Body fat %- MFP vs. Body fat scale?

lindzmt22
lindzmt22 Posts: 335
edited October 6 in Health and Weight Loss
Hey all, so I recently got a Taylor body fat scale and it is telling me that my body fat percentage is 28.9. And MFP says I am 30.9. I know it's not much of a difference, except for one is in the 'obese' category and one is in the 'overweight' category. But which do you think is more accurate?

Replies

  • StacySkinny
    StacySkinny Posts: 984 Member
    I didn't know this site has a body fat percentage calculator. Cool. Where can I find that?

    I would probably go with your scale's readings, as the site is probably doing more of a guesstimate.
  • meerkat70
    meerkat70 Posts: 4,605 Member
    I have a feeling someone will be along soon to extol the wonders of callipers....
  • Kim55555
    Kim55555 Posts: 987 Member
    it doesnt really matter anyhow. just use them your bf% scale as a guide. Measure every 3 months and note the progression. these machines are just meant as a way to track your progress. Dont worry so much about the accuracy of one compared to another. That goes for whether you decide to use skin fat calipers or the tanita scale. :)
  • billmac
    billmac Posts: 51 Member
    Hi Lind You are confusing BMI and Body Fat%. The MFP number is BMI Body Mass Index. They are two different things. My experience of scales is that they are baloney as far as body fat% goes. Maybe some have better sets than I but I've found the readings to be both way out in number and inconsistent. The best way (I think) to determine body fat, if you really want to go there, is a Dexa scan
  • spottedlee
    spottedlee Posts: 372
    My experience of scales is that they are baloney as far as body fat% goes. Maybe some have better sets than I but I've found the readings to be both way out in number and inconsistent. The best way (I think) to determine body fat, if you really want to go there, is a Dexa scan
    I don't know about Dexa scan but other than that, I have to agree. Several months ago, I decided to check my body fat % after a few months without a monthly check. I had already lost about 15 pounds -- the machine said that my body fat% went up by 5%. Since then, I don't trust any of this "miricle."
  • 46and2
    46and2 Posts: 167
    I have a feeling someone will be along soon to extol the wonders of callipers....

    Truly, this is the way to go. The scales work off of electrodes in the metal feet positioning pads. It measures the amount of electrical current that runs through your body since fat cells retain water and water is a great conductor of electricity. Problem being, if you ever have swollen feet from whatever the case may be, or retaining extra water, the scale will show you as increasing body fat percentage. The callipers, if used by someone who knows the positions and how to pinch (this really is important) can provide the most accurate representation of how much body fat one has. There is a 3-site, 5-site, and 7-site test that can be done depending on the accuracy you wish to receive. Try the scales for a while if that's what you have, but back it up every month or so by seeing a PT and getting a good test done.
  • JennLifts
    JennLifts Posts: 1,913 Member
    this site does BMI I believe. which isn't Body fat.
  • Alioth
    Alioth Posts: 571 Member
    BMI (what MFP says) is always a rough estimate because it works based on averages of height/gender/age measured against weight. The 'healthy' range correlates to longer lifespan on insurance company charts. It helpful as a guideline.

    Electrical impedance is far more accurate a number than BMI because it is an actual measurement, not an estimate. But as some of the posters have mentioned, it can be fooled day by day if there is water weight gain or constipation or dehydration from sickness. (If you check wikipedia, it'll tell you the error margin for different fat % measurement methods). If you are top heavy, impedance will also give a more favorable number because it measures body fat from the hips down. If you are pear-shaped, impedance will give a worse number.

    When I got my impedance scale, I measured myself daily for a while to get a feel for what my baseline number was. And it was higher than I had been telling myself it would be! But when I started toning and building muscle and I saw the numbers go down, it was encouraging to see. Also, the scale told me I wasn't hydrated enough and I started making an effort to drink more water.

    The important factor in calculating body fat % is to be able to chart your progress. So when the fat % number goes down, you can actually see progress. And when the muscle % goes up, that's nice to see too! The important thing is to be aware of the direction you're moving in, so don't get hung up on where you are on which chart right now. Just keep moving forward!
  • lindzmt22
    lindzmt22 Posts: 335
    I have a feeling someone will be along soon to extol the wonders of callipers....

    Lol I figured the same thing, but that's why I didn't mention them. Just trying to pick between these two options at the moment. :)
  • lindzmt22
    lindzmt22 Posts: 335
    BMI (what MFP says) is always a rough estimate because it works based on averages of height/gender/age measured against weight. The 'healthy' range correlates to longer lifespan on insurance company charts. It helpful as a guideline.

    Electrical impedance is far more accurate a number than BMI because it is an actual measurement, not an estimate. But as some of the posters have mentioned, it can be fooled day by day if there is water weight gain or constipation or dehydration from sickness. (If you check wikipedia, it'll tell you the error margin for different fat % measurement methods). If you are top heavy, impedance will also give a more favorable number because it measures body fat from the hips down. If you are pear-shaped, impedance will give a worse number.

    When I got my impedance scale, I measured myself daily for a while to get a feel for what my baseline number was. And it was higher than I had been telling myself it would be! But when I started toning and building muscle and I saw the numbers go down, it was encouraging to see. Also, the scale told me I wasn't hydrated enough and I started making an effort to drink more water.

