Eating Below your BMR... Why is it bad?
Replies
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If there is a general acceptance that BMR is what it is (and I think there is enough science to back it up) then isn't it just common sense that eating less than that is a bad thing?
No, because as I've stated ad naseum -- you HAVE TO put your body into energy deficiency to lose weight. Whether that's below BMR or above it.0 -
Figure 4 shows that even on 800 calorie/day diets, the weight loss was overwhelmingly water and fat. During the low-carb phase, the loss was 61.2% water, 35% fat, and 3.8% protein. During the mixed phase, the loss was smaller, mostly because less water was lost: 37.1% water, 59.5% fat, and 3.4% protein.
The subjects all had BMRs much greater than 800 calories/day. Table 2 shows BMRs ranging from 1555 to 2380, two or three times the 800 calories they ate during the experiment.
Table 2 also show the changes in weight and changes in BMR. For half of the six subjects, the two track exactly. (In other words, the BMR reduction was simply due to weight loss.) In two subjects, the BMR reduction was about 50% higher than you'd expect just from the weight loss. And in one subject, the BMR increased even though the weight was down by 13%, the exact opposite of the so-called starvation mode!
I certainly don't see that study as supporting either of these propositions:
1. Eating less than your BMR will cause you to lose muscle instead of fat.
2. Eating less than your BMR will slow down your metabolism and put you in "starvation mode."
Perhaps the second proposition was true in 2 of the 6 subjects. Not true in the other 4.
Well, no where did I state that you would lose muscles "instead" of fat. In all posts I stated that you lose both whatever you do. But that study does indeed show the ratios of loss, that you can then compare to other studies, like the second one I linked in that post. Of course you will lose fat, and tons of it on a diet like that, but the ratio of muscles you lose is higher that it needs to be too. And as far as I know, no study has been done that directly compares such samples, you have to check body composition weight loss from different studies, and that's not ideal.
Another key part that is left out of every low cal diet study I have read so far is the part where you are supposed to go back to your normal routine. Not because you give up, but because you actually did it, you are at your goal weight, congratulations, now what? What I have read on that subject is that less than 1% of people on diets keep the weight off in the long run. Which has lead me to rather change my activity level, and eat above my BMR to sustain it.
Anyway, thanks for sharing your replies and challenging my opinion on this
There certainly is a lack of studies on the exact subject of "What happens to people when they eat X cals below their BMR for Y months", but every study I have seen so far seems to point that it would not be the ideal way to go. 0 -
Human beings are, at their core, animals. Our bodies are made for survival. The reason it will start to consume muscle before fat, when faced with a large caloric deficit, is for survival. As many posters have pointed out, muscle burns more calories than fat, and so getting rid of it is the most efficient step to take. The other reason is that fat is an insulator. In the days before modern homes and food supplies, staying warm was just as important as staying fed (maybe even more so, since you can freeze to death a lot faster than you can starve to death). Our modern way of living evolved in a very short amount of time, whereas our bodies have not.
Ok.. Then why is a calorie deficit above BMR different than one below it? Wouldn't both eat muscle first?0 -
???I like the way Vaclav Gregor (Greg) put it....All credit goes to Greg.
Metabolic slow down & “Starvation modeâ€
According to diet programs, you should experience metabolic slow down or starvation mode, when you are not eating regularly or eating below your BMR (explanations differ sometimes, which I found very entertaining btw). There is no study that would support that, quite the contrary. But instead of some research that you will not understand I’ll give you the most simple and logic explanation. Just look at the pictures of people who survived the holocaust or some tragedy and have been left for months or years without food. Did they trick the metabolism and starvation mode? I don’t think so. That means that eating less or fasting will not put you into “starvation mode†and your metabolism will not slow down.
