# What is your BMI?

## Recommended Posts

I have recently been trying to lose a little weight and generally become a little healthier. I have cut down my food intake, am being very careful with the sort of things I eat (lots of fruit and veg, very little fat etc) and I am going to the gym regularly.

I started off at 98kg and after a little under a month I am down to 92kg. Initially my target weight was 85kg, which I though seemed pretty reasonable.

Anyway, my wife suggested that I should check my Body Mass Index to find my ideal weight. This is calculated according to:

$BMI = \frac{W}{h^2}$

where $W$ is your weight and $h$ is your height, both in SI units (kilograms and metres respectively). A normal BMI is 18.5 - 25 kg/m2. (I will supress units from now on)

So I was $\frac{98}{1.82^2} = 29.6$ and I am now $\frac{92}{1.82^2} = 27.8$, so I still have a long way to go.

The thing which suprised me was my required target weight in order to not be classed as overweight. In other words, if I want a BMI of 25, I need to acheive a weight of $25 \times 1.82^2 = 82.8kg$.

So if I don't want to be overweight any more I have to lose over 9kg more! And if I want to be in the middle of the normal band (BMI of 21.75) I need to lose another 20kg!

I was wondering how realistic these sort of numbers are. What is your BMI, and do you have any tips for reducing my weight?

• Replies 51
• Created

#### Popular Days

My BMI = 18.8. Diet and exercise, my friend.

##### Share on other sites

I have recently been trying to lose a little weight and generally become a little healthier. I have cut down my food intake, am being very careful with the sort of things I eat (lots of fruit and veg, very little fat etc) and I am going to the gym regularly.

I started off at 98kg and after a little under a month I am down to 92kg. Initially my target weight was 85kg, which I though seemed pretty reasonable.

Anyway, my wife suggested that I should check my Body Mass Index to find my ideal weight. This is calculated according to:

$BMI = \frac{W}{h^2}$

where $W$ is your weight and $h$ is your height, both in SI units (kilograms and metres respectively). A normal BMI is 18.5 - 25 kg/m2. (I will supress units from now on)

So I was $\frac{98}{1.82^2} = 29.6$ and I am now $\frac{92}{1.82^2} = 27.8$, so I still have a long way to go.

The thing which suprised me was my required target weight in order to not be classed as overweight. In other words, if I want a BMI of 25, I need to acheive a weight of $25 \times 1.82^2 = 82.8kg$.

So if I don't want to be overweight any more I have to lose over 9kg more! And if I want to be in the middle of the normal band (BMI of 21.75) I need to lose another 20kg!

I was wondering how realistic these sort of numbers are. What is your BMI, and do you have any tips for reducing my weight?

BMI is not a bad way of deciding whether you are overweight, but calipers to measure body fat or even a mirror are much better.

Interesting that it uses height squared rather than cubed.

##### Share on other sites

20.38... nearly perfect

##### Share on other sites

It was my understanding that BMI is seriously flawed, mostly because it doesn't take into account percentage body fat. A professional athlete and a big fat guy can have the same weight and height, but one gets the weight from muscle and the other fat.

As for your actual questions, I'm right about in the middle of "normal" according to BMI (don't know my exact weight), and I don't have any suggestions beyond the obvious - portion control, take the stairs, etc.

##### Share on other sites

It was my understanding that BMI is seriously flawed, mostly because it doesn't take into account percentage body fat. A professional athlete and a big fat guy can have the same weight and height, but one gets the weight from muscle and the other fat.

As for your actual questions, I'm right about in the middle of "normal" according to BMI (don't know my exact weight), and I don't have any suggestions beyond the obvious - portion control, take the stairs, etc.

I think that is the key. Lot's of kindling (small meals) no heavy logs, and avoid your "trigger" foods.

Keep the fat fires burning.

Lifting weights, preferably high reps, or a good all around exercise program will keep the metabolism high as well. The extra calories burned during the actual workout are usually not that high, but will help you lose throughout the day.

##### Share on other sites

I have a scale that tells my body fat percentages.

Right now I am at 24.7 percent.

I weight 195 and 6'0"

BMI with that would be: 26.4

It doesn't take into count muscle mass.

