How Much Should You Weigh?

How Much Should You Weigh?
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There’s a huge amount of attention given to the health issues associated with obesity. However, we’re big believers in the saying “coincidence is not causality”. Visit any fitness-related website and you’ll see that it’s not enough to be thin – you also need to be fit. Nonetheless, the fact remains that body weight and composition remain significant indicators for health issues such as heart disease and diabetes. So, how do we know what our optimal body weight should be?

Until recently, Body Mass Index, or BMI, was considered the most accurate gauge of the ideal bodyweight. BMI is a ratio of your weight and height. It’s calculated by dividing your weight in kilograms by your height in metres squared.

In my case, BMI = 85/1.78*1.78 = 26.8.

A BMI of under 18.5 is considered underweight. A BMI between 18.5 and 25 is considered ideal with 25-30 considered overweight. If it’s over 30 the charts say you’re obese.

The trouble with BMI is that a muscular person will come in with a high BMI as they’ll be relatively heavy.

My doctor takes a far simpler approach. He likes to use waist measurements. They’re simple although they rely on a correlation that suggests a measurement of more that 94cm for men or 80cm for women are indicators of increased risk for chronic disease. Add another 8cm to those and the risks jump substantially.

The assumption is that increased waist measurement s come from excess fat stored around the midriff suggesting that you’re overweight.

Another measurement technique takes into account your frame size. Start by calculating your baseline weight. For men it’s 50kg for the first 150cm of height plus and kilo for each cm of height. For women, start with 45kg.

You then need to determine your frame size. Measure your wrist. For mean, a circumference of more than 19cm is considered large. If it’s under 16.5cm then you have a small frame. In between is medium.

For women it’s a little more complex as it’s height related.

Under 157cm tall

Under 14cm – small
Between 14.0 and 14.6 – medium
Over 14.6 – large

Between 157 and 165cm tall

Under 15.2cm – small
Between 15.2 and 15.9 – medium
Over 15.9 – large

Over 165cm tall

Under 15.9cm – small
Between 15.9 and 16.5 – medium
Over 16.5 – large

All that’s left is the final step. If you have a small frame, subtract 4.5kg from your baseline weight for your ideal weight. If you have large frame you can add 4.5kg. A medium frame means your baseline weight is your ideal weight.

So, in my case, at 178cm tall, my base like weight is 50kg + 28kg = 78kg. My wrist has a circumference of 19cm so my ideal weight, based on this system is 82.5kg.

What’s interesting with all of these is that, at least in my case, there’s not a huge difference in what my ideal weight ought to be. Personally, I think the real test is in maintaining a healthy lifestyle with a balanced diet and regular exercise. If you do that, your weight should look after itself.


  • Firstly, where you say weight you should say mass. As soon as I travel to the moon, I shouldn’t be considered grossly underweight.

    Secondly, the Ponderal Index works better for people outside of average height. I cubes the height rather than squares it and creates a better relation.

    • Its called the world wide web – Assuming people reading it are based the majority of the time on Earth. check out the Moon wide web… its basically the same but refers to weight as Mass

    • I’m sorry but is this comment really necessary? There are very few people who go to the moon and none of those people have weight issues because NASA regulates all that sort of stuff!!

  • I appreciate the collation of these information, but any article with zero citation substantially drops in credibility. Would it be possible to at least link it out wikipedia style [1]?

  • “Until recently, Body Mass Index, or BMI, was considered the most accurate gauge of the ideal bodyweight. ”

    – only by lifestyle editors.

  • BMI was developed for use on population studies, it was specifically mentioned it was never intended to be applied to individuals but at some point an idiot did it and it stuck.

  • BMI is an excellent measure of bodyweight when used in population studies, using it on an individual is not as good.

    • Yeah the BMI gets it from both ends.

      It’s just a methodological tool with a specific use. That specific use means that hardly any of us should be using it.

    • It’s weird isn’t it. I think you are right but logically it doesn’t make any sense, if something is not accurate for one person, using it for many can only be inaccurate.

  • on the BMI scale, Lebron James is morbidly obese. It’s not accurate. The only real way to measure is body fat percentage.

  • Numbers are meaningless really, you can usually tell just by looking at someone where they’re at. That and the fact that muscle weighs more than fat and then there’s different bone density etc. Everybody’s different so there’s no accurate way for everyone.

  • I’m not sure that I under stand the last set of measurments- it still doesn’t take muscle vs fat into account. And if you are on the chubby side wouldn’t it incorrectly read as large-framed even if that’s not actually the case?

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