It’s really nothing to be concerned about. These things exist only to confuse you and trick you into buying more food and supplements. It’s just business, sad but true. There are tons of researches and none of them will ever speak about things like starvation mode and metabolic slow down. In this researches when people lost a lot of weight there metabolism slowed down about 100 calories. That’s one large coffee. And I would say that it didn’t slow down, it just came to the normal level from being overweight. Why? Because BMR (Basal Metabolic Rate) is calculated by your height and your lean body mass. So when you lose weight, your lean body mass number decreases.
actually, just a quick search on ncbi returned some "non-existent" studies. for example:
http://www.ncbi.nlm.nih.gov/pubmed/18842775
pay attention to "total energy expenditure -- in particular, energy expenditure at low levels of physical activity -- is lower than predicted by actual changes in body weight and composition."
and if you go through reference list of this paper you'll find more.
I don't understand how people throw around statements like "there are no studies supporting..." without checking themselves if this was really true...0 -
It burns muscle first when in too great a defecit because muscle requires energy to sustain, whereas fat doesn't, and doesn't give two craps about how your muscles look - it's designed to keep you alive, not pretty.Sounds bogus to me, I believe its just made up and spread over and over on the MFP forums.
Why would your body attack muscle first instead of fat for energy? That would be quite stupid
I can see it using muscle for protein it needs, but not energy.
I don't believe your BMR is the magical cut off for your body to start eating your muscle tissue, if someone can prove to me otherwise I stand corrected
Eat at a deficit to your TDEE and you will lose weight. Eat at too great a deficit for your body to sustain, and you will lose the wrong kind of weight. Eating above your BMR ensures your body has enough energy and nutrition to sustain lean mass and to burn the less efficient fuel - fat.0 -
If there is a general acceptance that BMR is what it is (and I think there is enough science to back it up) then isn't it just common sense that eating less than that is a bad thing?
No, because as I've stated ad naseum -- you HAVE TO put your body into energy deficiency to lose weight. Whether that's below BMR or above it.
You're ignoring the point made earlier about people who have a lot of weigh to lose. Anyone whose BMR is where yours is and who can eat 2000+ calories per day and still be at a "Deficit" is obviously going to be able to get the nutrients they need from all the food they're allowed to eat. This is not the case for people who are much closer to their healthy goal weight and have a BMR around 1500. If they deficit the 500 that you do - they're then expected to survive (in a healthy way) off of 500 calories a day? NOT going to happen. The body will start to shut down and whenever goal weight IS reached and maintenance calories (i.e. TDEE) is resumed, all of a sudden the weight will pop right back on, because the body is singing: YAY FAT! STORE IT! KEEP IT! DON'T LOSE IT AGAIN BECAUSE WE NEED IT!0 -
I like the way Vaclav Gregor (Greg) put it....All credit goes to Greg.
Metabolic slow down & “Starvation modeâ€
According to diet programs, you should experience metabolic slow down or starvation mode, when you are not eating regularly or eating below your BMR (explanations differ sometimes, which I found very entertaining btw). There is no study that would support that, quite the contrary. But instead of some research that you will not understand I’ll give you the most simple and logic explanation. Just look at the pictures of people who survived the holocaust or some tragedy and have been left for months or years without food. Did they trick the metabolism and starvation mode? I don’t think so. That means that eating less or fasting will not put you into “starvation mode†and your metabolism will not slow down.
The one BIG point that you didn't take into account about starvation mode in the haulocoust is that those victiums never had the opportunity to eat any thing else. What happens with people that have access to food looks something like this: Jane eats 1350 calories a day(her bmr is 1650). For a bit she looses weight supper fast. She notices that she is low on energy and hungry all of the time. All of a sudden she quits loosing. James metabolism has slowed down to meet the 1350 calories a day and her body isn't a fat burning machine. Actually her body is doing it's best to bum as little energy as possible. So Jane knocks her calories down to 1200 the same cycle happens. Now Jane has the chore of eating less, but she is so flipping tired that she dosent have the energy to cook for herself. Jane throws her diet out the window. When she starts eating again her metabolism is so slow it burns as little *kitten* possible and she gains back twice as much weight! And in this whole prosscess she is screwing her hormones so out of whack that shell have to get medical help for it later.
