What happens if you don't eat your BMR?

What happens if you don't eat at least your BMR amount of calories each day?

MFP says to lose 1lb a week I need to eat like 2000 calories. That seems a bit high, doesn't it?

My BMR though is like 1877.

Replies

  • ladyraven68
    ladyraven68 Posts: 2,003 Member
    What happens if you don't eat at least your BMR amount of calories each day?

    MFP says to lose 1lb a week I need to eat like 2000 calories. That seems a bit high, doesn't it?

    My BMR though is like 1877.

    What does MFP say is your daily calorie burn? ( In Goals Tab - top right hand side)

    Even if you were totally sedentary your BMR of 1877 would give you a TDEE of 2250, so 2000 doesn't seem that high.
  • Alexstrasza
    Alexstrasza Posts: 619 Member
    What happens if you don't eat at least your BMR amount of calories each day?

    MFP says to lose 1lb a week I need to eat like 2000 calories. That seems a bit high, doesn't it?

    My BMR though is like 1877.

    What does MFP say is your daily calorie burn? ( In Goals Tab - top right hand side)

    Even if you were totally sedentary your BMR of 1877 would give you a TDEE of 2250, so 2000 doesn't seem that high.

    With the calculators I've used it's said my TDEE is like 2550. So if I eat around 2000 calories I should lose weight, correct?
  • StrongGwen
    StrongGwen Posts: 378 Member
    What happens if you don't eat at least your BMR amount of calories each day?

    Here's what happens (been there done that)
    1. you feed off stored fat for a few days and get real happy about it, feeling virtuous and thinking, Oh this is easy!
    2. you start feeling tired, cranky, unwell and HUNGRY! You do not have energy to work out any more so you quit.
    3. your body begins to cannabalize the muscle tissue you do have, which lowers your overall BMR. Muscle tissue burns more calories than fat does so you just made losing weight harder for yourself.
    4. you can't battle the cravings to eat, eat, eat any more. You figure it's not worth it, I'll never lose this stupid weight and start eating everything you can reach, especially high-calorie foods.
    5. you step on the scale and say OH NO! I've got to do something about this fat!
    Repeat cycle.

    great quote "IF YOU'RE TIRED OF STARTING OVER, STOP GIVING UP."
  • ladyraven68
    ladyraven68 Posts: 2,003 Member
    What happens if you don't eat at least your BMR amount of calories each day?

    MFP says to lose 1lb a week I need to eat like 2000 calories. That seems a bit high, doesn't it?

    My BMR though is like 1877.

    What does MFP say is your daily calorie burn? ( In Goals Tab - top right hand side)

    Even if you were totally sedentary your BMR of 1877 would give you a TDEE of 2250, so 2000 doesn't seem that high.

    With the calculators I've used it's said my TDEE is like 2550. So if I eat around 2000 calories I should lose weight, correct?

    Correct. :)
  • I'm confused, because I have my acct set to the recommended setting on 1 lb per week, but it has my calorie intake at 1370 calories. My bmr (which I had to use another diet app to calculate) is 1492 and my TDEE is 2063. I'm concerned that this app "recommends" me eating less than my BMR. I do like it better for inputting calorie info though. Are my settings wrong or something? Can't seem to find a way to fix this...
  • WalkingAlong
    WalkingAlong Posts: 4,926 Member
    The app doesn't use your BMR as a floor because there is nothing wrong with eating below your BMR. Though you could always use the 'custom' goals settings instead of the 'guided' one, if you prefer a higher goal.
  • gotolam
    gotolam Posts: 262 Member
    What happens if you don't eat at least your BMR amount of calories each day?

    You lose weight.
  • omma_to_3
    omma_to_3 Posts: 3,265 Member
    What happens if you don't eat at least your BMR amount of calories each day?

