Why shouldn't you eat under your BMR?

YesIAm17

I'll avoid the infinite back and forth because it never goes anywhere.

My closing statements shall be as follows...
- "Below BMR" does not equal VLCD
- Sources warning against VLCD are generally not relevant when discussing eating below BMR (because 800 calories isn't the same as say 1600 calories)
- Yes it is absolutely possible to eat at a reasonable deficit of BMR, get all of your required macros and micros, and minimize LBM loss
- For me personally, eating at what I consider a reasonable deficit of TDEE (calculated using HB or KM) puts me below BMR and I have not the slightest concern about this. I have not consulted a doctor, but I seriously doubt any but a few random quacks would suggest my strategy was at all unhealthy.
...but I'm still learning.

:flowerforyou:

Mcgrawhaha

i lost all my weight in 11 months on 1200 cals net per day. far below my bmr. i am just under 5 foot 10, 33 years old... i didnt lose hair, its still thicker than ever... nails look great, not weak, have good muscle tone... and... im not in "starvation mode" maintenance being held hostage at 1200, im maintaining at 2000 cals average a day... i lived to tell about it!

just recently droppped back down to 1200 cals to take of my final 5 pounds... feeling awesome, feeling energized, and my body is functioning...

your blanket statements of the dangers of 1200 cals a day, or other low numbers are incorrect, because i have been very successfull with it, shocking my md with the results of my most recent blood work, and i also know many other women who have succeeded on low cals... its all about food choices and lifestyle... one can make low cals work, and remain healthy!

marleniap

you have to eat below your bmr in order to lose weight...you doing the right thing by eatig 1200 the only reason why your not seeing any results yet is because ur deficit of calories is so small... it takes 3,500 calories to make a pound so it is just taking longer for u to see results cuz its taking alot time for ur deficit to equal 3,500 calories. normally you eat 500-1,000 calories less a day to lose 1-2 lbs a week but you cant eat less then 1200 calories a day other wise your body goes into starvation mode.

NOPE.

OP, please ignore this "advice", it is horribly, outrageously wrong. Your BMR is the amount of calories your body needs at rest. As in, if you were comatose you would need to be taking in that amount to keep your body functioning. Eating below it, especially for long periods of time, is not intelligent.

Our bodies are wired for feast vs. famine. If we are not taking in adequate calories our body will assume it's a time of famine and hold on to as much as it can. It will eat muscle first and then fat stores, which means all these people who are eating 500+ below their BMR are not losing fat, they are losing muscle. And generally when you start eating normally again your body will cling to those extra calories because it still thinks it's in a time of famine, which is why so many people gain everything back plus some following a low-cal diet.

When a person wants to lose weight they do need a deficit, that is true. But not from your BMR. If should be taken from your total daily energy expenditure (TDEE), which is the amount of calories your body needs to have daily for all your activities; like walking, cleaning, working out, etc. If you were to take 500 calories a day from your TDEE that would create a deficit of 3,500 calories a week, equivalent to about a pound. The more you move/workout the more your body generally needs. That is why we have members here eating 2,000+ calories daily and still actively losing.

Please do your research. There are some amazing links here on MFP that are stickied to the top of the Getting Started board. Read them and learn how to stay healthy while actively losing.

Bump this

marleniap

There is no logic or science behind the "don't go below BMR ever" idea. A deficit is a deficit and will cause your body to tap into fat stores for the energy it needs. In any deficit you may also lose some muslce but getting your macros right and strength training will help minimize this.

As long as you get your required macros and micros there is no scientific evidence, anywhere, as far as I am aware, that something bad will automatically and always happen if you go below BMR.

I recommend using the calculators on iifym.com to determine your Sedentary TDEE (and eat at a 10% to 30% deficit of that depending how much and how fast you want to lose, and eat back your exercise calories) and use their calculator to determine what your macros need to be.

For those who insist that something bad will happen if you go below BMR please provide a credible source as if such exists I really would like to know. So far I've yet to see a source produced when this topic comes up on the forums.

Credible sources like my kidneys shutting down when I tried VLCD to lose weight? Or how my hair fell out? Or how my immune system took a nose dive and I struggled with fatigue? Or how when I stopped starving myself - surprise of surprises - the weight came back and brought friends?

But since you asked!