But you guys seem to know it all so go ahead and tell people that it's all just a sham. Go ahead and encurage people to starve themselves and not to eat enuff to have the energy to build lean mucel to help their bodies stay fit long after they have reached a goal. That's way cool!!
It’s really nothing to be concerned about. These things exist only to confuse you and trick you into buying more food and supplements. It’s just business, sad but true. There are tons of researches and none of them will ever speak about things like starvation mode and metabolic slow down. In this researches when people lost a lot of weight there metabolism slowed down about 100 calories. That’s one large coffee. And I would say that it didn’t slow down, it just came to the normal level from being overweight. Why? Because BMR (Basal Metabolic Rate) is calculated by your height and your lean body mass. So when you lose weight, your lean body mass number decreases.
I'm sorry... have you seen those pictures of people from the holocaust? They sure looked starved to me. No muscle, no fat, just skin and bones. What did their internal organs look like? Is that what you would like to look like?
What everyone is saying you CAN eat below... but it is NOT recommended for Health reasons. No one wants you to look like a Holocaust Survivor or end up in the hospital because your organs have shut down since they were not needed.
But the “Starvation mode†idea here is that you can not loose weight in starvation mode. You have to increase those calories above the BMR. to loose. That is not true. It may be unhealthy but if you have a lot of weight to loose it can be done.0 -
Human beings are, at their core, animals. Our bodies are made for survival. The reason it will start to consume muscle before fat, when faced with a large caloric deficit, is for survival. As many posters have pointed out, muscle burns more calories than fat, and so getting rid of it is the most efficient step to take. The other reason is that fat is an insulator. In the days before modern homes and food supplies, staying warm was just as important as staying fed (maybe even more so, since you can freeze to death a lot faster than you can starve to death). Our modern way of living evolved in a very short amount of time, whereas our bodies have not.
Ok.. Then why is a calorie deficit above BMR different than one below it? Wouldn't both eat muscle first?
Not sure you understand the difference between BRM and TDEE?
BMR = The calories your body needs to survive (in a healthy way) just lying down doing NOTHING. Breathing and being still. Not getting up to go the the bathroom. Not chewing gum. Not lifting up the remote control and changing channels.
TDEE = BMR AND all the activity you do all day long, be it exercise, walking to your car, having sex, whatever...
If you eat below BMR, you're not giving your body the MINIMUM it needs on a day-to-day basis, just to exist. You take the deficit from the TDEE because you will still be eating more than enough to survive but less than what you expend overall doing whatever it is you do during the day.0 -
You're ignoring the point made earlier about people who have a lot of weigh to lose. Anyone whose BMR is where yours is and who can eat 2000+ calories per day and still be at a "Deficit" is obviously going to be able to get the nutrients they need from all the food they're allowed to eat. This is not the case for people who are much closer to their healthy goal weight and have a BMR around 1500. If they deficit the 500 that you do - they're then expected to survive (in a healthy way) off of 500 calories a day? NOT going to happen. The body will start to shut down and whenever goal weight IS reached and maintenance calories (i.e. TDEE) is resumed, all of a sudden the weight will pop right back on, because the body is singing: YAY FAT! STORE IT! KEEP IT! DON'T LOSE IT AGAIN BECAUSE WE NEED IT!
But you've ignored where i've said that I thing a very large caloric deficit is unhealthy. I understand that as someone who has a lot of weight to lose, I'm in a different boat than someone who has to lose 20 pounds.
The problem is, the "Do not eat below your BMR" is a general guideline that "prescribed" to everyone. That's the whole mantra of fat2fit radio, for example. They even assign your calorie consumption based on this assumption -- no matter what your size is.0 -
Another key part that is left out of every low cal diet study I have read so far is the part where you are supposed to go back to your normal routine. Not because you give up, but because you actually did it, you are at your goal weight, congratulations, now what? What I have read on that subject is that less than 1% of people on diets keep the weight off in the long run. Which has lead me to rather change my activity level, and eat above my BMR to sustain it.
