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body fat %

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decided to do an 'official' weigh in (wasn't sure i trusted my home scales) on scales in the pharmacy, with body fat measurement via gripping the handles.

Good news - I've lost 2.4kg since the last time I was on those scales (6 weeks ago)
Bad news - I've apparently gained 4.4kg of fat!

My weight has gone from 61.2 to 58.8kg, but body fat from 21.4% (in the excellent category for a 35yr old female) to 29.8% (average).

My question is - do I just assumed that the accuracy of this machine's body fat % calculations is awful and ignore completely - or is it possible that I have lost weight whilst gaining fat? I'm 1m66 and fairly muscular; from pictures I've seen of bodies at different % fat I'd probably estimate I'm in the 20-25% range - I was hoping to edge to the lower end of that bracket or possibly below - so was a bit annoyed to be told I'd gone up!

I'm thinking I just ignore it (and not waste the extra 20p to be told nonsense in future!) but opinions welcomed.

Replies

  • JenAndSome
    JenAndSome Posts: 1,893 Member
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    What kind of machine are you using to measure body fat? Many of them are wholly inaccurate and mostly measure level of hydration in the body. Are you also taking measurements with a measuring tape? What kind of exercise, if any, are you doing?
  • Muscleflex79
    Muscleflex79 Posts: 1,917 Member
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    yes - awful measure - completely ignore it!
  • cityruss
    cityruss Posts: 2,493 Member
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    Stick to your own scales only, observe trends. Who cares if your scales are a few lbs out, the number displayed matters little within the margins of error consumer products like home scales give, it really isn't the end of the world if your scales weigh you a few lbs heavier, as long as that number is either maintaining or going down.

    Ignore bodyfat readings.
  • 3dogsrunning
    3dogsrunning Posts: 27,167 Member
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    I went away for the weekend and almost doubled my body fat according to my scale.
    I suspect extra eating, water retention due to flying/sodium/alcohol played a role.

    My point - a lot of factors affect the scale. I'd chalk it up to degree of error.
  • VisofSer
    VisofSer Posts: 130 Member
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    These BF% measures are electric impedance measurements which are done by passing a small current through your body and measures the resistance to the flow of electricity from one sensor(handle in this case) to the other. These are not very accurate due to how strongly your current water and mineral content affects the results.

    The two best ways to get an accurate measure of body fat is a DEXA scan, or calipers. Tape measure can be used as well but it is simply not as accurate. Of course ultimately, all of these are estimates as the only perfect way to measure body fat would be to be dissected. As a rule, unless you are having a DEXA scan done regularly, the trend of your measurements is more important than the precise numbers due to how easy it is to have errors due to body and measurement irregularity.

    In short, use calipers and a calculator such as this for the most accurate at home BF measurement. They are best done with another person to aid. Even with calipers, the trend trumps the numbers.
  • DarrenKH
    DarrenKH Posts: 21 Member
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    Thanks for sharing, and the other contributions, I just started using a Taylor scale with body fat measures so will be monitoring. Maybe try another scale, perhaps the one you use has a problem? I am reluctant to throw out the whole idea of it. And you dont mention it, but I assume you have checked that you are not in fact losing muscle, do you exercise much, and what kind? I am mindful of this because I have no problem running but am trying to incorporate more strengthening as well.
  • soapsandropes
    soapsandropes Posts: 269 Member
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    Ignore the scale BF%, the results are influenced by your hydration state and a bunch of other stuff.
  • norcogrrl
    norcogrrl Posts: 129 Member
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    I use the Taylor Bluetooth Body Fat Smart Scale, and I compare my results to both the U.S. Navy Circumference Method and the Covert Bailey "Fit or Fat" method. Based on photographs of people at the body fat percentages I arrive at, I look more like the Covert Bailey results.

    My scale is always within 1% of the Covert Bailey "Fit or Fat" method, and the results are very consistent.
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    edited December 2015
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    My question is - do I just assumed that the accuracy of this machine's body fat % calculations is awful and ignore completely - or is it possible that I have lost weight whilst gaining fat?

    Extremely unlikely that you have actually gained fat while losing weight. Those scales aren't particularly accurate and they are useful only as a general trend -- if you weigh yourself often you should see the number generally give consistent results on average, but it will bounce around and be influenced by all kinds of things and is completely useless if you don't weigh under precisely the same conditions or regularly enough to see the pattern and recognize the outliers. I would ignore it and go by measurements and appearance if you want something besides weight (which is a good idea).
  • ninerbuff
    ninerbuff Posts: 48,747 Member
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    Bioimpedance in one of the WORST ways to determine body fat %. Just how hydrated you are will affect the reading itself.

    A.C.E. Certified Personal and Group Fitness Trainer
    IDEA Fitness member
    Kickboxing Certified Instructor
    Been in fitness for 30 years and have studied kinesiology and nutrition

    9285851.png
  • Sued0nim
    Sued0nim Posts: 17,456 Member
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    DarrenKH wrote: »
    Thanks for sharing, and the other contributions, I just started using a Taylor scale with body fat measures so will be monitoring. Maybe try another scale, perhaps the one you use has a problem? I am reluctant to throw out the whole idea of it. And you dont mention it, but I assume you have checked that you are not in fact losing muscle, do you exercise much, and what kind? I am mindful of this because I have no problem running but am trying to incorporate more strengthening as well.

    It's not the scale it's the the technology

    It doesn't work
  • Ian_Davies
    Ian_Davies Posts: 122 Member
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    I used to have the Tania BC-558 Ironman Segmental Body Composition Monitor. It would give me each limb, water, muscle, body fat, display the record, even metabolic age...the only problem was if i weight myself before and after my morning shower the results were totally different. The results post shower were always better but with my skin still damp I learned that the resistance was less.

    I'm hooked on monitoring progress, seeing stats, little incremental improvements but the tech just isn't there for home use so I just use a mirror.

    A friend uses a myotape and its on my christmas list. Dexa scans cost £75 in the UK but i'd prefer to buy a training session or two for that.
  • robertw486
    robertw486 Posts: 2,392 Member
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    It's simply technology that is easily influenced by too many factors. I've found things similar to what @Ian_Davies above talks about that will change the results quite a bit in minutes. Including things as simple as having a coffee or two. Unless you are extremely consistent with when you weigh, how, when and what you eat, when you exercise, how well you hydrate, how moist your skin is, and more, they will vary a lot.

    We have an older HealthOMeter type and it's easily fooled. They might serve some purpose to show an overall trend if you weigh yourself fairly frequently, but the swings are just out of control at time.
  • senecarr
    senecarr Posts: 5,377 Member
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    Bioimpedance is fairly inaccurate, the most you can rely on it is to be consistent - given the same conditions, it can produce semi repeatable result, so if you have access to one that you can use in the same hydration state, the trend might be meaningful.

    There's only one truly accurate way to know body fat percentage, and unfortunately no one can ever get their own results from it.