Biology’s Response to Dieting: http://ajpregu.physiology.org/content/301/3/R581.full.pdf+html

Metabolic Responses to Prolonged Weight Reduction: http://ajpregu.physiology.org/content/290/6/R1577.full.pdf+html

Three Weeks of Caloric Restriction Alters Protein Metabolism in Normal-Weight, Young Men: http://ajpendo.physiology.org/content/289/3/E446

Adipose Gene Expression in Response to Caloric Restriction and Weight Regain: http://ajcn.nutrition.org/content/94/6/1399.full.pdf+html

Calorie Restruction Increases Mitochondrial Efficiency: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1413655/pdf/pnas-0510452103.pdf

The Defense of Body Weight: http://www.ncbi.nlm.nih.gov/pubmed/23126426

I also have several book references which focus on the adaptations of the endocrine system, if you are interested.

Would you kindly share your accredited studies stating that eating under BMR/at high deficit calories is considered applicable to the general public safe for a person to pursue long them? I would really like to see them, I'm not stating this as an insult. I have a genuine curiosity about studies in favor of VLCD for the average person.

Whoa

Take a bow. That's fantastic.

I agree :P wow, thank you for so much information

This is what I was waiting for, too! Thank you! And I'm sorry you had so many health problems after eating VLCD. :-(

I'm glad I could be helpful. There is a LOT of information out there about BMR, TDEE, the dangers of VLCD, etc. This is just a handful of articles that I was able to find that gave easy to understand hypotheses. There have been further studies on specific endocrine reactions and further study on the affects of caloric deficits long term in animals.

And while yes, for some, and for a short period of time, a low calorie high deficit diet can help it is not for everyone. You have to pay close attention to what you eat to ensure you meet adequate nutrition levels. For the morbidly obese and those who have severe medical problems it can be a temporary solution, but the way that it is touted about as something "anyone" can do irks me to no end. You need to know -- truly know -- what you are doing or you risk harming yourself.

I only read your first link but it doesn't seem to say what you think it does. It references 'basal metabolic rate' only in saying that one's BMR is reduced due to the reduction of body mass. We all know that occurs. Larger people burn more. Everyone loses some lean mass when they lose weight, also.

I imagine the other articles are also not about 'eating below your BMR' but about VLCD, which you seem to use interchangeably. I think VLCD is more commonly believed to be like 800 calories and below. Many of us are well below our BMR when we eat at 1200 calories, which is universally considered a safe number for women.

Bump

chatogal

I cant get the vision out if my head of everyone dropping dead the MINUTE they go below their BMR...because THEIR BODIES WILL STOP FUNCTIONING!!!!

Chevy_Quest

@Chatogal - I call it the MFP Rapture :drinker:

I cant get the vision out if my head of everyone dropping dead the MINUTE they go below their BMR...because THEIR BODIES WILL STOP FUNCTIONING!!!!

brower47

i lost all my weight in 11 months on 1200 cals net per day. far below my bmr. i am just under 5 foot 10, 33 years old... i didnt lose hair, its still thicker than ever... nails look great, not weak, have good muscle tone... and... im not in "starvation mode" maintenance being held hostage at 1200, im maintaining at 2000 cals average a day... i lived to tell about it!

just recently droppped back down to 1200 cals to take of my final 5 pounds... feeling awesome, feeling energized, and my body is functioning...

your blanket statements of the dangers of 1200 cals a day, or other low numbers are incorrect, because i have been very successfull with it, shocking my md with the results of my most recent blood work, and i also know many other women who have succeeded on low cals... its all about food choices and lifestyle... one can make low cals work, and remain healthy!

My grandmother smoked cigarettes for 50 years before she quit. She's now 93 and amazingly healthy for her age.

Those blanket statements about the dangers of cigarettes, or other tobacco products are incorrect, because she has been very successful at living without any negative effects. Her MD is amazed at her level of health and I know many other tobacco users who haven't had any issues... it's all about choices and lifestyle... once can use tobacco, and remain healthy!

Anecdotal statements are anecdotal.

I don't think anyone is going to die eating below BMR (relatively) or even suffer massive negative health effects. I won't do it because I want to maintain as much LBM as possible. So I eat a modest deficit, eat a lot of protein and routinely engage in weight bearing exercises. I don't want to lose all the weight as fast as I can and then spend years putting back on the muscle that I lost over a few months in the race to be thin. I want my metabolism to always be at its highest possible rate so that when I move into maintenance calorie intakes, I get to eat the highest number possible thus helping me to stick with my goal weight and not yo yoing from high to low. I want it permanent. I don't want a quick fix. I don't want to come back to MFP every year and say "this time it's for real" or "I'm back again and this time it's staying off" I want to do it once and never again. It's taken me four years to take off 40 lbs. I don't' care if it takes another four to take off the final 20.

