I went from very obese to obese, I'll take it LOL
Your new BMI: 39.31
Your old BMI: 40.32

For those of you who aren't quite so nerdy, what Devlin says in this article is that the BMI is, in its essence, a quick and dirty way of estimating the measurement of people's waistlines given that historical medical records don't usually track that information. (I've tried this out. I've divided my BMI by my waist measurement for a number of different moments in time, and I always get close to the same number.)

Devlin's article has thoroughly convinced me of the value and limits of BMI: It's like a waistline measurement, but not as good, and subject to all the limits of waistline measurement. The thing to remember with BMI is "quick and dirty" or, to quote the BBC, "cheap and cheerful." I wouldn't even dream of using it as a the way of determining if I were healthy or fat or anything else, since I have a whole bunch of more precise measurements at my disposal for that.

Rant over. Thanks for listening.

It says my new healthy weight range is between 36 and 48 kg.
I disapprove of that. I have been under 40 kgs once and it was visibly underweight.....

Everyone wants to complain about BMI when its inventors - and maintainers - only meant it as a tool for populations. They clearly can't take detailed arm/waist/thigh measurements of everyone, or put them in a Bod Pod. And mortality/morbidity wise, there are trends. It gives them SOME information.

Of course personal body fat measurements and individualized attention is better for individuals. Do people expect epidemiologists and statisticians to be magicians?

I will say that I tend to roll my eyes a bit at the tendency many of us have to say "oh the bottom range of the BMI is just too skinny/I look gaunt there/the overweight range is actually healthy for me because of my big bones." You have got to remind yourself - forcibly if necessary - that you have grown up in a society where over half of adults are carrying too much fat. Your internal visual gauges are different than they would be if you grew up in Paris or Japan. Also, if you've always been over 200lbs, imagining yourself at 120 is just... foreign. 150 or 160 feels safer, more achievable, less foreign. Doesn't actually mean that you couldn't be healthy lower and that your ideal weight might not be lower. I don't know, only you being honest with yourself can know.

There is a thread in the Goal forum of a British girl who lost 100ish lbs. After the first 50, she looked great! My American eyes were very happy with how she looked, and would not have thought that she could lose another 50 and still look wonderful. Well, she did, and it really helped me reassess my own goals.

Old BMI - 30.45
New BMI - 30.81

I've been saying this for years. The basic flaw in the BMI is it uses height squared. By using only 2 dimensions it suggests that tall people must be exactly the same width as a short person and that's not true. Compare my body and body parts and it's bigger in all 3 dimensions and much of that is bone and frame mass that I can't shed my dieting.

I will also grant, however, that a typical tall person also is not like a uniformly scaled up shorter person either, so neither can you use height cubed.

I see he compromised with taking height to the 2.5 power. Makes sense, but I would like to see how well correlated it is with epidemiological data showing the health benefits of different body weights, because that would help support his case.

For what it's worth, my BMI went down more than 2 points with this new chart... takes me out of "obese" and into "overweight" even.

Math, is math. You can't argue with the proven formula. Like "pie".

I believe it was Newton who said, if a force, hits a solid object, you will get an equal and opposite force reaction. Or something along that line. (feel free to correct this)

The thing is, when it comes to "ideal" or "range" in just the human population, we all differ so much, in size, shape, and so on, the BMI, as it stands is a crappy math formula.

My older son, 34 years old, is a State Trooper, DOT Sargent, and a SWAT sniper. He is 5'11", 185 pounds, there is very little fat on him. He's built like a brick, "sh*t house!

But, according to BMI, he's fat! LOL! He's just one of those people, that has lots of muscle.
He can still bench 250#, sqaut, #300 and run the 400 meters, in 60 seconds. Plus lets add on repelling out of a helicopter and busting down doors, and so on.

Fiddle, I can dead lift more than I weigh! I work for a veterinarian, and that job, because we do small and large animal, means I need to be able to move it, and lift, and dodge, not only cats, and small dogs, but 1000# plus horses and cows, and so on. Yet at 5'5" AND 55 years old, 140#, my BMI, according to the math, barely puts me in the good zone.

In my opinion, the BMI thing, is something the insurance industry invented!

I'm pleased, still overweight, but my BMI is now 27.5 instead of the 28 it was. I'm hoping to hit under 23 BMI, juts a dream
And i don't get to a size 10 unless I'm around 160s weight wise. I guess I carry it all in my butt, though I thought I was pretty even in the curves.

I don't see myself nor care in getting into the healthy range as i feel fantastic and a long way from where i started which was CLass III Morbid Obesity (60.2)