    Here's what happens (been there done that)
    1. you feed off stored fat for a few days and get real happy about it, feeling virtuous and thinking, Oh this is easy!
    2. you start feeling tired, cranky, unwell and HUNGRY! You do not have energy to work out any more so you quit.
    3. your body begins to cannabalize the muscle tissue you do have, which lowers your overall BMR. Muscle tissue burns more calories than fat does so you just made losing weight harder for yourself.
    4. you can't battle the cravings to eat, eat, eat any more. You figure it's not worth it, I'll never lose this stupid weight and start eating everything you can reach, especially high-calorie foods.
    5. you step on the scale and say OH NO! I've got to do something about this fat!
    Repeat cycle.

    great quote "IF YOU'RE TIRED OF STARTING OVER, STOP GIVING UP."

    Disagree with pretty much all of this. I have seen zero scientific evidence of ANY issue eating below your BMR, but still eating an adequate amount. My BMR, as tested in a hospital is 1521. I eat below it most days though do eat back my exercise calories (my net target is 1230). I'm not hungry (most days). I don't starve myself (I eat lots of food, especially on work out days). I did lose huge amounts of weight that way. I did not cannibalize my muscle (I've done body comp tests year over year and maintained my muscle mass while dropping fat). I did not have uncontrollable cravings.

    I would welcome reading any scientific studies on this topic, so if you have some that show eating below your BMR is bad, please share.
  • Ready2Rock206
    Ready2Rock206 Posts: 9,487 Member
    I'm confused, because I have my acct set to the recommended setting on 1 lb per week, but it has my calorie intake at 1370 calories. My bmr (which I had to use another diet app to calculate) is 1492 and my TDEE is 2063. I'm concerned that this app "recommends" me eating less than my BMR. I do like it better for inputting calorie info though. Are my settings wrong or something? Can't seem to find a way to fix this...

    You can change it under settings to be a more appropriate calorie goal. If you do change it just remember that you won't be eating back exercise calories using the TDEE method. MFP assumes you will be eating them back which is why it gives a lower amount.
  • nicsflyingcircus
    nicsflyingcircus Posts: 2,861 Member
    The app doesn't use your BMR as a floor because there is nothing wrong with eating below your BMR. Though you could always use the 'custom' goals settings instead of the 'guided' one, if you prefer a higher goal.

    ^^This.

    I eat below my BMR and have for over four months. I am neither starving, withering away, nor dying to go on massive binges. I am not "hangry". I am however, still losing weight at a good clip, without exercise (which I do plan to add soon). I balance my diet and make sure I am getting plenty of protein and good fats and fiber, and I am doing fine.
  • SezxyStef
    SezxyStef Posts: 15,267 Member
    What happens if you don't eat at least your BMR amount of calories each day?

    Here's what happens (been there done that)
    1. you feed off stored fat for a few days and get real happy about it, feeling virtuous and thinking, Oh this is easy!
    2. you start feeling tired, cranky, unwell and HUNGRY! You do not have energy to work out any more so you quit.
    3. your body begins to cannabalize the muscle tissue you do have, which lowers your overall BMR. Muscle tissue burns more calories than fat does so you just made losing weight harder for yourself.
    4. you can't battle the cravings to eat, eat, eat any more. You figure it's not worth it, I'll never lose this stupid weight and start eating everything you can reach, especially high-calorie foods.
    5. you step on the scale and say OH NO! I've got to do something about this fat!
    Repeat cycle.

    great quote "IF YOU'RE TIRED OF STARTING OVER, STOP GIVING UP."

    Disagree with pretty much all of this. I have seen zero scientific evidence of ANY issue eating below your BMR, but still eating an adequate amount. My BMR, as tested in a hospital is 1521. I eat below it most days though do eat back my exercise calories (my net target is 1230). I'm not hungry (most days). I don't starve myself (I eat lots of food, especially on work out days). I did lose huge amounts of weight that way. I did not cannibalize my muscle (I've done body comp tests year over year and maintained my muscle mass while dropping fat). I did not have uncontrollable cravings.

    I would welcome reading any scientific studies on this topic, so if you have some that show eating below your BMR is bad, please share.

    x2.

    I ate below my BMR when I first came here...none of the above happened.

    2k isn't a lot of calories...I lose on that too...not fast but I still lose.

