If you are not supposed to eat below your BMR...

why does MFP set my calories at 1260. That is using Lightly active and 2 lbs per week weight loss. I still have 60 lbs left to lose, I'm 38 yo, 5'6" female and I was exercising an hour each day.

I have figured my BMR at 1730 and my TDEE is 2150 using an activity level calculator. If I take 20% off of 2150 and I get 1750. That is my BMR!!

I have been using TDEE-20% since the first of August. Averaging 1750 a day and not eating back exercise calories. My diary is open. I'm down 4 lbs since I started this, but I'm still not sold on it. Plus now I am injured and will be limited in my exercise for the next month or so and I was going to refigure my calories without exercise and eat them back when I do. I was thinking that I would just take 300 off my daily calories to count for lack of exercise but that would put me at 1450, way below BMR.

I'm really confused. Is eating below BMR such a no-no?

Replies

  • Mokey41
    Mokey41 Posts: 5,769 Member
    Because MFP does math, you supply the common sense.
  • likitisplit
    likitisplit Posts: 9,420 Member
    Mokey wins the internet.
  • cwolfman13
    cwolfman13 Posts: 41,865 Member
    Because MFP does math, you supply the common sense.

    yeah...MFP is just a calculator.

    Also, why are you not "sold" on the TDEE method...given that it would appear to be working and all. BTW...nothing magical about TDEE method...it's 6 of 1 to the MFP method if you do it right. TDEE - 20% is closer to a 1 Lb per weight loss goal...I bet if you set up MFP to lose 1 Lb per week instead of 2 and ate back exercise calories, they would be roughly equivalent to the gross calories you consume with TDEE - 20%. I know for me, this was most definitely the case.

    this is all pretty basic math and science...not much you really need to be "sold" on unless you don't believe in math or the laws of thermodynamics.
  • LassoOfTruth
    LassoOfTruth Posts: 735 Member
    .
  • HealthyVitamins
    HealthyVitamins Posts: 432 Member
    I did the whole 1200 calories thing, and man - I became so dizzy and lightheaded it was horrible and it was all the time, didn't go until after a couple of days of upping calories! now i'm eating 20% below my TDEE, around 1600 calories a day, my BMR is 1350.
  • scottkjar
    scottkjar Posts: 346 Member
    You set a 2 pounds per week weight loss goal. To do that, you need to have a 1000 calorie deficit each day. That's why MFP set your caloric goal where they did.

    If you want to consume more calories, you need to change your weight loss goal to 1 pound per week. You will see MFP's caloric target rise.
  • Scienceteacher42
    Scienceteacher42 Posts: 27 Member
    In order to lose 2 lbs per week the calculator is taking 7000 calories out of your diet each week, which means it is subtracting 1000 calories each day from your maintenance. If you don't want it to drop your calories by that much, change it to 1 lb per week so it is only subtracting 500 calories.
  • Funky_Mabel
    Funky_Mabel Posts: 17 Member
    My opinion your carbs are way to high, Start easing them down till your below 80 for the day and better yet below 50 if your body is cool with that. Plus you will find those 1200 calories more satisfying
  • SpecialSundae
    SpecialSundae Posts: 795 Member
    The MFP setting can be explained by your choice to set it at 2lb loss a week. Set a more modest goal of 1lb a week and see how you get on.
  • Bridget0927
    Bridget0927 Posts: 438 Member
    You wont know your true BMR from any online calculator.

    According to all calculators mine would be over 1300 cals, I had mine actually tested with the breathing machine and its 860! thats a significant difference!

    You're body will tell you if your eating to little you'll feel like poopers.
  • sdreed25
    sdreed25 Posts: 208 Member
    You wont know your true BMR from any online calculator.

    You're body will tell you if your eating to little you'll feel like poopers.

    THIS ^^^
  • happycauseIride
    happycauseIride Posts: 536 Member
    Because MFP does math, you supply the common sense.

    yeah...MFP is just a calculator.