Eat less than your BMR if you want, it won't kill you. Just be sure than you know all of the reasons why other people don't and ask yourself if getting there quicker outweighs any possible cons to taking it off more slowly.

WalkingAlong

I think it's a terrific choice to lose at a slow pace. But I think that for people who want to lose 1-2 lbs/week, that's also a good choice. Many, many people get impatient and quit dieting and remain overweight. I think the very common rec to shoot for 1-2 lbs/week is because it's a good balance of 'fast enough for continued motivation' vs. 'slow enough for good health and for new habits to take root.'

TigerBite

Bump...because I'd like some real answers.

I was once told (can't remember the person's name on here, unfortunately), that eating under your BMR for weight loss is not unhealthy if it's temporary. I believe the reason he said it was because your BMR is the calories it takes for your body to function, but for weight loss, if you eat less than BMR, your body can use fat reserves for fuel. If you are at your goal weight, however, it makes sense that you would not want to eat below BMR because your body would be using your muscles or other source to fuel itself, hence losing weight when you don't want to.

I'd like somebody to confirm or dispute this because I'm not sure if it's right, either.

Dispute:

Your body burns both fat and muscle while in a deficit ... The less aggressive the deficit, the more muscle is spared ... Since eating below your BMR would put you in a pretty aggressive deficit, you would be losing more muscle, thus lowering your overall metabolic rate (because of a decrease in LBM) by the time you reach your goal weight, making your goal weight harder to maintain ...

Edited because of autocorrect ...

brower47

I think it's a terrific choice to lose at a slow pace. But I think that for people who want to lose 1-2 lbs/week, that's also a good choice. Many, many people get impatient and quit dieting and remain overweight. I think the very common rec to shoot for 1-2 lbs/week is because it's a good balance of 'fast enough for continued motivation' vs. 'slow enough for good health and for new habits to take root.'

Warning: Anecdotal evidence follows

That's an interesting way to look at it, that need to keep motivation. It is definitely motivating to see the scale numbers drop. I've seen lots of people keep that motivation when they lost their weight. Then I saw them motivated when they lost that same amount of weight, plus a few extra pounds a year later and then I saw their motivation a third time when they lost that initial weight again, plus even more weight.
/end anecdotal evidence

I don't know what the fix is honestly. If they can't motivate themselves to lose it slowly enough to firmly develop new eating habits and a better relationship with food so that they never get started on the right path to begin with, what do you do? I hate seeing the returnees though too. I hate that I know each time they lose that weight (and haven't spent the interim gaining back the muscle they lost) their metabolism is just a tiny bit smaller. It's sad when they've done it so many times that they finally just give up and say "I just wasn't meant to be thin, or an average weight for my height and weight." Or when they start to think like this woman:

http://www.youtube.com/watch?v=WGLwzbvx4S4&list=HL1384306838

I guess I don't have a solution. And since I don't have one, I'll just keep truckin the way I am.

Good luck to everyone, may you find the approach that gets the weight off and keep it off for the long term.

Edit: darn typos

AlongCame_Molly

you have to eat below your bmr in order to lose weight...you doing the right thing by eatig 1200 the only reason why your not seeing any results yet is because ur deficit of calories is so small... it takes 3,500 calories to make a pound so it is just taking longer for u to see results cuz its taking alot time for ur deficit to equal 3,500 calories. normally you eat 500-1,000 calories less a day to lose 1-2 lbs a week but you cant eat less then 1200 calories a day other wise your body goes into starvation mode.

No.

No.

No.

No.

No.

All of it.

Just.....no.

ninerbuff

Your BMR is what your body requires to function

Don't eat less than what your body requires to function

This is incorrect. One's BMR is that calories needed to to keep one's weight the same. If someone is 400lbs, they can definitely eat below their BMR to lose weight even if active.
If someone is at a "normal" weight, then eating at their BMR or slightly above (depending on activity) will keep their weight the same.

A.C.E. Certified Personal/Group FitnessTrainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 30 years and have studied kinesiology and nutrition

One's BMR are the calories needed to keep one's weight the same when the body remains completely at rest.