I certainly can't argue with that. I'm wondering myself what I will do as I approach my goal. Certainly returning to the diet and exercise routine that caused me to gain 20 pounds in a couple of years is not the way to go.
For me this is purely scientific curiosity. I never set my weight loss goal higher than 1 lb per week, so I never had a calorie goal below my BMR. But I understand the situation of the original poster. I'd say his goal of 2 lbs per week is perfectly reasonable for someone his size. But a 1000 calorie deficit is always going to be below BMR for a sedentary person . . . unless one has a BMR higher than 4000!0 -
???
actually, just a quick search on ncbi returned some "non-existent" studies. for example:
http://www.ncbi.nlm.nih.gov/pubmed/18842775
pay attention to "total energy expenditure -- in particular, energy expenditure at low levels of physical activity -- is lower than predicted by actual changes in body weight and composition."
and if you go through reference list of this paper you'll find more.
I don't understand how people throw around statements like "there are no studies supporting..." without checking themselves if this was really true...
For some reason, I can't read the whole article, but the abstract seemed like it was more about how after weight loss, there is a slower metabolism that doesn't "bounce back" right away. I've seen other studies that do suggest that it does.
But I didn't see anything in the abstract about eating above/below your BMR.0 -
???
actually, just a quick search on ncbi returned some "non-existent" studies. for example:
http://www.ncbi.nlm.nih.gov/pubmed/18842775
pay attention to "total energy expenditure -- in particular, energy expenditure at low levels of physical activity -- is lower than predicted by actual changes in body weight and composition."
and if you go through reference list of this paper you'll find more.
I don't understand how people throw around statements like "there are no studies supporting..." without checking themselves if this was really true...
For some reason, I can't read the whole article, but the abstract seemed like it was more about how after weight loss, there is a slower metabolism that doesn't "bounce back" right away. I've seen other studies that do suggest that it does.
But I didn't see anything in the abstract about eating above/below your BMR.
Direct link : http://www.ajcn.org/content/88/4/906.long#R30
Maybe you can read it from there. It's actually very nice, I had not come across that one so far. But I don't think it links to BMR though.0 -
I will be away from the computer for awhile, so won't be checking this thread. Please don't feel ignore.
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after I read the initial post on this thread, it got me thinking about BMR & TDEE and the simplest way to understand it
found this great website that clearly says what they are and why it's important
http://www.build-muscle-and-burn-fat.com/how-many-calories-should-i-eat-tdee.html
be warned though, there are heaps of ads on that page! 0 -
You lose muscle through inactivity. Simple.
Your body won't start to canabalis(sp?) itself (lean muscle) if your using those muscles semi regularly. I believe I read somewhere once a week is the lowest you can go.
However, you won't gain muscle in this environment. Regardless of how hard you work out. This idea you lose muscle is exclusive to the sedentary, and quite frankly if you are.... then likely you don't give a **** in the first place. For those of us who work for a body, rather than exclusively diet, do!
Having said this, the only other option left, when your eating below this arbitrary BMR, is to reduce the furnace. Which lowers your metabolism. Long term, severe enough causes serious health issues.
The best way to go about it, is to eat enough to float above this number and the energy you expend during a day which is the TDEE. Then take your deficit from that, responsibly.
Hence move more, eat less. But unless your really move more, and those who do, know they do..... move more eat more applies better.0 -
bumpity bump0
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You lose muscle through inactivity. Simple.
While this is true, it's far from being that simple...
Bodybuilders, that train 6-7 days a week, you can hardly say that they don't "use" their muscles, report muscle loss overnight, in the simple 8-10 hours fast everyone does every day.
http://www.t-nation.com/free_online_article/sports_body_training_performance_nutrition/the_top_10_post_workout_nutrition_myths
Check point 3, it cites a nice study on the subject. So this "once a week" sounds quite a lot like bro-science Muscle loss is inevitable in a process of weight loss, but some ways to lose weight are just worse than others. 0 -
You lose muscle through inactivity. Simple.
