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Advice: gain 2lb but lost 2% body fat

bembo1980
bembo1980 Posts: 28 Member
edited November 2024 in Health and Weight Loss
Ok so my stats: starting weight 180lb, ultimate goal 140lb, current weight 172lb.

I've seen a steady loss in lbs over the past 3 weeks. I have stuck to my 1200 calories rigidly (except for when I run and I eat 50% back).

I weighed on Tuesday and was 3.5 lb down since the previous Tuesday. However I weighed today and have put 2lb back on !!! I am weighing everything and tracking as I eat.

But, I have gone from 42% body fat three weeks ago to 40% on Tuesday. Today I am 38%.

How can I have gained back 2lb but lost 2% fat?!?!?

Replies

  • dahhhhhling
    dahhhhhling Posts: 66 Member
    Water weight? 2 lbs is nothing, I can put on 5 lbs of water weight depending on how much sodium I have or how hard I exercise that day and then it's gone the next morning.
  • ShammersPink
    ShammersPink Posts: 215 Member
    edited February 2017
    How did you measure the BF%?

    If it is with bodyfat scales (BIA), that is a normal effect of differences in hydration levels. They are highly inaccurate, and water retention has a strong effect on them.

    The more water you are retaining, the higher your weight, and the lower your BF% reading. Therefore I typically find that if I have an apparent weight gain, the BF% goes down, and vice versa.

    Over a longer period, they do show the underlying trend.
  • AnvilHead
    AnvilHead Posts: 18,343 Member
    edited February 2017
    The most likely issue is that you're using a scale with BIA to determine your bodyfat percentage. BIA (bioelectric impedance analysis) is highly inaccurate and can fluctuate wildly even from day to day. Basically, you may as well throw a dart at a dartboard and use that number as your BF%.

    Here's a detailed research review which discusses the reliability and errors of BIA "measurements":
    The Pitfalls of Bodyfat "Measurement", Part 4: Bioelectrical Impedance (BIA)
  • ShammersPink
    ShammersPink Posts: 215 Member
    It can almost be a relief - I look at the scales, and my weight has increased - oh noes! But the BF% reading has decreased - ah, that's ok, that means it's probably just water.
  • TimothyFish
    TimothyFish Posts: 4,925 Member
    The body fat reading is probably wrong, but for what it is worth when you gain water weight your body fat percentage goes down.
  • auranya
    auranya Posts: 56 Member
    Time of the month?
  • rybo
    rybo Posts: 5,424 Member
    Weight loss isn't always linear, there are lots of fluctuations.
    And the way you are measuring your BF% is likely highly inaccurate, so probably best to not really worry about it that much. At best look for trends over a much longer time period, (months)
  • VintageFeline
    VintageFeline Posts: 6,771 Member
    You're not gaining muscle running and eating in a deficit. It's just water and unreliable methods of measuring BF%.
  • trigden1991
    trigden1991 Posts: 4,658 Member
    Water
This discussion has been closed.

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