Do the good old weighing scales tell the real truth?

by in Weight Loss on

It’s a great question and one we often get asked especially by new clients… The short answer is NO.

Let us explain ourselves

241/365 by Kenny Louie

"241/365" by Kenny Louie is licensed under CC BY 2.0

Scales just give an overall weight reading based on how much you weigh.. So if you are 11 stone (70kg), are you overweight? underweight? or just about right? There is no way of knowing just based on the scales reading!! 

We often hear,

"I just want to lose half a stone!!”

“Ok, but of what?”

The most common reply is “well you know... weight!?”

(In my best Mexican accent) ayiyayayaya!
**at this point the consultants head explodes**

The way we make clients look at the scales differently -

We try to make the scales more of a point of reference opposed to making them the be all and end all, the real truth lies in using the body fat callipers; 

fat calipers measuring bodyfat

We take 4 measurements using the “pinch skinfold” shown above

  • Bicep
  • Tricep
  • Suprailiac (just above hip bone)
  • Subscapular (just below shoulder blade)

Once we have added the all 4 reference points together using a mm reading we can reference it against a graph, this gives the overall body fat percentage reading. 

So if Jeff is 70kg, we have taken the body measurements and the graph shows Jeff is 18% Body fat, we can use all the information to assess the amount of lean and fat mass he has on his body.

70 (overall weight) ÷ 100 x 18 (body fat percentage) = 12.6 kg (fat mass)

12.6kg (fat mass) - 70 (overall weight) = 57.4 kg (lean mass)

Now we have managed to determine the amount of body fat Jeff is carrying - 12.6 kg (18%)

Most men like to be under the 10%, sometimes referred to as the 10% club, for Jeff to do this he would have to make a body fat reduction of 8% (assuming his lean mass didn’t increase whilst making the reduction.) - Lets say this is Jeff’s goal!

70 (overall weight) ÷ 100 x 8 (the GOAL) = 5.6 kg

For Jeff to get under the magic number of 10% he would have to loose a total fat mass of 5.6kg (12.34 lbs) - This doesn’t mean 12.34 lbs on the bathroom scales this means 12.34 lbs of pure body fat. 

A FALSE reading

Untitled by Daniel Oines, on Flickr

This work is a derivative of Untitled by Daniel Oines is licensed under CC BY 2.0

Jeff's been on top with his Nutrition and we are going to measure his body fat again, its been 2 weeks so we are expecting a RESULT.

He’s 69.3kg on the scales… OH NO - not quiet as good as we were thinking!? Hold on... 

We have done the Skinfold measurement he’s 15.8% Body fat.. RESULT

69.3kg (overall weight) ÷ 100 x 15.8 (body fat) = 10.94 kg

69.3 kg - 10.94kg (fat mass) = 58.36 kg (lean mass)

So lets compare the measurements between the 1st and 2nd:

  • Was 18% body fat now 15.8% - 2.2% reduction
  • Fat mass 12.6kg now 10.94kg - 1.66kg of PURE fat loss
  • An increase in lean mass it was 57.4kg now its 58.36kg - a total increase in lean of 0.96kg

Overall Jeff has had an awesome result when the measurements have been broken down into body fat percentage, fat mass and lean mass. However, if Jeff had of just took the scale's reading he would be rather disappointed. Why? because its only 0.7kg! He’d actually done 1.66 kg of FAT.

So what’s our beef with the Bathroom Scales?

We have given the bathroom scales a bit of a grilling in this blog, however, in some cases they deserve it and in others they do not.

Here is why they do -

  • They offer no anatomical facts other than the overall weight measurement.
  • If you were to eat “no carbs” you would deplete your glycogen stores and this would in turn make you a lot lighter on the scales.
  • If you were to drink a lot of water or no water this would have a increased or decreased measurement on the scales.

Physiological Association

/doh by hobvias sudoneighm, on Flickr

/doh by Hobvias Sudoneighm is licensed under CC BY 2.0

I once heard a woman say “I’m not eating anything today i’m being weighed tonight”


If you are ever at a point in your life were your scared to eat food because you're being measured on scales PLEASE either 

So lets wrap it up….

If you weigh yourself on a regular basis or maybe you know, or work with a "scales addict" and the measurement has decreased by 2 lbs one week, good for you or them. But please always bear in mind the magic question…?


Water? Glycogen? “Weight”? Fat? Hair Cut? Just been the loo?

If you want to know your body fat percentage, please give us a call we’d happily measure your body fat, and we don’t charge £3 for the privilege either

TLG Team.

  1. Throw them in the bin
  2. or
  3. Do NOT attend to be measured.
Latest update: 13/08/2016

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