I am hoping to get down to 18 - 20 BFP.

while retaining most of my muscles. I work hard for them damn it. If you can afford a gym membership I would suggest getting a trainer to get you started on weight-lifting, Even though I am not skinny, I can preform as well or more than most fit people who are without the same muscles. Especially as you get older and muscle deterioration becomes more common it will help out a lot. (wiki says I am in normal BF range, but definitely not athlete range lol)

What is good too is martial arts....you should check that out severian, even like fencing or something....any activity that you can enjoy and isn't too stressing that will promote activity without it getting boring. I run stairs pretty much every day, and that gets quite repetitive. you need to do something that you constantly do, because it takes a long time

I use to be 235 with no nearly the same muscles mass, It was pretty bad, It's been 2 years and I am still working on it. I noticed too exercise calm the hunger for me. Not every has this but it would be interesting to see for yourself. Walk up some really long stairs and back down, and see if it affects you in the same way....it might work. You can go for a walk if you feel cravings.

##### Share on other sites

I'm 6'2", about 180, so ~23 is my BMI.

(1.9m and 82.1kg, so 22.7 BMI).

The short answer? If you want to lose mass, burn off more energy than you ingest and keep doing so until you find the equilibrium you want.

##### Share on other sites

I am already a member of a gym and my workout is first on one of these cardio machines that are a cross between a treadmill and steps, and then strength building on weight machines. This is about an hour, 4 times a week.

I think I am actually fairly fit and fairly strong. I notice that I am lifting weights which are quite a bit heavier than most of the other people in the gym and they don't give me any problems. I can also run up stairs pretty well. Both my home and work are at the top of 5 flights and I can run up them two at a time and not be out of breath at the top.

I actually have quite a large frame and I am already fairly well muscled (my trainer commented on this when I started), so I am slightly suspicious that my BMI is not a very good representation of how overweight I am. I also don't feel fat - I don't have a 'belly' and apart from my 'love handles' at the side of my waist I can't pinch much excess fat.

I have been thinking about taking up a martial art. I would really like to be able to defend myself, so the sort of thing where I could learn to disarm someone or take on multiple opponents would be nice. Since I live in Glasgow, it might come in handy to be able to seriously intimidate someone without killing them. Any suggestions? I used to fence when I was younger.

Metabolically, I think I am a bit weird. I don't seem to get hungry at all. I have in the past, when my wife was away, simply forgotten to eat because I have no hunger pangs. I eventually feel light headed and then realise why. So for me eating is more of a psychological habit, and something I do socially.

I am trying to eat small meals regularly, and I think I am doing fairly well, since I never feel the need to snack. In fact, I haven't had any chocolate, or candy or anything else like that for over a month now. I have been eating a lot of fruit though, which is maybe not so good since they can have a lot of sugar in them. I need to get better at eating breakfast. In the past, I used to skip breakfast quite often, but now, through the week, I am trying to have a bowl of cereal and a glass of orange juice, and at weekends some scrambled eggs and smoked salmon. I have given up coffee and am drinking mainly green tea. I have also given up alcohol except for the odd glass of red wine.

##### Share on other sites

It sounds like you're already doing everything right, Severian. You have a solid understanding of what is important, and you're doing it. Just stick with it, and you should be fine.

You mentioned martial arts. I'm somewhat biased, but I always loved the workout I got with kung fu. Lots of cardio and strength training, and I was in the best shape of my life. I coupled it with Tai Chi, which helped me to develop the smaller muscles involved in balance, and it strangely added a tremendous amount of power to my strikes (even more so than weight training). You'll likely want something with more cadio than grappling if you're doing it primarily for fitness reasons.

Anyway, have fun with it, and do what you can to work out with people whose company you enjoy. If you enjoy what you're doing, it's much more likely to become a lifestyle than just get left behind as a temporary fad/faze. Cheers.

##### Share on other sites

Hmm, I got a BMI of 20, last time I checked the body fat was around 17 %.

However even now I do not really exercise (unless yelling at experiment counts). I do cook what could be considered healthy for the most part, but I do not really follow a diet. In the end however, I won't be able to lift as much as those that train (obviously). On the positive side is that I can use up the time that I would needed for workout to do stuff and be productive, like.... posting on this forum.... darn.

