Calorie deficit?

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Fitnesspal said i need to eat 1200 cal a day to lose weight and my bmr is 1560 just want to know how i lose weight eating less? Did my body eats the 360 remaining on my body?

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  • KarenJanine
    KarenJanine Posts: 3,497 Member
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    BMR is the number of calories your body uses while at total rest, i.e. to keep you alive.

    Your Total Daily Energy Expenditure (TDEE) (i.e. the total number of calories your body burns in one day) is:

    BMR + TEF + NEAT + Exercise

    where TEF = thermic effect of feeding (calories burned by digestion)
    where NEAT = non-exercise activity thermogenesis (calories burned by going about your daily business, housework, showering, cooking, etc)
    where 'Exercise' = calories burned through planned exercise.

    Calculate your TDEE using an online calculator such as: http://scoobysworkshop.com/calorie-calculator/

    Eat less than your TDEE and you will lose weight. Eat at TDEE to maintain weight. Eat above TDEE to gain weight.


    Edited to add - in answer to your question, when you eat at a deficit (i.e. less than TDEE) your body will use energy reserves in your body to make up the deficit.
  • JakeBrownVB
    JakeBrownVB Posts: 399 Member
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    you shouldnt be setting your bmr (basal metaboloric rate) as your TDEE. your TDEE is going to be well above your BMR unless you are literally bed ridden every day of your life.

    1200 calories is far too low a cut as you have made a big error in calculating your TDEE and you will lose considerable lean muscle mass following that diet for any length of time.
  • Mokey41
    Mokey41 Posts: 5,769 Member
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    Fitnesspal said i need to eat 1200 cal a day to lose weight and my bmr is 1560 just want to know how i lose weight eating less? Did my body eats the 360 remaining on my body?

    MFP did some math, it doesn't think. You've set it asking for too big of a weight loss goal and it's coming back with 1200 because that's as low as it will go. You need to eat over your BMR. Choose a less aggressive goal.
  • AgnesInWonderland
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    You can compute your TDEE using the Harris-Benedict Principle.

    Harris-Benedict Principle enables calculation of an individual's recommended daily calorie intake to MAINTAIN current weight.
    Little to no exercise = BMR x 1.2
    Light exercise (1–3 days per week) = BMR x 1.375
    Moderate exercise (3–5 days per week) = BMR x 1.55
    Heavy exercise (6–7 days per week) = BMR x 1.725
    Very heavy exercise (twice per day, extra heavy workouts) = BMR x 1.9

    [got that from wikipedia. but my professors said it too... once. i guess. haha i just don't want to open my old textbook.]


    So if you have 1560 BMR with light exercise that's: 1560 x 1.375 = 2145..

    2145 is the daily calorie intake to MAINTAIN your weight.
    If you take 1200 calories a day subtract that to 2145 = you have a 945 calorie deficit.

    This is how the calorie deficit works:

    1 pound of fat it equals to 3500 calories. So, if you have 945 calories deficit a day x 7 days a week = 6615 calorie deficit.

    since it's a calorie deficit your body will "tap" on it's reserves (fat) to keep it functioning properly. It will breakdown and 'use' your fats as energy making you lose about 2lbs (1.89 lbs to be exact if we'll use math but most of weighing scales doesn't actually reflect the '.89')

    BTW, looking at your picture makes me think that the 1560 MFP gave you is already your TDEE not your BMR.
    but if you want to compute it by yourself BMR formula for women is:
    655.095 + (9.5634 x weight in kg) + (1.8496 x height in cm) - (4.6756 x your age in years)

    [got that from wikipedia too. it's the 1919 formula, there's a 1984 revision]

    http://scoobysworkshop.com/calorie-calculator/ >> to make it easier if you don't like math. hahaha
    the site used the Harris-Benedict Principle. But I don't know how the computed the BMR. cause my BMR there was different from what I have computed.

    1200 calories is not too low depending on your height and weight (which you did not state). BUT if you're 6'2 or something that's probably low.
  • jacksonpt
    jacksonpt Posts: 10,413 Member
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    Fitnesspal said i need to eat 1200 cal a day to lose weight and my bmr is 1560 just want to know how i lose weight eating less? Did my body eats the 360 remaining on my body?

    MFP did some math, it doesn't think. You've set it asking for too big of a weight loss goal and it's coming back with 1200 because that's as low as it will go. You need to eat over your BMR. Choose a less aggressive goal.

    Yep, this.
  • Thanks alot guys it helps alot as a beginner i don't know anything now i know i need to lose 40 pounds pregnancy weight :)