BMI Calculator

Calculate your Body Mass Index to determine if you're in a healthy weight range

BMI is a simple, universal measure of body fat that can be used to determine whether or not your weight is healthy. BMI is derived by comparing your height to your weight. It can be used by men and women of all ages.
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I am an older male; i am 5ft 7" tall and weigh 10 stone currently. I have recently been told by a practice nurse that i am underweight. My wife thinks the same thing. My BMI says i am 21.75 - considered to be in the healthy weight range. What should i believe?
Posted: 28/12/2010 at 13:32

If your BMI is 21.75, you are not underweight.  What makes them think that you are?

Posted: 28/12/2010 at 18:05

No idea what an older male is but I'm pushing the higher end of 30 and am.
170cm (7ft-7) and weigh 62.86 kg (9st 9lb)
I have also put on weight since running as I have built some muscle and am currently the heaviest I have ever been

Going by me your a bloody porker  but im happy I do not have the same practice nurse as you.

Also worth noting that BMI is seriously flawed as its a 19th century calculation which squares the hight by the weight of a population. BMI also ignores waist size, which is a clear indicator of obesity level. BMI makes no allowance for the relative proportions of bone, muscle and fat in the body. But bone is denser than muscle and twice as dense as fat, so a person with strong bones, good muscle tone and low fat will have a high BMI because of this it is not uncommon for world class athletes to find themselves classified as overweight or even obese according to BMI.

Posted: 28/12/2010 at 20:09

Squeakz wrote (see)

No idea what an older male is but I'm pushing the higher end of 30 and am.
170cm (7ft-7) and weigh 62.86 kg (9st 9lb)

You're a bit light for someone 7 1/2 foot tall

Posted: 28/12/2010 at 20:19

ROFL fair point Rob never noticed that ohh the joys of typo's (perhaps ive grown a few feet although last time I checked I was 5ft 7)
Posted: 30/12/2010 at 09:00

I agree with Squeakz, BMI is a realitively antiquated, none scientific way of measuring body index. It is crude in the extrememe. I have never made the average even when I had a body fat index of less than 9%. It doesn't factor in bone density or muscular physique. You'd be better off having your body fat measure by a qualified sports instructor. I'm 161cm tall with a bmi of 27 so technically I'm o

Posted: 21/01/2015 at 23:55

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