Mythical BMR

douglasmobbs
douglasmobbs Posts: 563 Member
in Health and Weight Loss
Why do so many people say you should not eat under your BMR? Some even try and get slightly scientific saying that the BMR shows how many calories your body needs to survive if in a coma.

1. People who log on here are not in a coma, we are moving about so burning more calories.
2. BMR is an estimate. Just look at the different values you get from the different equations.

http://www.journals.elsevierhealth.com/periodicals/yjada/article/S0002-8223(95)00366-5/abstract

3. What is a lot more important is the nutritional quality of what you eat rather than the calorie value. Who has a healthier diet, both have a calculated BMR of 1,500. One eats 1,600 calories of lard each day the other eats 1,300 calories in a mix of lean meats, vegetables, fruit and grain.

4. When overweight your body has an adequate source of energy in the fat that makes you overweight.
«1

Replies

  • mcarter99
    mcarter99 Posts: 1,666 Member
    I think people believe it because it kind of sounds right. (It's not.) Like this:

    If you have two items that add up to $1.10 and one costs $1 more than the other, how much do they cost? Most people will say one item costs $1 and the other costs ten cents. (It's not right.)
  • BaconMD
    BaconMD Posts: 1,165 Member
    Everything is an estimate, not just BMR / RMR formula results. Packaging labels, database entries, HRM readouts. Everything. Just because a value is an estimate doesn't mean there is no value to it whatsoever. For example, when I get an estimate from my mechanic to fix my car, it may be a little more or a little less, but the estimate serves the purpose to tell me the ballpark I'm looking at.

    If your body has an adequate source of energy in your fat, why even bother to eat anything at all? Why not just use up all of your fat and start eating once you've lost a bunch of weight?
  • douglasmobbs
    douglasmobbs Posts: 563 Member
    If your body has an adequate source of energy in your fat, why even bother to eat anything at all? Why not just use up all of your fat and start eating once you've lost a bunch of weight?

    3. What is a lot more important is the nutritional quality of what you eat rather than the calorie value.
  • sigma54
    sigma54 Posts: 28 Member
    You do need to eat something... you need at least some carbohydrates/sugar since this is the only fuel your brain can use. You do have some carbohydrate storage but not enough to last very long.
  • rainbowbow
    rainbowbow Posts: 7,490 Member
    You do need to eat something... you need at least some carbohydrates/sugar since this is the only fuel your brain can use. You do have some carbohydrate storage but not enough to last very long.

    Yes, pretty much this.
  • lizziebeth1028
    lizziebeth1028 Posts: 3,602 Member
    People can really obsess about the numbers on here!! I sometimes get like that too. It will make you crazy!!!

    If you have a lot to lose and your normal calorie intake 'pre-diet' was say 2400......then just eat less!!!! Pick a number less than 2400 and more than 1200 and go with it for awhile. See if it works!! It's not rocket science. It does get trickier as you get closer to goal and those dreaded plateaus happen. That I will admit. Or if you are hard core, body builder or runner...I can see the 'science' coming into play then. But for someone just starting out - eat less, move more!
  • mcarter99
    mcarter99 Posts: 1,666 Member
    What you need to eat is usually recommended to be 1200 for women. For many of us, our BMR is higher. When MFP tells people to eat at 1200 to meet their goals and they come in the forums and hear that's dangerous, it just muddies the waters. 1200 is not dangerous.
  • lporter229
    lporter229 Posts: 4,907 Member
    People can really obsess about the numbers on here!! I sometimes get like that too. It will make you crazy!!!

    If you have a lot to lose and your normal calorie intake 'pre-diet' was say 2400......then just eat less!!!! Pick a number less than 2400 and more than 1200 and go with it for awhile. See if it works!! It's not rocket science. It does get trickier as you get closer to goal and those dreaded plateaus happen. That I will admit. Or if you are hard core, body builder or runner...I can see the 'science' coming into play then. But for someone just starting out - eat less, move more!

    EXACTLY!
  • emnk5308
    emnk5308 Posts: 736
    All I can say about this entire BMR, eat more thing.. is I've been eating 1100 every day..sometimes eating back exercise cal's sometimes not. I'm not dead yet, I've got TONS O.O of energy.. and I'm losing weight. I eat very good and take vitamins.

    I'm fine. IF I stall out and stop losing weight.. I'll consider it as an option.. I'll give it a try and see what happens.
  • chrisb75
    chrisb75 Posts: 395 Member
    So if BMR is a myth, you are saying that there isn't some number of calories that your body burns at rest? What is your source that it is a myth?
  • BaconMD
    BaconMD Posts: 1,165 Member
    You do need to eat something... you need at least some carbohydrates/sugar since this is the only fuel your brain can use. You do have some carbohydrate storage but not enough to last very long.