Metabolically, I think I am a bit weird. I don't seem to get hungry at all. I have in the past, when my wife was away, simply forgotten to eat because I have no hunger pangs. I eventually feel light headed and then realise why. So for me eating is more of a psychological habit, and something I do socially.

I have/had that, too. Coupled with stress I often forgot to eat and actually ignored dizzyness during work. Couple that with long working ours and you got a very bad lifestyle, I can tell you.

##### Share on other sites

I am already a member of a gym and my workout is first on one of these cardio machines that are a cross between a treadmill and steps, and then strength building on weight machines. This is about an hour, 4 times a week.

I think I am actually fairly fit and fairly strong. I notice that I am lifting weights which are quite a bit heavier than most of the other people in the gym and they don't give me any problems. I can also run up stairs pretty well. Both my home and work are at the top of 5 flights and I can run up them two at a time and not be out of breath at the top.

I actually have quite a large frame and I am already fairly well muscled (my trainer commented on this when I started), so I am slightly suspicious that my BMI is not a very good representation of how overweight I am. I also don't feel fat - I don't have a 'belly' and apart from my 'love handles' at the side of my waist I can't pinch much excess fat.

I have been thinking about taking up a martial art. I would really like to be able to defend myself, so the sort of thing where I could learn to disarm someone or take on multiple opponents would be nice. Since I live in Glasgow, it might come in handy to be able to seriously intimidate someone without killing them. Any suggestions? I used to fence when I was younger.

Metabolically, I think I am a bit weird. I don't seem to get hungry at all. I have in the past, when my wife was away, simply forgotten to eat because I have no hunger pangs. I eventually feel light headed and then realise why. So for me eating is more of a psychological habit, and something I do socially.

I am trying to eat small meals regularly, and I think I am doing fairly well, since I never feel the need to snack. In fact, I haven't had any chocolate, or candy or anything else like that for over a month now. I have been eating a lot of fruit though, which is maybe not so good since they can have a lot of sugar in them. I need to get better at eating breakfast. In the past, I used to skip breakfast quite often, but now, through the week, I am trying to have a bowl of cereal and a glass of orange juice, and at weekends some scrambled eggs and smoked salmon. I have given up coffee and am drinking mainly green tea. I have also given up alcohol except for the odd glass of red wine.

I think it is pretty clear from your description that you are not overweight. The BMI as an indicator of being overweight has failed in your case. Simply looking in the mirror is much more accurate.

##### Share on other sites

Nice Severian, have you asked the trainer at the gym about it. To me you just seem like one of those naturally big guys. I know a lot of Ukrainian people that are like that. Big and strong. If you don't have a belly, than I don't think you have to worry much. I have a bit of belly with some ab muscles showing and my BF is in healthy range. It might be just your size....it's based on average right. The trainer might have a different way to calculate it. If what you are saying is true it might be dangerous for you to go that low. To have that BMI seems seriously misleading...I would see if the gym has a body fat analyzer and see if you can get someone to check it for you. I serious think you would be in like the 18 - 22 bf range. Damn it! not only do I have to catch back to where I was and my little brother, now severian too! The pressure is intense...I am going to have to quit smoking

MY suggestion for martial arts:

For purely self defense, commando krav maga. My older brother takes it and we both love martial arts he has shown me some aspects to it and it's pretty interesting, I want to take it one day too. It focuses more on surivival. Krav Maga is pretty much the same but commando adds judo and jujitsu techniques, it has mostly open hand or palm strikes to reduce injury. Knife and gun disarms. Basically it's "I don't want to fight you, I don't want to fight you"...*BAM* person is down and you get away.

If you are a big guy like you said Judo might be interesting, If you get good at it you can use aspects to defend yourself but most people don't recommend grappling in a street fight. I wouldn't but you would be more comfortable in a situation where I guys trying to grapple you. Everyone says mauy thai, I am not a big fan of it. Jujitsu is interesting,,,,I want to give that a shot, it's grappling as well but more focused on the ground, defending from the back and on top and using technique, usually frustrating at first and probably more so for bigger guys, boxing would probably be the best. If you did boxing and judo, I think you would be ok.