    Also, why are you not "sold" on the TDEE method...given that it would appear to be working and all. BTW...nothing magical about TDEE method...it's 6 of 1 to the MFP method if you do it right. TDEE - 20% is closer to a 1 Lb per weight loss goal...I bet if you set up MFP to lose 1 Lb per week instead of 2 and ate back exercise calories, they would be roughly equivalent to the gross calories you consume with TDEE - 20%. I know for me, this was most definitely the case.

    this is all pretty basic math and science...not much you really need to be "sold" on unless you don't believe in math or the laws of thermodynamics.

    I just went back into MFP setting and put in 1 lbs per week and it put me at 1760 cals a day so it matches. The only reason I'm not sold on it is in my own mind it's too many calories to lose weight. But it has been working so I won't change anything for now.
  • happycauseIride
    happycauseIride Posts: 536 Member
    I did the whole 1200 calories thing, and man - I became so dizzy and lightheaded it was horrible and it was all the time, didn't go until after a couple of days of upping calories! now i'm eating 20% below my TDEE, around 1600 calories a day, my BMR is 1350.

    I did the 1200 calorie thing too and felt like crap. I will never do that again. :)
  • happycauseIride
    happycauseIride Posts: 536 Member
    My opinion your carbs are way to high, Start easing them down till your below 80 for the day and better yet below 50 if your body is cool with that. Plus you will find those 1200 calories more satisfying

    I actually set my carbs at 45%, but the figures that were in there were MFP's numbers from me messing around with the calculator. I have no plans on eating 1200 calories. I put it back at 1750 now. :)
  • maybeazure
    maybeazure Posts: 301 Member
    If you eat below your BMR then you body will make up what it needs from its energy stores (fat). Most sources suggest that women should not eat fewer than 1200 calories a day without medical supervision, but I haven't seen any real research that proves that horrible things happen if you eat less than your BMR. Also, unless you get an expensive medical test to determine your actual metabolism, the BMR calculator is just estimating your calorie needs anyway--and based on weight, not percentage of fat/muscle, etc. If you have a greater percentage of fat than the average person, the BMR number you find could be too high.

    I've been eating less than my BMR for several months now. Nothing horrible has happened. No hair loss. I have plenty of energy to exercise. I haven't had any uncontrollable binges. My weight loss hasn't stalled.

    Eating below my BMR hasn't done anything bad, but losing some of the excess weight has improved my life immensely. I can now run twice as long as I could when I started. I have been able to completely stop my high blood pressure medication (with doctor approval). I have cut my anti-depressant in half. I love exercise now.

    Bottom line...I don't think anything horrible will happen if you eat 1400 calories a day. You will probably continue to lose weight, even if you aren't able to exercise like you used to.
  • Hildy_J
    Hildy_J Posts: 1,050 Member
    Perhaps you could try setting the exercise level on your TDEE calculation to 'sedentary' - see what it gives you?

    Hope you're on the mend soon. :-)
  • likitisplit
    likitisplit Posts: 9,420 Member
    Because MFP does math, you supply the common sense.

    yeah...MFP is just a calculator.

    Also, why are you not "sold" on the TDEE method...given that it would appear to be working and all. BTW...nothing magical about TDEE method...it's 6 of 1 to the MFP method if you do it right. TDEE - 20% is closer to a 1 Lb per weight loss goal...I bet if you set up MFP to lose 1 Lb per week instead of 2 and ate back exercise calories, they would be roughly equivalent to the gross calories you consume with TDEE - 20%. I know for me, this was most definitely the case.

    this is all pretty basic math and science...not much you really need to be "sold" on unless you don't believe in math or the laws of thermodynamics.

    I just went back into MFP setting and put in 1 lbs per week and it put me at 1760 cals a day so it matches. The only reason I'm not sold on it is in my own mind it's too many calories to lose weight. But it has been working so I won't change anything for now.

    ...but you are losing at a sustainable pace...
  • Mokey41
    Mokey41 Posts: 5,769 Member
    If you eat below your BMR then you body will make up what it needs from its energy stores (fat). Most sources suggest that women should not eat fewer than 1200 calories a day without medical supervision, but I haven't seen any real research that proves that horrible things happen if you eat less than your BMR. Also, unless you get an expensive medical test to determine your actual metabolism, the BMR calculator is just estimating your calorie needs anyway--and based on weight, not percentage of fat/muscle, etc. If you have a greater percentage of fat than the average person, the BMR number you find could be too high.