While this is true, it's far from being that simple...
Bodybuilders, that train 6-7 days a week, you can hardly say that they don't "use" their muscles, report muscle loss overnight, in the simple 8-10 hours fast everyone does every day.
http://www.t-nation.com/free_online_article/sports_body_training_performance_nutrition/the_top_10_post_workout_nutrition_myths
Check point 3, it cites a nice study on the subject. So this "once a week" sounds quite a lot like bro-science Muscle loss is inevitable in a process of weight loss, but some ways to lose weight are just worse than others.
Is there a possibility that their diet was simply not enough to maintain that muscle mass? This is before we talk about 6-7 days a week!
I think you should compare an orange to an orange, as I doubt there are BB here. Just saying.0 -
Your Basal Metabolic Rate, the energy used for super basic functions of life, mainly dealing with fluid levels, is energy supplied to each and every cell.
Fat doesn't have much water in it, so not nearly as much there, but still some, muscle has much more, so most energy there.
Where the "energy" to deal with fluid levels and the few other things BMR does ultimately does come from carbs/fat at ratio of 30/70 at rest, you ultimately can't provide energy into a system that you are getting energy from totally.
We do not have little perpetual motion machines in our body, if we did, you could lose fat by just not eating for long while, and yet that is not what happens, because it's not what the body does.
The body slows down.
It is totally incorrect to say that muscle becomes some more used energy source than carbs/fat. The ratio of usage doesn't change just because the metabolism slowed down.
That is the main bad effect of eating below your BMR, your whole metabolism slows down. What could have burned 500 cals now burns only 300 cals. Your body at rest could have burned 1600 cals, now burns 1200 cals.
Is it bad that your weight loss takes longer? Your decision.
But - if you go too low, by having exercise take some of your eaten calories before the body can do BMR functions, it must slow down even more now.
You can get to the point where what you are eating is actually maintenance level. And you will have no weight loss.
The muscle breakdown problem comes into play because usually when you calorie restrict too much at very low levels (nothing to do with eating below BMR though), you don't get enough carbs to top of limited storage. When that limited storage is depleted, the only thing to convert into needed carbs is muscle.
But if your BMR is 2000, and you eat at 1500, and your BMR becomes 1500 (or below actually), you are likely eating enough carbs to prevent that from happening.
You are still slowing down your metabolism eventually though. If you exercise and burn 300 calories every day and don't eat it back, your BMR will have to lower eventually to the 1200 it is left with. How long of a lag time? 3 days to 3 weeks for diminishing weight loss?0 -
I like the way Vaclav Gregor (Greg) put it....All credit goes to Greg.
Metabolic slow down & “Starvation modeâ€
According to diet programs, you should experience metabolic slow down or starvation mode, when you are not eating regularly or eating below your BMR (explanations differ sometimes, which I found very entertaining btw). There is no study that would support that, quite the contrary. But instead of some research that you will not understand I’ll give you the most simple and logic explanation. Just look at the pictures of people who survived the holocaust or some tragedy and have been left for months or years without food. Did they trick the metabolism and starvation mode? I don’t think so. That means that eating less or fasting will not put you into “starvation mode†and your metabolism will not slow down.
It’s really nothing to be concerned about. These things exist only to confuse you and trick you into buying more food and supplements. It’s just business, sad but true. There are tons of researches and none of them will ever speak about things like starvation mode and metabolic slow down. In this researches when people lost a lot of weight there metabolism slowed down about 100 calories. That’s one large coffee. And I would say that it didn’t slow down, it just came to the normal level from being overweight. Why? Because BMR (Basal Metabolic Rate) is calculated by your height and your lean body mass. So when you lose weight, your lean body mass number decreases.