    Yes, pretty much this.
    So how many grams of healthy carbs must I consume in a day in order to live off of my body fat? I think the paleo diet says 50 grams for accelerated fat loss, so that's about 200 calories.
  • carld256
    carld256 Posts: 855 Member
    I think the record for fasting is 14 months. You can definitely live on your reserves of fat for a while, and doctors routinely put morbidly obese patients on very low calorie supervised diets with good results. BMR is a good rule of thumb, but it's not magic, and the way many people here use "starvation mode" doesn't seem to be backed by any real science.
  • chrisb75
    chrisb75 Posts: 395 Member
    All I can say about this entire BMR, eat more thing.. is I've been eating 1100 every day..sometimes eating back exercise cal's sometimes not. I'm not dead yet, I've got TONS O.O of energy.. and I'm losing weight. I eat very good and take vitamins.

    I'm fine. IF I stall out and stop losing weight.. I'll consider it as an option.. I'll give it a try and see what happens.

    All I will say about the low calorie thing is that when I was eating low calories, I was dizzy, zero energy, couldn't compete a workout. Since I bumped my calories to 2500 a day, I am still losing weight, I have added 100lbs to my squat, 110 to my dead lift, etc. I have tons of energy, my concentration has improved, and I look great.
  • carld256
    carld256 Posts: 855 Member
    So if BMR is a myth, you are saying that there isn't some number of calories that your body burns at rest? What is your source that it is a myth?

    Well, of course the body burns a certain number of calories at rest, and BMR is real, I just don't think it's as important as many people believe. There is eventually a metabolic slow down if you don't eat enough, but from what I remember reading it only kicks in at a low body fat percentage.
  • chrisb75
    chrisb75 Posts: 395 Member
    So if BMR is a myth, you are saying that there isn't some number of calories that your body burns at rest? What is your source that it is a myth?

    Well, of course the body burns a certain number of calories at rest, and BMR is real, I just don't think it's as important as many people believe. There is eventually a metabolic slow down if you don't eat enough, but from what I remember reading it only kicks in at a low body fat percentage.

    Not true at all:
    http://www.bodybuilding.com/fun/core_march_8.htm
  • carld256
    carld256 Posts: 855 Member
    If you're going to link to something as proof you're going to have to do better than a bodybuilding blog.
  • vade43113
    vade43113 Posts: 836 Member
    bump for future reading
  • LittleButMightyOne
    LittleButMightyOne Posts: 117
    BMR is not a myth. The online calculators are just pretty worthless. There are actual ways to calculate it. I have been going to my gym to use their InBody 230 machine every couple months or so to measure my progress. It calculates my weight, BMI, % body water, % and pounds of body fat, pounds of muscle, and my BMR.

    I took it in April and my goal then was to lose fat, increase muscle, and thereby raise my BMR. Between then and 2 days ago, my fat had decreased 3.8 pounds, my muscle had increased 1.5 pounds, and my BMR had increased from 1341 to 1368. That's an actual number, not an online estimation.

    And "starvation mode" is also not a joke. I just read a paper that said healthy patients were put on a 3 day fast; their BMR decreased 8% in that time, a significant reduction!
  • chrisb75
    chrisb75 Posts: 395 Member
    If you're going to link to something as proof you're going to have to do better than a bodybuilding blog.

    Did you read the article or just dismiss it. Where are your sources for all the crap you have claimed.
  • IronPlayground
    IronPlayground Posts: 1,594 Member
    There are a lot of people that just want to lose weight. Period! They really don't care how they get there. The problem with that thinking is they really don't know what they are going to look like at their predetermined "goal" weight. Some like what they see when they achieve their goal and some are disappointed.

    Others, have a different goal in mind. That would be to preserve a set amount of lean mass and burn fat. This requires a different type of food intake. It is more strict with regards to macros and calories.

    Eating under BMR or at a 20% cut from TDEE is really dependent on your goals.
  • UpsideMeagan
    UpsideMeagan Posts: 67 Member
    If you're going to link to something as proof you're going to have to do better than a bodybuilding blog.

    But people are supposed to take what random posters take as gospel? Please.
  • Trechechus
    Trechechus Posts: 2,819 Member
    1) BMR is not a myth. It is an estimate.
    2) Everything is an estimate. Calories are not actual things, it is an arbitrary number assigned to energy to make it more understandable and workable. This has been helpful to me, particularly in chem labs
    3) If you do not feed your body the number of calories it needs, it is going to start leaching from the already existing stores in your body.