    I've been eating less than my BMR for several months now. Nothing horrible has happened. No hair loss. I have plenty of energy to exercise. I haven't had any uncontrollable binges. My weight loss hasn't stalled.

    Eating below my BMR hasn't done anything bad, but losing some of the excess weight has improved my life immensely. I can now run twice as long as I could when I started. I have been able to completely stop my high blood pressure medication (with doctor approval). I have cut my anti-depressant in half. I love exercise now.

    Bottom line...I don't think anything horrible will happen if you eat 1400 calories a day. You will probably continue to lose weight, even if you aren't able to exercise like you used to.

    If you have a considerable amount to lose you can get away with not eating your BMR because it's based on a certain percentage of lean body mass. When you are obese it messes up the numbers because it's assuming a percentage of lean body mass that isn't there and you don't need the extra calories to feed the fat.

    BMR becomes far more important the closer you get to being a normal weight. 1200 calories is a low end for a woman of normal weight to maintain body functions.
  • ZombieSlayer
    ZombieSlayer Posts: 369 Member
    Because MFP does math, you supply the common sense.

    :drinker: :drinker: :drinker: Win!
  • ladynocturne
    ladynocturne Posts: 865 Member
    If you eat below your BMR then you body will make up what it needs from its energy stores (fat). Most sources suggest that women should not eat fewer than 1200 calories a day without medical supervision, but I haven't seen any real research that proves that horrible things happen if you eat less than your BMR. Also, unless you get an expensive medical test to determine your actual metabolism, the BMR calculator is just estimating your calorie needs anyway--and based on weight, not percentage of fat/muscle, etc. If you have a greater percentage of fat than the average person, the BMR number you find could be too high.

    I've been eating less than my BMR for several months now. Nothing horrible has happened. No hair loss. I have plenty of energy to exercise. I haven't had any uncontrollable binges. My weight loss hasn't stalled.

    Eating below my BMR hasn't done anything bad, but losing some of the excess weight has improved my life immensely. I can now run twice as long as I could when I started. I have been able to completely stop my high blood pressure medication (with doctor approval). I have cut my anti-depressant in half. I love exercise now.

    Bottom line...I don't think anything horrible will happen if you eat 1400 calories a day. You will probably continue to lose weight, even if you aren't able to exercise like you used to.

    The main problem with eating below ones BMR is that our brain cannot use fat stores and convert it to energy to run, it will use lean muscle mass. The brain uses more calories than one would think. If you continue to under feed long enough, you can lose significant amounts of lean muscle mass, lowering your metabolism and ending up looking flabby at one's goal weight.
  • sweebum
    sweebum Posts: 1,060 Member
    If you have a considerable amount to lose you can get away with not eating your BMR because it's based on a certain percentage of lean body mass. When you are obese it messes up the numbers because it's assuming a percentage of lean body mass that isn't there and you don't need the extra calories to feed the fat.

    BMR becomes far more important the closer you get to being a normal weight. 1200 calories is a low end for a woman of normal weight to maintain body functions.

    This. Numbers are just *estimates*. Why not try a cut of 25% for a few weeks and then judge your progress.
  • pavrg
    pavrg Posts: 277 Member
    why does MFP set my calories at 1260. That is using Lightly active and 2 lbs per week weight loss. I still have 60 lbs left to lose, I'm 38 yo, 5'6" female and I was exercising an hour each day.

    I have figured my BMR at 1730 and my TDEE is 2150 using an activity level calculator. If I take 20% off of 2150 and I get 1750. That is my BMR!!

    I have been using TDEE-20% since the first of August. Averaging 1750 a day and not eating back exercise calories. My diary is open. I'm down 4 lbs since I started this, but I'm still not sold on it. Plus now I am injured and will be limited in my exercise for the next month or so and I was going to refigure my calories without exercise and eat them back when I do. I was thinking that I would just take 300 off my daily calories to count for lack of exercise but that would put me at 1450, way below BMR.