I. Love. This.
I always thought that. I mean, everyone screams about starvation mode, etc, but anorexics don't suddenly pile the weight on after eating normally.
I, however, eat above my BMR. I don't want to be hungry and feel deprived, and this is working for me so far.0 -
Another key part that is left out of every low cal diet study I have read so far is the part where you are supposed to go back to your normal routine. Not because you give up, but because you actually did it, you are at your goal weight, congratulations, now what? What I have read on that subject is that less than 1% of people on diets keep the weight off in the long run. Which has lead me to rather change my activity level, and eat above my BMR to sustain it.
I certainly can't argue with that. I'm wondering myself what I will do as I approach my goal. Certainly returning to the diet and exercise routine that caused me to gain 20 pounds in a couple of years is not the way to go.
For me this is purely scientific curiosity. I never set my weight loss goal higher than 1 lb per week, so I never had a calorie goal below my BMR. But I understand the situation of the original poster. I'd say his goal of 2 lbs per week is perfectly reasonable for someone his size. But a 1000 calorie deficit is always going to be below BMR for a sedentary person . . . unless one has a BMR higher than 4000!
So true.
The only saving grace to that is the fact the BMR at very heavy weights is almost always over-inflated. Only if someone maintained the original fat/LBM of study participants the BMR formula is based on would the current BMR calc be correct.
The Katch BMR formula though using body composition would have much less deviation from truth, actually more underestimated, because the increased fat still requires some energy.0 -
You lose muscle through inactivity. Simple.
While this is true, it's far from being that simple...
Bodybuilders, that train 6-7 days a week, you can hardly say that they don't "use" their muscles, report muscle loss overnight, in the simple 8-10 hours fast everyone does every day.
http://www.t-nation.com/free_online_article/sports_body_training_performance_nutrition/the_top_10_post_workout_nutrition_myths
Check point 3, it cites a nice study on the subject. So this "once a week" sounds quite a lot like bro-science Muscle loss is inevitable in a process of weight loss, but some ways to lose weight are just worse than others.
Is there a possibility that their diet was simply not enough to maintain that muscle mass? This is before we talk about 6-7 days a week!
I think you should compare an orange to an orange, as I doubt there are BB here. Just saying.
Nah, we are talking about people eating 5-6k calories/day here, and ungodly amount of protein. The main point was just to say that maintaining muscle is not as easy as just using them somewhat frequently 0 -
I. Love. This.
I always thought that. I mean, everyone screams about starvation mode, etc, but anorexics don't suddenly pile the weight on after eating normally.
I, however, eat above my BMR. I don't want to be hungry and feel deprived, and this is working for me so far.
Well... They do... That's partly where the problem comes from. They put on weight so fast when they eat just a little more, thus fueling their idea that what they do is ok. Like was pointed out earlier though, taking anorexics as examples for metabolic damage might be pushing it, but the damage in that case is clear and very well documented.
For the bodybuilding example, the study that they cite was actually done on regular people, it's just that it's affecting BB even more. But the Phillips study it cites was done on regular population.0 -
Not that Wiki is a medical site, or anything, but I found this interesting; http://en.wikipedia.org/wiki/Starvation_response0
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I. Love. This.
I always thought that. I mean, everyone screams about starvation mode, etc, but anorexics don't suddenly pile the weight on after eating normally.
I, however, eat above my BMR. I don't want to be hungry and feel deprived, and this is working for me so far.
Well... They do... That's partly where the problem comes from. They put on weight so fast when they eat just a little more, thus fueling their idea that what they do is ok. Like was pointed out earlier though, taking anorexics as examples for metabolic damage might be pushing it, but the damage in that case is clear and very well documented.
For the bodybuilding example, the study that they cite was actually done on regular people, it's just that it's affecting BB even more. But the Phillips study it cites was done on regular population.
But do they? I'm def not speaking from experience or knowledge here, but most recoverered/recovering anorexics I see in like .. documentaries and stuff are at normal weight or still very slim.
