why is MFP underestimating my BMR??

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BitteOrca
BitteOrca Posts: 74 Member
in Health and Weight Loss
Every online calculator I've used has told me by BMR is roughly around 1400 cals. Here's one calculator that I've recently tried:

http://www.bmi-calculator.net/bmr-calculator/

I'm 5'7 and 149 lbs, by the way.

I've estimated that my TDEE is around 2,100 (I do moderate/hard exercise 3-4 times a week). So this means I should be eating around 1,600 (2,100-500) calories a day to lose weight, right? So why does MFP have me set on 1,350?? That is BELOW my BMR!

I will qualify this by saying I HAVE been losing weight since joining MFP--and not too rapidly, either. Average about a pound a week. I'm still finding this discrepancy to be really crazy. I'm afraid following MFP's guidelines may have screwed up my metabolism.

Can anyone explain? TIA!

Replies

  • fromaquasar
    fromaquasar Posts: 811 Member
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    What have you set your loss per week at? If you are very close to your goal you should look at bumping it down to 1/2 pound per week. This will give you more cals and keep the weight loss going slowly. TBH your only 50 cals below your BMR, given that most people underestimate their calories I don't think you are at risk of messing up you metabolism. Also if you're losing a pound a week that would indicate your true deficit is about 500 cals/ day (5 x 500 = 3500 cals = 1 pound).

    If you are feeling fine and seeing results I wouldn't be too worried :)

    One and one more thing - remember MFP calculates sans exercise. So if you have a low level of activity (without counting exercise) your BMR and TDEE on here is lower than some calculators as exercise calories are added, not included :)
  • uclown2002
    uclown2002 Posts: 79 Member
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    TDEE 2100 - MFP 1350 = 750 x 7=5250 = 1.5lbs weight loss per week.

    Did you ask mfp for a 1.5lbs weekly weight loss?
  • JesterMFP
    JesterMFP Posts: 3,596 Member
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    MFP gives you a goal based on how much you say you want to lose. It just subtracts a number from your TDEE (at sedentary, if that's what you entered.) It just won't go below 1200. Remember also that other online TDEE calculators include your planned workouts in your activity level, MFP doesn't, but expects you to eat back those extra calories, which would give you a higher goal (could quite easily take you up to 1600).
  • brevislux
    brevislux Posts: 1,093 Member
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    That's interesting... On this website my BMR is 100 kcals higher than in the mfp calculator, without exercise. what. 0_0
  • wildcat808
    wildcat808 Posts: 140 Member
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    MFP did the same thing to me. I went with other online sources and reset my goals on here.
  • JesterMFP
    JesterMFP Posts: 3,596 Member
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    It's not an exact science and there are a couple of different formulae that can be used to work it out. MFP uses the Mifflin-St. Jeor formula. Other sites might use the original Harris-Benedict one, or the Katch-McArdle formula.
  • BitteOrca
    BitteOrca Posts: 74 Member
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    What have you set your loss per week at? If you are very close to your goal you should look at bumping it down to 1/2 pound per week. This will give you more cals and keep the weight loss going slowly. TBH your only 50 cals below your BMR, given that most people underestimate their calories I don't think you are at risk of messing up you metabolism. Also if you're losing a pound a week that would indicate your true deficit is about 500 cals/ day (5 x 500 = 3500 cals = 1 pound).

    If you are feeling fine and seeing results I wouldn't be too worried :)

    One and one more thing - remember MFP calculates sans exercise. So if you have a low level of activity (without counting exercise) your BMR and TDEE on here is lower than some calculators as exercise calories are added, not included :)

    thanks for this. i think the discrepancy DOES come from the fact that i checked off that i have a desk job in goals--i assume that's one of the reasons why i have a lower daily allowance.

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