    The important factor in calculating body fat % is to be able to chart your progress. So when the fat % number goes down, you can actually see progress. And when the muscle % goes up, that's nice to see too! The important thing is to be aware of the direction you're moving in, so don't get hung up on where you are on which chart right now. Just keep moving forward!

    Thank you for this helpful and well thought out response. Very appreciated!!
  • lindzmt22
    lindzmt22 Posts: 335
    Thanks everyone for the responses! When I get a chance I would like to do the calliper method, but for now I guess I'll just stick to the MFP BMI as that's what I started with at the beginning of my journey. Makes more sense to me. I know it isn't 100% accurate but it'll help me guide my progress.
  • LeanMeanFitnessMachine
    LeanMeanFitnessMachine Posts: 659
    In my opinion, the BF Scale is more accurate. It measures your BF by sending electrical pulses through your body - the pulses travel faster through fat and slower through fat - so the number is determined by how fast the pulses return to the scale. Where as MFP strictly goes by height and weight.

    Also, make sure you're not confusing BMI with BF %
  • KiyaK
    KiyaK Posts: 519 Member
    LMFM is correct in how the scale measures body fat. However, this is what makes the scale inherently inaccurate. It is based on the THEORY that electricity will travel faster and slower through muscle/fat. There are TONS of other things that will speed up/slow down that electric pulse. For those devices to get an accurate reading, numerous factors must be controlled. We’re talking hydration (when/how much fluid you drink, meal timing, last time you peed, caffeine, exercise, your period) as well as humidity of the room, temperature… It’s insane.

    So… good luck with that, I guess.
  • lindzmt22
    lindzmt22 Posts: 335
    LMFM is correct in how the scale measures body fat. However, this is what makes the scale inherently inaccurate. It is based on the THEORY that electricity will travel faster and slower through muscle/fat. There are TONS of other things that will speed up/slow down that electric pulse. For those devices to get an accurate reading, numerous factors must be controlled. We’re talking hydration (when/how much fluid you drink, meal timing, last time you peed, caffeine, exercise, your period) as well as humidity of the room, temperature… It’s insane.

    So… good luck with that, I guess.

    Thanks? lol. Yes I understand that it is hard to be 100% accurate with either of these methods, and that there are lots of factors involved in it. I'm okay with that. Not gonna get wrapped up into the number; just using it as a rough guide.*shrugs*
  • Acg67
    Acg67 Posts: 12,142 Member
    Electrical impedance is far more accurate a number than BMI because it is an actual measurement, not an estimate. But as some of the posters have mentioned, it can be fooled day by day if there is water weight gain or constipation or dehydration from sickness. (If you check wikipedia, it'll tell you the error margin for different fat % measurement methods). If you are top heavy, impedance will also give a more favorable number because it measures body fat from the hips down. If you are pear-shaped, impedance will give a worse number.

    If you look here at one study, BIA was actually more inaccurate then BMI

    bia-change-spread-in-bodybuilders.png
    I’ve heard people make the argument that, while BIA may not be that accurate, it should work fine when tracking change over time. The theory, they say, is that the error should be the same each time you use it.

    The problem is that this isn’t true. As I mentioned in the article on hydrostatic weighing, the density and hydration of fat-free mass can change with weight loss. If this can affect the accuracy of hydrostatic weighing for measuring change over time, then you can be sure that the effect on BIA outcomes is going to be significantly larger.

    Researchers have looked at the accuracy of BIA for tracking body fat change over time. In one study, the disagreement between BIA and the 4-compartment model ranged from -3.6% to 4.8% for measuring change. This means you could lose 3.6% body fat, but BIA would show no change. Or, BIA could tell you that you lost 8.8% body fat when you really only lost 4%. In fact, in this study, plain ol’ bod mass index (BMI) did just as well as BIA for predicting change in body fat, except for in one person.
    BIA can be problematic because it’s a prediction based off of a prediction, so the error gets compounded. When you look at group averages for BIA measurements, there tends to be bias, with BIA often underpredicting how much fat you have. As with other techniques, the individual error rates can get high, with some research showing error rates of around 8-9%. In fact, BIA doesn’t do much better than BMI at predicting body fat in some cases. When it comes to measuring change over time, BIA can often underpredict the amount of fat loss, and the estimated change can be off by up to 8%.

    http://weightology.net/weightologyweekly/?page_id=218

    amd read through this thread as well

    http://www.myfitnesspal.com/topics/show/405385-10-difference-in-bf-results
  • LaMujerMasBonitaDelMundo
    LaMujerMasBonitaDelMundo Posts: 3,634 Member
    My experience of scales is that they are baloney as far as body fat% goes. Maybe some have better sets than I but I've found the readings to be both way out in number and inconsistent. The best way (I think) to determine body fat, if you really want to go there, is a Dexa scan
    I don't know about Dexa scan but other than that, I have to agree. Several months ago, I decided to check my body fat % after a few months without a monthly check. I had already lost about 15 pounds -- the machine said that my body fat% went up by 5%. Since then, I don't trust any of this "miricle."

    What type of body fat measurement tool did you use? Anyway as inaccurate those measurements as it seems but there is a big possibility that you lose weight but gain fat% but that isn't good because it means a big portion of the 15 lb lost came from muscles. Losing weight doesn't automatically mean fat loss. This happens especially if you're not supporting your calorie deficit with resistance training & adequate protein intake that results in muscle loss.
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