Other than that anything really. Karate, Kung Fu, Tae Kwon Do (the kicking might be a bit much), wrestling, See if there is any club in the area that offer a free lesson and try it out.

To me defending your self and being a good fighter are more along the lines of the individual. I will never say that one style is better than the other. In the end the best defense is not fighting or avoiding since anything can happen.

I am slightly obsessed though, you might not want to take my advice.

lastly I will leave you with some humour from my fellow dutch man, EX UFC champion Bas Rutten.with self defense

D3K-mrlYG7Y

I am going to stop I could go on forever. I love the fact that there are other people here that are into martial arts, I recommend it to anyone.

Edited by GutZ
##### Share on other sites

Martial arts wise, I am probably restricted to the classes I can get in the gym. I will have to find out what they do. I know they do karate and judo, but I am not sure what else.

I mainly want something where I can subdue rather than hurt. I have only ever been in one fight as an adult and I just decked him. He went down and didn't get up and I was terrified I had killed him.

##### Share on other sites

Just btw. and off-topic using the word kung fu as if it was a martial arts style kind of annoys me (a pet peeve of mine). What precisely is meant (e.g. I used to learn hsing-i chuan)? For a general term "Chinese martial arts" is actually more accurate than saying kung fu (which basically means something like "ability or technique" in a more general sense). Of course one could argue that this term has been westernized so much that it has changed its meaning in the western worlds, but it still is wrong.

OK that is the rant for the day. Thanks for your patience.

Edited by CharonY
##### Share on other sites

while I agree with CharonY, the Chinese (and subsequently, the Japanese) still make a dang good art style that's good for stress release, exercise and self defense.

Personally I favor styles that use precision to hit pressure points..but that video was hilarious.

BMI is ... let's just say I'm probably the fat one of the forum. I think my % ~31 or so, but I've gotten kind of bored of being fat, and am now on my way down.

##### Share on other sites

The BMI is a complete load for a wide variety of reasons.

Firstly, it's fundamentally flawed - weight goes up to the cube, not the square, and this holds true both within species and on shrew-to-elephant lines.

Secondly, as pointed out, it fails to take into account varying body composition. Fat vs muscle is often pointed out, but bone mass can be very significant, especially if you've previously done a lot of high-impact stuff.

Finally, and most importantly, it's entirely arbitrary and socially defined - the BMI cutoffs were lowered in 1998, manufacturing an "obesity epidemic" out of thin air.

IMHO, its worthless, both for individuals and as a study tool. It's for lazy researchers who can't get off their ass and make real measurements.

Now, as for your health, the best bet is to just go to the doctor and ask for either a physical, or just a blood test + pulse + blood pressure. (Keep in mind that if you're a big guy, especially if you're tall, your blood pressure will naturally be a bit higher just to push the blood around). That'll give you *accurate* information about your risks and such.

Also, don't get your expectations up too high. Remember that it's not as simple as calories-in - calories-out; the body is incredibly complex, with numerous feedback mechanisms regulating basal metabolic rate, digestive efficiency, nutrient uptake, nutrient metabolism, etc.

The idea that everyone can be thin if they work hard enough is, quite simply, wrong. What's more important is being *healthy* - if you have a bit of extra weight, but you have good pulse, blood pressure, cholesterol, etc., then there's nothing to really worry about.

##### Share on other sites

"I do not think that measuring BMI is that easy.... I have read of much more precise method..."

What is it?

"It's for lazy researchers who can't get off their ass and make real measurements."

You need to make two measurements to calculate it. In terms of identifying people who are obese (by whatever standard) it's a lot better than either of those measurements on their own.

It fails for some people- so what?

Of course you need to look at individuals.

It's still fair to say that if your BMI falls in the "normal" range, then you don't need to worry about your weight and you can concentrate your efforts elewhere- like stopping smoking, drinking less or whatever.

it was never designed as the be all and end all of classification of human body shapes, just a simple tool to see who needs to watch their weight one way or the other.

Of course, you can just look in the mirror but what you see depends on your personal bias and what society expects.

Would these models get work in today's world?

http://www.abcgallery.com/R/rubens/rubens21.html

At least the BMI is objective. You can plot out mortallity rates for different BIMs and so on.

