluctuates by every few breaths just by respiration and perspiration. If I pee 6oz next time I go to the bathroom, that’s 0.375lb. See the difference?
It’s meant to be this huge, scary number. OMG, we would make the earth so much heavier if everybody were as fat as me! No, we wouldn’t. Not by any stretch of the imagination.
I’ve said it before and I’ll say it again: If they were right, they wouldn’t need to lie. And they do it all the time.
*Not at all uncommon. Some estimates of weight added to the earth by meteors and meteor dust go as high as 100,00 tons per years. It’s nothing by the standards of the planet, of course, just as the weight of the dust that settles on you in an hour is nothing to you.