Reduce or increase your BMI instantly.

But PLEASE don't forget that whether the new calculations make it higher or lower, you're EXACTLY the same person, just as healthy (or unhealthy) as you were before you read this thread.

That's what you get when a mathematician makes an assumption about human biology and the variation within the human species, that is not borne out by reality at all.

He has assumed that tall people are scaled up versions of short people.... *they are not*

Measurable human variation says otherwise:

- many short people are short because their limbs are shorter than average, while their torsos are average size or even larger than average

- torso size can vary in breadth and depth, not just height. Short people can have broad shoulders and large rib cages than average, and tall people can have more slender shoulders, ribs and pelvises than average.

- people in dry, tropical climates tend to be tall and small framed, while people from colder climates tend to be shorter and larger framed, because of how this affects surface area to volume ratio, and therefore the rate of heat loss from the body. This is Allen's law, in case anyone wants to look it up, and it's true in non-human animals too. There are many other factors that affect human variation in height and frame size, but the fact that this has been observed repeatedly in humans, including strong evidence of natural selection in favour of these traits in the relevent climates .....it just shows how wrong the assumption that tall people are scaled up versions of short people is. It's actually more likely to be the opposite, on the whole, but of course there are people with all different relative limb lengths and all different widths of shoulders and rib cages at every height. *frame size and torso size do not correlate with height*

I think it'd be better to let biologists and anthropologists make accurate statements about human variation based on actual data collected from actual humans............. and let the mathemeticians stick to maths,or at the very least, base their mathematical models on actual data from actual humans, not from blind, untested assumptions about human variation.

BMI is a load of poo anyway, body fat percentage is better. The original BMI was bad enough, this guy just made it all the more inaccurate for short, large framed people (being told they're obese when they're not), and tall small framed people (being told they're healthy when they're carrying way too much fat). Which is going to be a huge sector of the human race. It's even less accurate than the original BMI.

No need to ask which way your calculation went then! Do you suspect that there may be a conspiracy and that the oxford professor responsible is really tall?

I didn't do the calculation at all, because I can tell from the off that it's a crock of s****

actually I'm proud of the fact that I have a high lean body mass for my height. My body fat percentage is in the healthy range and my lean body mass is in the healthy BMI range (for bodyweight) for my height. My lean body mass is somewhere between 102 and 107lb (depending on how you measure body fat percentage) and the BMI healthy weight range for my height is 100-132lb - in other words, my lean body mass is greater than the entire weight of some healthy women of my height .... this new adjusted BMI range is actually better for me, because my lean body mass will be closer to the middle of that range, not right at the low end as it is with standard BMI. So really, I should actually like this "new" BMI range, if it's about personal goals and personal pride. Not everyone has the goal to have as low a BMI as possible. Personally, I'm trying to be as heavy as possible while still having a mid of the healthy range body fat percentage, and still fitting into the same size clothes as when I was lighter, because my main goal is to be as strong as possible, and more lean mass = stronger.

However it's not about personal pride, it's about people's health.

There's a huge potential negative health impact telling people they're overweight/obese when they're not. If your body fat percentage is in the healthy range, then you're not carrying too much fat, you don't need to lose weight, and there are quite serious health risks for people who try to lose too much weight, because body fat percentages below the healthy range are associated with reproductive health issues including temporary infertility, and also a greater risk of osteoporosis. Then there's all the health risks from losing lean body mass, also including loss of bone density, and just the general fact that it makes you a lot weaker, rather than stronger, and slows your metabolism. Then there's eating disorders....

And it's not just health risks for people being told they're overweight when they're not......... there are actually more people who are told by BMI that their weight is in the healthy range when their body fat percentage is in the obese range. They are at all the same health risks as anyone else with an obese body fat percentage, but they also have the risks that come with being underweight, because in these people they have two problems: 1. underweight lean body mass, and 2. carrying too much body fat. So they're actually less healthy than someone who has a decent amount of lean body mass and the same body fat percentage. People get like this by being sedentary, skipping meals (whether deliberately to lose weight or because they're too busy to eat or whatever) and eating a poor diet generally. They may be envied by some "how can he eat all that junk and still stay thin" but a BMI in the healthy range does not mean you're healthy. And a BMI in the overweight range (or even in some cases the low end of the obese range) does not necessarily mean you're carrying too much fat.

All in all, BMI should be scrapped because it can be very misleading, dangerously so for some people, and replaced by body fat percentage instead, so all the "how come he eats so much junk and never exercises and is still thin?" people can come to realise just how unhealthy their body composition is, and athletes and large framed people who have high lean body mass for their height, can stop being told that they're fat when they're not.

Also, all of what I said about human variation can be verified in anthropology textbooks, or any other field of biology that deals with variation in the human population, rather than averages.