As an anecdote, though, I can share my own experience. When I was 14, I ran away from home for 4 months and during this time, I lost a lot of weight. I was essentially starving, and got so thin that my collerbone, hipbones and ribs jutted out. When I came back home, I ate so much to compensate that the weight piled on. I've always wondered whether it was partly due to the temporary starvation or just simply my gluttony. Perhaps a combination?
For what it's worth, I think it had more to do with my diet. But I think my gluttony was partly due to the starvation. I always felt hungry, for such a long time. Even after consuming vast quantities of food.0 -
As an anecdote, though, I can share my own experience. When I was 14, I ran away from home for 4 months and during this time, I lost a lot of weight. I was essentially starving, and got so thin that my collerbone, hipbones and ribs jutted out. When I came back home, I ate so much to compensate that the weight piled on. I've always wondered whether it was partly due to the temporary starvation or just simply my gluttony. Perhaps a combination?
For what it's worth, I think it had more to do with my diet. But I think my gluttony was partly due to the starvation. I always felt hungry, for such a long time. Even after consuming vast quantities of food.
Both diet and slowed down metabolism - but not starvation mode probably.
Your maintenance level at the time could have been 1000 or less calories, so eating even 1500 everyday for a week means 1 lb. Until the metabolism starts to go back up. And that could take awhile.
Probably first week, body stored everything extra as fat, just in case this continued.
Then it may have slowly starting raising it back up.
Several case studies I've seen took 6 weeks to get metabolism back up to expected levels. So during that time, eating above what would be expected maintenance level, would mean a diminishing surplus the whole time.0 -
As an anecdote, though, I can share my own experience. When I was 14, I ran away from home for 4 months and during this time, I lost a lot of weight. I was essentially starving, and got so thin that my collerbone, hipbones and ribs jutted out. When I came back home, I ate so much to compensate that the weight piled on. I've always wondered whether it was partly due to the temporary starvation or just simply my gluttony. Perhaps a combination?
For what it's worth, I think it had more to do with my diet. But I think my gluttony was partly due to the starvation. I always felt hungry, for such a long time. Even after consuming vast quantities of food.
Both diet and slowed down metabolism - but not starvation mode probably.
Your maintenance level at the time could have been 1000 or less calories, so eating even 1500 everyday for a week means 1 lb. Until the metabolism starts to go back up. And that could take awhile.
Probably first week, body stored everything extra as fat, just in case this continued.
Then it may have slowly starting raising it back up.
Several case studies I've seen took 6 weeks to get metabolism back up to expected levels. So during that time, eating above what would be expected maintenance level, would mean a diminishing surplus the whole time.
Very interesting, thank you!0 -
you make a lot of assertions as if they are fact (such as rates of metabolism slow down etc) but provide no sourced.Your Basal Metabolic Rate, the energy used for super basic functions of life, mainly dealing with fluid levels, is energy supplied to each and every cell.
Fat doesn't have much water in it, so not nearly as much there, but still some, muscle has much more, so most energy there.
Where the "energy" to deal with fluid levels and the few other things BMR does ultimately does come from carbs/fat at ratio of 30/70 at rest, you ultimately can't provide energy into a system that you are getting energy from totally.
We do not have little perpetual motion machines in our body, if we did, you could lose fat by just not eating for long while, and yet that is not what happens, because it's not what the body does.
The body slows down.
It is totally incorrect to say that muscle becomes some more used energy source than carbs/fat. The ratio of usage doesn't change just because the metabolism slowed down.
That is the main bad effect of eating below your BMR, your whole metabolism slows down. What could have burned 500 cals now burns only 300 cals. Your body at rest could have burned 1600 cals, now burns 1200 cals.
Is it bad that your weight loss takes longer? Your decision.
But - if you go too low, by having exercise take some of your eaten calories before the body can do BMR functions, it must slow down even more now.