TDEE are the calories needed to keep one's weight the same when taking into account specific activity levels.

Someone with less than 50 lbs to lose should avoid eating below BMR.

Someone with a lot to lose can eat below BMR but should only do so under the supervision of a qualified specialist in order to make sure that individual is eating a nutritionally balanced diet which can be hard to do when limited to very low calories.

I disagree here. Say you have a female 20 years old, a weight of 170lbs (say 120 is her goal) and she's quite sedentary. Her BMR would be approximately 1592. Add on say 400 calories for being sedentary for a TDEE of 1992. If she at at 500 calorie deficit, she'd be under her BMR.

A.C.E. Certified Personal/Group FitnessTrainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 30 years and have studied kinesiology and nutrition

Iwishyouwell

I don't think anyone is going to die eating below BMR (relatively) or even suffer massive negative health effects. I won't do it because I want to maintain as much LBM as possible. So I eat a modest deficit, eat a lot of protein and routinely engage in weight bearing exercises. I don't want to lose all the weight as fast as I can and then spend years putting back on the muscle that I lost over a few months in the race to be thin. I want my metabolism to always be at its highest possible rate so that when I move into maintenance calorie intakes, I get to eat the highest number possible thus helping me to stick with my goal weight and not yo yoing from high to low. I want it permanent. I don't want a quick fix. I don't want to come back to MFP every year and say "this time it's for real" or "I'm back again and this time it's staying off" I want to do it once and never again. It's taken me four years to take off 40 lbs. I don't' care if it takes another four to take off the final 20. Eat less than your BMR if you want, it won't kill you. Just be sure than you know all of the reasons why other people don't and ask yourself if getting there quicker outweighs any possible cons to taking it off more slowly.

And yet every single statistic notes that the percentage of people who rebound after weight loss is miserably high.

Regardless of the method, and pace, of weight loss.

There is literally no evidence that the "right" approach produces a significant advantage in the long term maintenance of weight loss. Lose it fast, the statistics look bleak. Lose it slow, they look almost equally as bleak. All of us are fighting against the odds, not with just weight loss, but more so with real, long term weight loss maintenance.

This idea that slow and steady wins the race, that if you do it all right it'll significantly increase your chances of keeping it off is a lovely fairy tale that dieters and "lifestyle changers" wrap themselves up in to feel better about some rather tough and unfortunate post-weight loss odds.

So Mcgrawhaha, or anyone like her, who's able to make a low-calorie program work for weight loss is no more of a special snowflake or unique anecdote than the millions of snails pacers who lost slow, did it the "right" way, and still regained it back. The only difference is, when moving like molasses, it makes it all that much more detrimental if you slip off too long and pile it on far faster than it took you to shed it off.

Mr_Knight

There is literally no evidence that the "right" approach produces a significant advantage in the long term maintenance of weight loss. Lose it fast, the statistics look bleak. Lose it slow, they look almost equally as bleak. All of us are fighting against the odds, not with just weight loss, but more so with real, long term weight loss maintenance.

You just shot the Easter Bunny.

MichMunchkin

you have to eat below your bmr in order to lose weight...

I....no. No. That's....no.

Siansonea

There is literally no evidence that the "right" approach produces a significant advantage in the long term maintenance of weight loss. Lose it fast, the statistics look bleak. Lose it slow, they look almost equally as bleak. All of us are fighting against the odds, not with just weight loss, but more so with real, long term weight loss maintenance.

You just shot the Easter Bunny.

Well, since he's already dead, who wants stew? :bigsmile:

Iwishyouwell

I love wabbitt. Pass me a bowl!

cwolfman13

you have to eat below your bmr in order to lose weight...you doing the right thing by eatig 1200 the only reason why your not seeing any results yet is because ur deficit of calories is so small... it takes 3,500 calories to make a pound so it is just taking longer for u to see results cuz its taking alot time for ur deficit to equal 3,500 calories. normally you eat 500-1,000 calories less a day to lose 1-2 lbs a week but you cant eat less then 1200 calories a day other wise your body goes into starvation mode.

You don't have to eat below your BMR to lose weight...you eat below your TDEE to lose weight. My BMR is 1780ish calories per these calculators...I easily lose about 1 Lb per week eating 2100 - 2200 calories because my TDEE is 2700ish.

You don't really want to eat below your BMR because you destroy more muscle mass doing that than you otherwise would eating at a sensible deficit of your TDEE.