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Dieting & exercise

How good are the BMI tables??

(20 Posts)
Franbern Wed 03-Mar-21 15:47:28

When were these tables worked out and on what basis?

The only time I could ever get inside their healthy weight would be if I was extremely ill!!!

Indeed, the weight they say I should be for my height, etc. would make me seriously and probably dangerously skinny.

A few years back, when I had been very ill with ulcerative colitus -unable to eat very much for some years and getting weaker and weaker, I still did not get out of the BMI table as Overweight!!!

I do know when I am a good weight for me, although that shows as just bordering between overweight and obese on those tables.

Kim19 Wed 03-Mar-21 15:53:50

Don't think I've ever seen it. Probably too frightened!!

NellG Wed 03-Mar-21 15:55:23

I'm currently reading a book that mentions this, apparently the BMI has its origins in a system designed in the 1930's, which solely took measurements from middle aged white men.

I'll try and find the section and post what it says.

AmberSpyglass Wed 03-Mar-21 15:56:03

They’re absolute nonsense - ignore!

growstuff Wed 03-Mar-21 16:00:39

I don't agree that they're absolute nonsense, but should be used in context. Waist size is an important indicator of body fat. Fat round internal organs is more dangerous than fat (or muscle) on the legs or arms.

My BMI is fine, but I know I'd benefit from losing 4-5 kilos and a few centimetres from my waist.

NellG Wed 03-Mar-21 16:00:55

Found an article that gives the history, which is easier to post than a passage from a Kindle book.

elemental.medium.com/the-bizarre-and-racist-history-of-the-bmi-7d8dc2aa33bb

AGAA4 Wed 03-Mar-21 16:02:36

My son, according to the BMI tables was obese. He trained most days and ran marathons. There wasn't a spare bit of fat on him but it doesn't take into account muscle mass which weighs heavy.

Jaxjacky Wed 03-Mar-21 16:54:15

I’m within my range, just, 5’11 and 12st 5lb. I’ve always used it to keep an eye.

Pantglas2 Wed 03-Mar-21 17:05:17

According to BMI Mike Tyson was overweight because his height:weight ratio was wrong in spite of the fact that it was was pure muscle not fat.

wildswan16 Wed 03-Mar-21 17:05:18

They have to be used with common sense and caution. Rugby players, for instance, are often in the "obese" category due to their muscle mass.

Squiffy Wed 03-Mar-21 17:44:33

I came across this website, which calculates BMI in reverse!

www.countcalculate.com/diet/reverse-bmi

Redhead56 Wed 03-Mar-21 18:01:00

When I was fifty three I was 5.6 weighed 11 st. I had to go for pre op for THR. I was irritated when the nurse announced my BMI was a bit high 25.7. I was hardly active because I was waiting for my operation.
However the fact that she was a medical professional shorter than me and weighed about twenty stone positively infuriated me.

Kamiso Wed 03-Mar-21 18:05:34

I always felt the same about two of the practice nurses!

Redhead56 Wed 03-Mar-21 18:55:53

I remember thinking at the time she will be lucky to reach my age.

Elusivebutterfly Wed 03-Mar-21 19:12:52

I think for many people BMI is indication of whether we are overweight or not but we are all different. I am 22 BMI and size 14. My DGD has the same BMI as me, is 3 inches shorter and is a size 8 to 10 - she is more muscular.

Blinko Wed 03-Mar-21 19:14:43

Check out 'Smart BMI'. It gives a more sensible calculation.

Jaxjacky Wed 03-Mar-21 19:39:18

Blinko not if it’s going to shatter my illusions!

M0nica Wed 03-Mar-21 19:46:16

Totally and utterly useless. They are based on a statistic drawn up by a Belgian economist in the mid 19th century. He wanted to measure the relative level of wealth of different countries before proper financial statistics were available. The purpose of his index was to weigh samples of several hundred people in as many countries as possible and take an average for each country and the idea was that a high BMI meant you could afford to buy lost of food and get food, a low BMI and you were too poor to eat much food. I will not enter to discussion about the validity of it all, but read all about it. en.wikipedia.org/wiki/Body_mass_index

How anyone could think that a statistic based on weighing hundreds of people of all shapes and sizes and taking an average and adapting it to give a score that could then be applied to indviduals to decide whether everybody of a single height, regardless of shape and size, is overweight or not is laughable.

Ran a health and fitness show at work and we could all be assessed if we wanted. It was pre-BMI and the took folds of fat and measured them with pincers. They estimated that I was about 7-10lbs overweight. put the same height and weight figures into the BMI calculation and I am well within the safe BMI range. I just have quite a light build so BMI underestimates how overweight I actually am.

You used to get tables of height and weight ranges for small average and large build. I cannot see what was wrong with those.

Blinko Thu 04-Mar-21 19:02:03

Jaxjacky

Blinko not if it’s going to shatter my illusions!

Au contraire...

Savvy Fri 19-Mar-21 03:47:49

I never take any notice of the BMI tables, there's so much they don't take into account, especially for women. I'm 4ft 10in but I have a big bust -wear an HH bra. Muscles and bust measurements just don't come into it.

I remember when they first started to become the 'in' thing and a newsreader pointed out that according to the BMI tables, the English rugby team would be classed as obese.