    MFP if you enter your data for reasonable weight loss will give you good numbers to follow but it does expect you to eat back some of your exercise calories....
  • michikade
    michikade Posts: 313 Member
    Eating below BMR can cause issues more for people who have less body fat - it's hard enough to maintain muscle mass on a deficit anyway but if you have a lower BF% your body won't have much choice but to take from the muscles. Your body cares a whole lot less about your guns than it does about keeping your heart and brain functioning.

    Also, eating below BMR CAN mean that you aren't getting enough nutrients (but this is not a guarantee - some people have a fairly high BMR and can get adequate nutrition under that, while others have a very low BMR).
  • dbmata
    dbmata Posts: 12,950 Member
    What happens if you don't eat at least your BMR amount of calories each day?

    MFP says to lose 1lb a week I need to eat like 2000 calories. That seems a bit high, doesn't it?

    My BMR though is like 1877.

    You turn into a lizard person.
  • ninerbuff
    ninerbuff Posts: 48,992 Member
    If someone has like 5lb-10lbs to lose and has a BMR of say 1200, eating -500 calories a day may be disastrous. Of course their actual TDEE has to be taken into account too.
    But for someone who very overweight (say a BMR of 2000 and is 80lbs-100lbs overweight) eating under BMR shouldn't be a big issue.

    A.C.E. Certified Personal and Group Fitness Trainer
    IDEA Fitness member
    Kickboxing Certified Instructor
    Been in fitness industry for 30 years and have studied kinesiology and nutrition
  • ChrisM8971
    ChrisM8971 Posts: 1,067 Member
    What happens if you don't eat at least your BMR amount of calories each day?

    MFP says to lose 1lb a week I need to eat like 2000 calories. That seems a bit high, doesn't it?

    My BMR though is like 1877.

    You turn into a lizard person.

    I thought it was a pumpkin!

    Seriously though, there is no issue with eating below your BMR particularly if you have a reasonable amount of weight to lose. When I started I was obese and sedentary and the only way to get a sufficient deficit to lose 1.5 lb per week was to eat below my BMR

    Now that I am more active and have slowed my weight loss as I approach my goal I eat above my BMR
  • DeguelloTex
    DeguelloTex Posts: 6,652 Member
    So far, I've lost 58 pounds in 4 months.
  • Jetta_C
    Jetta_C Posts: 58
    Keep in mind the algorithms behind BMR on any website are going to be pretty simplistic. I pretty much ignore what they recommend for me and instead eat until I feel satisfied. Through experimentation I've found that a lower carb diet, especially in the last half of the day, is more satisfying and allows me to eat less, but that is just me. You'll have to find what combo works best for you.

    In sum, always think of any generically calculated number to be a rough estimate and no more. No one knows your body and metabolism as well as you.
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    What happens if you don't eat at least your BMR amount of calories each day?

    I did it for a while and lost weight and felt fine. I'm currently eating more than my BMR, however (at least what I think my BMR is, none of us really know for sure), because I'm pretty active. What matters is how aggressive your overall deficit is (you don't want it too high), not how it happens to compare with BMR.
    MFP says to lose 1lb a week I need to eat like 2000 calories. That seems a bit high, doesn't it?

    Depends on your stats, but not necessarily. It's based on your height, weight, age, and activity level. MFP figures your NEAT (burn from everything BUT exercise) and subtracts 500 from that for a 1 lb loss. Based on your BMR the number makes sense, especially if you are at least lightly active.
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    I'm confused, because I have my acct set to the recommended setting on 1 lb per week, but it has my calorie intake at 1370 calories. My bmr (which I had to use another diet app to calculate) is 1492 and my TDEE is 2063. I'm concerned that this app "recommends" me eating less than my BMR. I do like it better for inputting calorie info though. Are my settings wrong or something? Can't seem to find a way to fix this...

    MFP's number is before exercise, and the TDEE number includes exercise. That's why there's a difference. (Although it isn't related to eating below BMR or not.) In theory, if you ate about 1563/day or if you ate 1370 plus a reasonable estimate of exercise (which seems to be 200/day or 1400/week based on the TDEE calculator results) you'd be in the same place.