You can get to the point where what you are eating is actually maintenance level. And you will have no weight loss.
The muscle breakdown problem comes into play because usually when you calorie restrict too much at very low levels (nothing to do with eating below BMR though), you don't get enough carbs to top of limited storage. When that limited storage is depleted, the only thing to convert into needed carbs is muscle.
But if your BMR is 2000, and you eat at 1500, and your BMR becomes 1500 (or below actually), you are likely eating enough carbs to prevent that from happening.
You are still slowing down your metabolism eventually though. If you exercise and burn 300 calories every day and don't eat it back, your BMR will have to lower eventually to the 1200 it is left with. How long of a lag time? 3 days to 3 weeks for diminishing weight loss?0 -
I have no scientific facts or anything, but after reading ALL these posts....
about 2 weeks ago, I decided to up my calorie intake to my BMR, and this is the number 1 reason why:
Eating at my BMR, will ultimately get me to my goal weight, and make it an easier transition to maintaining.
I am trying to change my habits into a healthy, sustainable lifestyle. To me, too far below BMR and I am tired and crabby. I eat my BMR, and I have the energy to be active.
This is just a personal choice though. I think that if you are extremely overweight, you probably could go below your BMR and feel fine. So, to sum up my two cents....LISTEN to YOUR body! We are all different, and to each their own!0 -
you make a lot of assertions as if they are fact (such as rates of metabolism slow down etc) but provide no sourced.Your Basal Metabolic Rate, the energy used for super basic functions of life, mainly dealing with fluid levels, is energy supplied to each and every cell.
Fat doesn't have much water in it, so not nearly as much there, but still some, muscle has much more, so most energy there.
Where the "energy" to deal with fluid levels and the few other things BMR does ultimately does come from carbs/fat at ratio of 30/70 at rest, you ultimately can't provide energy into a system that you are getting energy from totally.
We do not have little perpetual motion machines in our body, if we did, you could lose fat by just not eating for long while, and yet that is not what happens, because it's not what the body does.
The body slows down.
It is totally incorrect to say that muscle becomes some more used energy source than carbs/fat. The ratio of usage doesn't change just because the metabolism slowed down.
That is the main bad effect of eating below your BMR, your whole metabolism slows down. What could have burned 500 cals now burns only 300 cals. Your body at rest could have burned 1600 cals, now burns 1200 cals.
Is it bad that your weight loss takes longer? Your decision.
But - if you go too low, by having exercise take some of your eaten calories before the body can do BMR functions, it must slow down even more now.
You can get to the point where what you are eating is actually maintenance level. And you will have no weight loss.
The muscle breakdown problem comes into play because usually when you calorie restrict too much at very low levels (nothing to do with eating below BMR though), you don't get enough carbs to top of limited storage. When that limited storage is depleted, the only thing to convert into needed carbs is muscle.
But if your BMR is 2000, and you eat at 1500, and your BMR becomes 1500 (or below actually), you are likely eating enough carbs to prevent that from happening.
You are still slowing down your metabolism eventually though. If you exercise and burn 300 calories every day and don't eat it back, your BMR will have to lower eventually to the 1200 it is left with. How long of a lag time? 3 days to 3 weeks for diminishing weight loss?
Well, the muscle breakdown is just basic physiology, but that doesn't appear to be the points under your request.
Here are the studies showing just how well ones can slow down and stall weight loss, because of eating to low.
Also check out almost any site on diet and weight loss and they'll share the fact your metabolism will slow down. Usually it's stated as if it must happen. But it doesn't have to unless you think you are going to get big losses the whole time.
http://www.ncbi.nlm.nih.gov/pubmed/11430776
http://www.ncbi.nlm.nih.gov/pubmed/19660148
http://www.ncbi.nlm.nih.gov/pubmed/20054213
http://www.ncbi.nlm.nih.gov/pubmed/17260010
Oh, and 1 kilojoule is 238.8 calories as we would normally call it.0
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