Body fat percentage scales: do they work?

townsend08002
townsend08002 Posts: 1 Member
edited November 13 in Fitness and Exercise
I just ordered a scale off of amazon that also displays your body fat percentage when you step on the scale. I was wondering how accurate are these scales? I know some folks here have had DEXA scans done, was wondering if any of you have compared the results from your scan to your scale's reading and seen how close they were?

Replies

  • trigden1991
    trigden1991 Posts: 4,658 Member
    There are a number of threads on here about them which I would advise you read. The simple answer is NO. They are not accurate and can be manipulated by any number of things (clothing, water,etc) but can be used as a long term tracking tool alongside weight.
  • Wheelhouse15
    Wheelhouse15 Posts: 5,575 Member
    If you take a pool of people the answer is yes, they do well statistically speaking but the variance is rather large so you could be way off depending how far you are away from the model they use for calculating the bf%. For me it's way off but for some it will be within a point or two of their actual BF%. DEXA, Bod Pod or water tank is best but scales can at least give you the relative changes over time, which can be just as important.
  • Sumiblue
    Sumiblue Posts: 1,597 Member
    I have a cheap one I bought at a discount store a couple years ago. I used it to track my progress but didn't put too much confidence in the number. I got a Bodpod last January and a hydrostatic test in Spring of last year. They were within 1-2% of what my scale gave me. Scale was lower. But, I can weigh myself several times within seconds and get different readings. So, not accurate. It was probably just coincidence that my scale and the more accurate tests were close.
  • Wheelhouse15
    Wheelhouse15 Posts: 5,575 Member
    Sumiblue wrote: »
    I have a cheap one I bought at a discount store a couple years ago. I used it to track my progress but didn't put too much confidence in the number. I got a Bodpod last January and a hydrostatic test in Spring of last year. They were within 1-2% of what my scale gave me. Scale was lower. But, I can weigh myself several times within seconds and get different readings. So, not accurate. It was probably just coincidence that my scale and the more accurate tests were close.

    It means that your confirm almost perfectly to the model and that your lower and upper body are fairly similar in fat distribution. It's certainly not bad when it works out that way.
  • sijomial
    sijomial Posts: 19,809 Member
    I had some 4 point BIA scales (hand & feet sensors) which agreed pretty closely with six monthly BodPod scans - but you had to use common sense to even out the expected fluctuations mainly caused by hydration variations.
    With some experimentation I knew the trend showed by my first thing in the morning results would be "reasonable" - most of the time.

    By the way would only regard BodPod scans as silver standard compared to gold standard DEXA or hydrostatic testing, but they are cheaper, convenient and non-invasive.
    Seeing a trend is helpful but wouldn't put much faith in the actual numbers.

    IMHO 2 point scales (or measuring devices) are virtually worthless as you are at best only putting the current through half your body. I've got some bathroom scales that will tell me I'm currently way over 30% BF even though my legs are very lean.
  • thunder1982
    thunder1982 Posts: 280 Member
    My bathroom scales were pretty close to the 4 point bia scales at the nutritionist office. Mine generally give consistent numbers with multiple weighs at the same time. I only use in the morning when hydration would likely be more consistent. But really it's for tracking a trend not pin point accuracy.
  • Wheelhouse15
    Wheelhouse15 Posts: 5,575 Member
    edited November 2016
    sijomial wrote: »
    I had some 4 point BIA scales (hand & feet sensors) which agreed pretty closely with six monthly BodPod scans - but you had to use common sense to even out the expected fluctuations mainly caused by hydration variations.
    With some experimentation I knew the trend showed by my first thing in the morning results would be "reasonable" - most of the time.

    By the way would only regard BodPod scans as silver standard compared to gold standard DEXA or hydrostatic testing, but they are cheaper, convenient and non-invasive.
    Seeing a trend is helpful but wouldn't put much faith in the actual numbers.

    IMHO 2 point scales (or measuring devices) are virtually worthless as you are at best only putting the current through half your body. I've got some bathroom scales that will tell me I'm currently way over 30% BF even though my legs are very lean.

    It's your age that's confounding your weight I would imagine. The older you are the more the models tend to jump due to the natural tendency of people to lose muscle and gain fat but people who continue to lift heavy as they age aren't going to see the decrease in muscle that the majority of the population experiences. If you dial down your age about 20 years it should be far more accurate.
  • sijomial
    sijomial Posts: 19,809 Member
    sijomial wrote: »
    I had some 4 point BIA scales (hand & feet sensors) which agreed pretty closely with six monthly BodPod scans - but you had to use common sense to even out the expected fluctuations mainly caused by hydration variations.
    With some experimentation I knew the trend showed by my first thing in the morning results would be "reasonable" - most of the time.

    By the way would only regard BodPod scans as silver standard compared to gold standard DEXA or hydrostatic testing, but they are cheaper, convenient and non-invasive.
    Seeing a trend is helpful but wouldn't put much faith in the actual numbers.

    IMHO 2 point scales (or measuring devices) are virtually worthless as you are at best only putting the current through half your body. I've got some bathroom scales that will tell me I'm currently way over 30% BF even though my legs are very lean.