    Keep in mind that you are a rather large organism (I mean in the grand scheme of organisms. You are, for instance, unmistakably larger than, say, a paramecium.) You need to maintain your large body and all it's functions with a given amount of energy in the form of ATP. Without going into a huge explanation of cellular respiration and the citric acid cycle, I'm just going to state that your body is going to make sure if gets adequate material to feed into the citric acid cycle to make ATP. If you don't eat it, it's going to start getting it from your muscles, from your bones and not just from your fat reserves.

    Long story short. EAT YOUR CALORIES AND DON'T EAT BELOW BMR

    Reference: My biology degree
  • Articeluvsmemphis
    Articeluvsmemphis Posts: 1,987 Member
    I basically use the calorie estimate as a guide, sort of. i don't eat more if I'm not hungry, but will eat over my allotted calories if I need to. i just tell people to feel it out, and see where they function the best.
  • carld256
    carld256 Posts: 855 Member
    If you're going to link to something as proof you're going to have to do better than a bodybuilding blog.

    Did you read the article or just dismiss it. Where are your sources for all the crap you have claimed.

    All what "crap" exactly? The only factual, not opinion, thing that I claimed was that starvation mode doesn't kick in until you hit about 5% body fat. That was the conclusion of the Minnesota starvation studies. The site you linked to is completely anecdotal and describes one person. Show me a controlled study, where food is actually monitored, that shows me starvation mode is real and results from eating below your BMR (not actually starving) and I'll believe you.
  • mcarter99
    mcarter99 Posts: 1,666 Member
    If you're going to link to something as proof you're going to have to do better than a bodybuilding blog.

    Did you read the article or just dismiss it. Where are your sources for all the crap you have claimed.

    "An initial review of this woman's calories indicates she is just above starvation level in the 400-700 per day range."

    How is this relevant?
  • carld256
    carld256 Posts: 855 Member
    If you're going to link to something as proof you're going to have to do better than a bodybuilding blog.

    But people are supposed to take what random posters take as gospel? Please.

    Did I ask you to take what I said as gospel? I reported something I thought I remembered reading. If you want to twist that around to me claiming that I'm right no ifs and or otherwises, that's your fault.
  • mcarter99
    mcarter99 Posts: 1,666 Member
    http://www.youtube.com/watch?v=bpAvFsIUxvY

    He's basically just a trainer/blogger but he's got a lot of education:

    My formal education background is a degree in human biology and nutrition from the University of Guelph (Ontario Canada), and a Masters In Human Biology and nutrition also from U of Guelph.

    I did further graduate research and taught exercise physiology at the University of Florida (Go Gators!)

    I’ve taken a bunch of personal training certifications, all the usual ones such as the NSCA CSCS, ACE PT, CSEP etc. I was also a certified kinesiologist blah blah, if you’ve taken any of these certifications you know how BS they are…I personally don’t put any value in these certificates because they’re not hands on and just require a simple written test…so yeah I have em’ but I don’t think they mean anything.
  • RayRay1500
    RayRay1500 Posts: 158 Member
    If you're going to link to something as proof you're going to have to do better than a bodybuilding blog.


    :laugh: :laugh: :laugh: :laugh: :laugh:
  • traderjodie
    traderjodie Posts: 2
    I think a few concepts are being confused in this discussion. There is clearly some number of calories that your body burns every day just to run its autonomic systems. What we don't know (and scientists don't know it yet either) is what percentage of that number can you supply from your own fat stores before doing temporary or permanent damage. I can not say this emphatically enough. The answer to this question is not yet settled regardless of what dieting websites and books try to tell you.

    But don't forget that while you are trying to lose weight, you also have to go on with your daily life. You have to go to work, take care of family, walk the dog, etc. And you probably need to be mentally and physically able to do that. There is a point at which you simply don't function well, physically or mentally. Whether your weight loss actually slows down is probably also an unsettled scientific question but your quality of life certainly can slow down.

    For a fascinating study of how our functioning breaks down without calories, I recommend the book, "The great starvation experiment" by Todd Tucker. This study followed a group of conscientious objector volunteers during WWII to study the effects of starvation in order to find the best way to "refeed" a starved continent once the war ended. It is truly eye opening.

    There is probably a sweet spot, where you are eating a nutritionally balanced diet of sufficient calories to let you function as a decent human being and still lose weight at an acceptable rate. My guess is that everyone will have to find that spot on for him or herself. The sad part is that it probably will change as you lose weight and age but thats life! 1200 is probably a decent place to start but there is nothing magic about that number.
  • douglasmobbs
    douglasmobbs Posts: 563 Member
    What is a myth is the importance of the number with reference to weight loss.

    If anybody can show me true accurate scientific research that identifies why you should not eat below your BMR I will be amazed.

    This is not an argument about the health problems associated with under eating it is linking what you need, when overweight hence wanting to lose weight, to a calorific value particularly BMR.

Categories