Body fat calculator on scales

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Can some one please let me know how to get body fat percent values. I had an old scale which calculates body fat percent. It shows a value of 33% based on my height, weight, gender and age. I just bought a new one and it shows a value of 38.7%. Not sure which one to trust. Below are the scales I have.

http://www.amazon.com/Tanita-UM-028-Body-Fat-Monitor/dp/B002KYPKVS (shows 33%)
http://www.amazon.co.uk/gp/product/B003X3A3EY/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1 (shows 38.7%)

Just to add a bit more information. My old scale has 4 contacts for body fat measurement and the new one has 2.

Replies

  • Cherimoose
    Cherimoose Posts: 5,209 Member
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    The second one has much better reviews, so it's probably more accurate. Keep in mind that all bodyfat scales are rarely 100% accurate, and changes in your hydration can affect the results. You might try comparing results to skinfold calipers (below). They are fairly accurate if used correctly (hard to self-test though):

    http://www.amazon.com/AccuFitness-Accu-Measure-Body-Fat-Caliper/dp/B000QURRUK
  • michikade
    michikade Posts: 313 Member
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    I don't think that a scale will provide complete accuracy, but you could check with another method and see which one gave you the most similar result.

    I found this site with a few different ways to test body fat percentage:

    http://www.builtlean.com/2010/07/13/5-ways-to-measure-body-fat-percentage/

    Some of them are pricy but the first couple options can be done at home assuming you measure in the same place each time.
  • disasterman
    disasterman Posts: 746 Member
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    I agree that these are not the most accurate way to check but they still have some value if it's important to you to measure your progress. If you use the scale at the same time of the day -I'd recommend first thing in the morning - you'll probably find it to be very consistent over time. Keep a spreadsheet or a log of your readings over time and you should be able to determine if your bodyfat percentage is steadily increasing, decreasing, or remaining the same.
  • AvonBell
    AvonBell Posts: 107 Member
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    There's really no accurate way to figure out body fat. If you're using bioelectrical impedance it's important to understand that the error of margin can be up to 10%. Of the other methods (i.e. DXA scans, callipers, or hydrostatic weighing) hydrostatic weighing will probably get you closest to the real number. There's still an error of margin.

    Whatever you do, take them under similar conditions (first thing in the morning is your best bet) and don't put too much stock in the trend unless the results are 3 to 6 months apart.

    IMO, the best way to go is to snap a photo and compare it to bodies online.
  • djinkx
    djinkx Posts: 3 Member
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    i've had two body fat scales - not the spency $2000+ ones, but the kind you can get at target or bed bath & beyond - and my body fat % measurement fluctuated between 32 and 37% on both. the very same morning the current scale gave me a 34% reading a bod pod test measured me at 18%. i know there's a margin of error in bod pod testing as well, but my massage guy (who's a body builder and a personal trainer) said he thought 18% was about right.

    the scale also tells me i have about 3.6% bone mass - which should be 12%-ish. so i call BS on these scales in general and don't even stay on long enough to get the reading any more - but YMMV.
  • vbvamsi
    vbvamsi Posts: 13 Member
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    Thanks very much for all the responses. I will try another method and use pictures as suggested.
  • Cortelli
    Cortelli Posts: 1,369 Member
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    i've had two body fat scales - not the spency $2000+ ones, but the kind you can get at target or bed bath & beyond - and my body fat % measurement fluctuated between 32 and 37% on both. the very same morning the current scale gave me a 34% reading a bod pod test measured me at 18%. i know there's a margin of error in bod pod testing as well, but my massage guy (who's a body builder and a personal trainer) said he thought 18% was about right.

    the scale also tells me i have about 3.6% bone mass - which should be 12%-ish. so i call BS on these scales in general and don't even stay on long enough to get the reading any more - but YMMV.

    My experience is similar (an older scale). On a morning I had both a DXA and hydro, the scale was off by 10+%. Mine may be particularly sucky, because it doesn't even really show trends very well.