    It's your age that's confounding your weight I would imagine. The older you are the more the models tend to jump due to the natural tendency of people to lose muscle and gain fat but people who continue to lift heavy as they age aren't going to see the decrease in muscle that the majority of the population experiences. If you dial down your age about 20 years it should be far more accurate.

    @Wheelhouse15
    My age is a problem in soooo many ways!! :neutral:

    I actually gave up trying to estimate BF%, partly as I had no interest in being very lean (can look scrawny on an old fart!) but really found it irrelevant for me once I got to "healthy" levels. Mirror and exercise performance tells me all I need to know.
  • Sumiblue
    Sumiblue Posts: 1,597 Member
    Sumiblue wrote: »
    I have a cheap one I bought at a discount store a couple years ago. I used it to track my progress but didn't put too much confidence in the number. I got a Bodpod last January and a hydrostatic test in Spring of last year. They were within 1-2% of what my scale gave me. Scale was lower. But, I can weigh myself several times within seconds and get different readings. So, not accurate. It was probably just coincidence that my scale and the more accurate tests were close.

    It means that your confirm almost perfectly to the model and that your lower and upper body are fairly similar in fat distribution. It's certainly not bad when it works out that way.

    I'd love to believe that is true but I've always been bottom heavy. I come from a long line of pear shaped women. I'm maintaining now because I lost too much fat in my upper body trying to chase after losing lower body fat. It is more evenly distributed now but I'm still carrying more fat on my lower body. I'd say muscle is evenly distributed, though.
  • Wheelhouse15
    Wheelhouse15 Posts: 5,575 Member
    sijomial wrote: »
    sijomial wrote: »
    I had some 4 point BIA scales (hand & feet sensors) which agreed pretty closely with six monthly BodPod scans - but you had to use common sense to even out the expected fluctuations mainly caused by hydration variations.
    With some experimentation I knew the trend showed by my first thing in the morning results would be "reasonable" - most of the time.

    By the way would only regard BodPod scans as silver standard compared to gold standard DEXA or hydrostatic testing, but they are cheaper, convenient and non-invasive.
    Seeing a trend is helpful but wouldn't put much faith in the actual numbers.

    IMHO 2 point scales (or measuring devices) are virtually worthless as you are at best only putting the current through half your body. I've got some bathroom scales that will tell me I'm currently way over 30% BF even though my legs are very lean.

    It's your age that's confounding your weight I would imagine. The older you are the more the models tend to jump due to the natural tendency of people to lose muscle and gain fat but people who continue to lift heavy as they age aren't going to see the decrease in muscle that the majority of the population experiences. If you dial down your age about 20 years it should be far more accurate.

    @Wheelhouse15
    My age is a problem in soooo many ways!! :neutral:

    I actually gave up trying to estimate BF%, partly as I had no interest in being very lean (can look scrawny on an old fart!) but really found it irrelevant for me once I got to "healthy" levels. Mirror and exercise performance tells me all I need to know.

    The mirror has the final say!
  • Wheelhouse15
    Wheelhouse15 Posts: 5,575 Member
    Sumiblue wrote: »
    Sumiblue wrote: »
    I have a cheap one I bought at a discount store a couple years ago. I used it to track my progress but didn't put too much confidence in the number. I got a Bodpod last January and a hydrostatic test in Spring of last year. They were within 1-2% of what my scale gave me. Scale was lower. But, I can weigh myself several times within seconds and get different readings. So, not accurate. It was probably just coincidence that my scale and the more accurate tests were close.

    It means that your confirm almost perfectly to the model and that your lower and upper body are fairly similar in fat distribution. It's certainly not bad when it works out that way.

    I'd love to believe that is true but I've always been bottom heavy. I come from a long line of pear shaped women. I'm maintaining now because I lost too much fat in my upper body trying to chase after losing lower body fat. It is more evenly distributed now but I'm still carrying more fat on my lower body. I'd say muscle is evenly distributed, though.

    The model probably has a pear-shaped bias as this is a fairly common distribution for women but it looks like you've reduced that pear to a minimum. :)

  • Sumiblue
    Sumiblue Posts: 1,597 Member
    ^^^ha, thanks! I'm definitely less of a pear now. Amazing what muscle can do.
  • jemhh
    jemhh Posts: 14,261 Member
    edited November 2016
    My home BIA scale says 27%. My DEXA in August said 36%. Visual estimates put me at 26%. Calculations range from 26-29%.

    ¯\_(ツ)_/¯
  • Bluepegasus
    Bluepegasus Posts: 333 Member
    I have a scale at home that shows body fat percentage, and whilst I realise it's not 100% accurate, I feel it does show it fairly close. Plus it has been helpful on my weightloss journey to see the bodyfat percentage coming steadily down.
  • sunny_d22
    sunny_d22 Posts: 316 Member
    I just ordered a scale off of amazon that also displays your body fat percentage when you step on the scale. I was wondering how accurate are these scales? I know some folks here have had DEXA scans done, was wondering if any of you have compared the results from your scan to your scale's reading and seen how close they were?

    I was very surprised that my body fat scale very closely matched my dexa scan. It was not a happy surprise because I learned the high body fat of my scale was actually correct!
This discussion has been closed.