    I'm really confused. Is eating below BMR such a no-no?
    Your body doesn't have a calorie counter. It only has negative feedback mechanisms to tell it if it needs more or less of a substance. If it needs more and you don't eat it, it pulls from storage.

    If you are using the TDEE method, BMR is nothing more than a "that's cool" measurement. BMR is the same thing as TDEE if you stayed in bed all day. TDEE is the energy you need to sustain your metabolism at your current weight and activity level, not BMR. Eating under TDEE stimulates the body to make up energy loss, mostly from stored fat. Your body doesn't know its BMR and won't shut down if you go under it provided you are staying moderately below tdee. And most Americans living a sedentary lifestyle working a desk job will have a tdee-500 under bmr. If you were more active than that you probably wouldn't be here.

    So bottom line: your tdee is your daily energy needs. BMR is useless and it's not a magic omg starvation mode number.
  • likitisplit
    likitisplit Posts: 9,420 Member
    http://ajcn.nutrition.org/content/4/6/625.full.pdf

    "The basic minimum daily requirement of the average adult at bed rest consists of a diet containing approximately 70 g
    protein and 2400 calories, 30 per cent as fat, in addition to vitamins and minerals."

    You see, hospitals use these guidelines.
  • pavrg
    pavrg Posts: 277 Member
    What's your point? Hospitals are trying to make people retain and sometimes gain weight after being ill.
  • likitisplit
    likitisplit Posts: 9,420 Member
    "basic minimum daily requirement" does not equal "gaining weight after illness."

    and the title of the paper is "The Care and Nutrition of a Patient in Prolonged Coma"
  • pavrg
    pavrg Posts: 277 Member
    Their minimum of 2400 cal is way off -- I do a lot more activity than a coma patient with significantly less intake, and my net intake is routinely below bmr. If that really were a min, I'd be dead. The paper is written with the goal of sustaining a patient's weight.

    BMR only applies to bed ridden people. If you move around use tdee because that's what applies to you.
  • jimshine
    jimshine Posts: 199 Member
    "What's your point? Hospitals are trying to make people retain and sometimes gain weight after being ill. "

    Sometimes hospitals just give you enough to survive. I was on life support for a month..they gave me 1200 calories a day via feeding tube. When I finally woke up, I was all fat, no muscle. I could barely hold a cup.
  • trogalicious
    trogalicious Posts: 4,584 Member
    because the initial setup process for MFP is effectively broken. While it's a calculator, as many other websites are, it allows you to put in information that may not be accurate.

    Anyone can just show up and go "Oh hey, I wanna lose 2lbs per week even though I only have about 10 to really lose"... so they set up the account, set that goal, get 1200 calories as their goal for daily calories, and then don't even eat that much.

    The tool is great if used correctly, but most folks don't.
  • pavrg
    pavrg Posts: 277 Member
    Medical practices can vary widely based on a whole slew of factors. My wife had babies in two different states and they did more different than the same.

    Still has nothing to do with the topic at hand, which is the misconception op has that going below bmr will flip a switch in his body to go into starving.
  • deksgrl
    deksgrl Posts: 7,237 Member
    why does MFP set my calories at 1260. That is using Lightly active and 2 lbs per week weight loss. I still have 60 lbs left to lose, I'm 38 yo, 5'6" female and I was exercising an hour each day.

    I have figured my BMR at 1730 and my TDEE is 2150 using an activity level calculator. If I take 20% off of 2150 and I get 1750. That is my BMR!!

    I have been using TDEE-20% since the first of August. Averaging 1750 a day and not eating back exercise calories. My diary is open. I'm down 4 lbs since I started this, but I'm still not sold on it. Plus now I am injured and will be limited in my exercise for the next month or so and I was going to refigure my calories without exercise and eat them back when I do. I was thinking that I would just take 300 off my daily calories to count for lack of exercise but that would put me at 1450, way below BMR.

    I'm really confused. Is eating below BMR such a no-no?

    You are set at 2 pounds per week, which is a bit too aggressive for your amount left to lose. Set it to 1 pound per week.

    A properly set MFP goal PLUS exercise calories should be somewhere around the same ballpark as a TDEE -20% calorie goal, and if you set it to 1 pound per week I think this will give you a much closer number.