##### Share on other sites

"I do not think that measuring BMI is that easy.... I have read of much more precise method..."

What is it?

Pretty much *anything* gives better results than the BMI - skin-fold calipers, densiometry, bioelectrical impedance, all superior. Of course, nothing beats ultrasound, CAT scans, and MRIs, but those are quite expensive.

You need to make two measurements to calculate it. In terms of identifying people who are obese (by whatever standard) it's a lot better than either of those measurements on their own.

And it's vastly inferior to the half-dozen methods listed above. It gets used because it's easier to just download a database of patient records, do some quick math, and then go data-mining than to actually do things properly with superior methods (and, most especially, with multiple methods to check the accuracy of one against the other).

it was never designed as the be all and end all of classification of human body shapes, just a simple tool to see who needs to watch their weight one way or the other.

And it fails, miserably. People who are long-term anorexics have been told their weight is OK or even a bit high based on the BMI, while perfectly healthy people have needlessly had invasive surgery to fix a body that didn't fit in the narrow little numerical range. Take a look at how utterly the BMI fails to reflect reality.

And remember, aside from the intrinsic failures of the BMI as a method, the cutoffs are defined in entirely arbitrary ways, and have been repeatedly "revised" in order to manufacture an imaginary health crisis out of thin air.

I thought the point of science wasn't to half-ass it? The BMI is like trying to measure the speed of light using two guys in a hallway with stopwatches. In light of all the other potential methods, why continue using the worst?

At least the BMI is objective. You can plot out mortallity rates for different BIMs and so on

Yep, and the mortality is consistently lowest at the BMI category "overweight", which should tell us something right away. Except nobody wants to face up to it.

##### Share on other sites

So what other way can I assess my weight by myself, without consulting a doctor?

##### Share on other sites

I weigh 160lbs or roughly 73kg, I am 5' 10" and have a BMI of roughly 25.15. I wear a size 8/9 or 28! I'm not considered overweight by anyone I know. In fact most people say that I'm pretty slim. Being that I have a well defined physic I am in no way skinny. I'm not muscally either. Regardless I do a lot of exercising, I can run for an hour at 10 to 11kph or like 6.5mph. Most men I date are well over 100kg @ roughly 2meters. They also are not fat. I don't understand this sudden craze to be small I think it sucks................ I think it's a ploy to make a weaker populace allowing for greater manageability.

Severian almost all gyms employ kinesiologist who are well trained in taking measurements of individuals and their body fat percentage. They often will do it for free the first time.......a complete physical! Even if they don't they probably won't charge you more than \$30.

Don't get small get cut, yo!

Edited by buttacup
##### Share on other sites

I do not think that measuring BMI is that easy.... I have read of much more precise method...

It is actually very easy. All you need is weight and height. Everything else is ignored, which is why it can be a terribly inaccurate indicator for individuals.

##### Share on other sites

So what other way can I assess my weight by myself, without consulting a doctor?

You might consider checking your waist-to-hip ratio if you haven't already. One of my old professors, Dev Singh, came up with the idea, and it's a pretty reliable measure of attractiveness and health.

http://en.wikipedia.org/wiki/Waist-hip_ratio

As a male, you should strive for a ~0.9 (incidentally, this is the exact ratio of Michaelangelo's David IIRC). Females would want to be around 0.7.

##### Share on other sites

So what other way can I assess my weight by myself, without consulting a doctor?

Some home scales have bio-impedance functions (though I cannot attest to their accuracy). If you have access to your own pool, you could also weigh yourself in the pool to get an idea of your overall density (fat is less dense than fresh water, while muscle, bone, and just about everything else is more dense).

Honestly, though, a doctor's visit may well be worth it. I just had one for bloodwork because my wife was worried about my cholesterol (on account of my belief that bacon is a food group), and I found out I actually have low cholesterol, so no diet for me.

After all, you need initial data, right? Plus, IME, it's not very expensive for most of the important stuff.

##### Share on other sites

... (on account of my belief that bacon is a food group)...

That's not a belief, that's a fact.

## Create an account or sign in to comment

You need to be a member in order to leave a comment

## Create an account

Sign up for a new account in our community. It's easy!

Register a new account