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3 months later. Same weight. Different BF% *pic*

bethybum31
bethybum31 Posts: 2 Member
edited August 2021 in Health and Weight Loss
Hi MFP.
I weighed myself yest, weight is the same as 3x months previous. I used the same brand/store/scales. However my BF% is significantly different. I have done zero exercise lately so no chance of 'fat has turned to muscle'. Is this just proof that these type of scales are Very inaccurate..? I think so! But I'd be interested to hear your thoughts.

20210813_224634.jpg

Replies

  • MaltedTea
    MaltedTea Posts: 6,286 Member
    edited August 2021
    Since there are kids in my home, there are several "profiles" set up. If I don't catch it sometimes, my scale assumes I'm not me due to weight and body composition changes. Mind you, it's like 12+ years old too.

    Even if you're the sole user, try a reset.

    Then be sure to use the device at the same time, under similar conditions (such as weighing yourself while fasted, evacuated and naked at the same time every day)
  • AnnPT77
    AnnPT77 Posts: 35,305 Member
    If it's just two readings, then inaccuracy is certainly the likeliest.

    If a person uses the same scale, weighs often, they may be able to get a rational trend line that gives them a rough idea which *direction* body composition is heading over a longer time period, but they may need to ignore the occasional blip or outlier where the BIA scale was fooled by unusual hydration or something.

    I wouldn't put much faith in the accuracy of absolute value of the percentages, though, even when there's a trend.

    IOW, if over a few months, at constant weight, you were to see BF% 26.4, 26.6, 26.3, 26.2, 26.0, 26.2, 28.5, 28.1, 26.0, 25.8, 26.0, 26.1 . . . . you might reasonably conclude that the 28s were random outlier mis-measurements, and that there was an overall down-trend in bodyfat (probably). It might really not be "around 26%", maybe it's higher or lower in absolute value, but the trend still can be providing information.

    If weight isn't constant, and the scale gives a percent, I think it's easier for the average person to get a better idea of what's being estimated if they calculate the implied BF pounds. If body weight drops, but BF% stays constant at (say) 30%, that's 30% of a declining number, so probable loss of body fat implied, y'know? One might not like the idea that lean & fat are being lost proportionally in that scenario, but there's still fat loss being estimated.