What's the big deal about 1,200?

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  • SusanMFindlay
    SusanMFindlay Posts: 1,804 Member
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    GauchoMark wrote: »
    lemurcat12 wrote: »
    SCoil123 wrote: »
    Why are you so dead set on proving that eating below BMR long term is healthy? Since my sole point originally was the health risk and you continue to argue it I have to assume that you believe there isn't a health risk there. It's concerning.

    There's a health risk from undereating, but it isn't about BMR as people often claim (that's a myth--your body can't tell if you are under or over BMR unless you are actually immobile) or eating 1200 for a period of time. I think that's all GauchoMark is pointing out.

    Thanks, that is more or less the point. The 1200 calories has little to do with BMR and more to do with nutritional needs.

    Yes, but I'll suggest that BMR is a better proxy for nutritional needs than a blanket number (of 1200 or whatever other number you want to pick) because it factors in that taller/more muscular people need more nutrients than smaller people. If somebody did a study and showed that the best number was actually 80-90% of BMR or something like that, I'd find that credible - but I don't think such a study exists. Based on the currently available information, most people will be better off using BMR as their "calorie floor" than 1200 (or 1500 if male) just because it actually factors in their size/age/gender. (And it's worth noting that that measure allows some women a *lower* calorie floor than 1200.)
  • AnnPT77
    AnnPT77 Posts: 32,838 Member
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    GauchoMark wrote: »
    SCoil123 wrote: »
    GauchoMark wrote: »
    SCoil123 wrote: »
    GauchoMark wrote: »
    SCoil123 wrote: »
    GauchoMark wrote: »
    It must also be noted that intake isn't just about nutrients. Sure they should be the primary concern but calories purely from an energy standpoint are hella important too. Your body needs those to fuel basic bodily functions, it can't get all it needs from stored fat every day. Eating too little fat will impact hormone function and ability to absorb those precious tricky to hit on a low intake nutrients.

    Reducing body weight is important, retaining health and lean body mass is more important.

    SCoil123 wrote: »
    For me I'm 5'7" and work out daily which includes a few sessions of Insanity and weight lifting. 1200 cals would not be healthy for me. I personally don't like the idea of eating below BMR and believe long term this can be dangerous for anyone though, since that is the number your body requires for basic functions.

    While I don't recommend anyone to go sub 1200 for very long if they can lose weight other ways, I don't think these statements are correct. If you are truly getting sufficient essential nutrients and micro nutrients, the entire purpose of fat deposits are to supply energy. These statements are implying that for some reason, when we eat less than we burn, that our bodies lose the ability to oxidize fat to make up the energy deficit.

    Do either of you have anything besides opinion to back this up? I'd like to see the mechanism that would lead us to the inability to convert fat deposits to energy in times of vlc intake.

    Your BMR (Basal Metabolic Rate) is an estimate of how many calories you'd burn if you were to do nothing but rest for 24 hours. It represents the minimum amount of energy needed to keep your body functioning, including breathing and keeping your heart beating.

    I never implied that when you eat less than you burn you lose the ability to lose fat. What I said was that I do not believe it is healthy long term to eat below BMR because that is what your body needs to maintain basic function. I'm honestly not sure how you made the leap to preventing fat burn from that. I never even mentioned weight loss or fat in my reasoning as it was purely a health concern I was noting.

    The result of not eating enough to fuel basic functions like breathing and your heart beat would actually be death - not the inability to burn fat

    I understand BMR. However, energy is energy whether you get it from food or fat stores. You said that you think that if you don't EAT enough energy, that you would drop below the BMR energy requirement and that is unhealthy/dangerous. That implies that the energy from fat stores would not be used to make up the difference. Maybe that is not what you meant, but that is what I read.
    AnnPT77 wrote: »
    GauchoMark wrote: »
    It must also be noted that intake isn't just about nutrients. Sure they should be the primary concern but calories purely from an energy standpoint are hella important too. Your body needs those to fuel basic bodily functions, it can't get all it needs from stored fat every day. Eating too little fat will impact hormone function and ability to absorb those precious tricky to hit on a low intake nutrients.

    Reducing body weight is important, retaining health and lean body mass is more important.

    SCoil123 wrote: »
    For me I'm 5'7" and work out daily which includes a few sessions of Insanity and weight lifting. 1200 cals would not be healthy for me. I personally don't like the idea of eating below BMR and believe long term this can be dangerous for anyone though, since that is the number your body requires for basic functions.

    While I don't recommend anyone to go sub 1200 for very long if they can lose weight other ways, I don't think these statements are correct. If you are truly getting sufficient essential nutrients and micro nutrients, the entire purpose of fat deposits are to supply energy. These statements are implying that for some reason, when we eat less than we burn, that our bodies lose the ability to oxidize fat to make up the energy deficit.

    Do either of you have anything besides opinion to back this up? I'd like to see the mechanism that would lead us to the inability to convert fat deposits to energy in times of vlc intake.

    While I know of no mechanism for the inability to convert fat to energy while in calorie deficit, I've seen some research suggesting that there's a limit to how much fat we can metabolize when eating at a deficit - on the order of 30-something calories per pound of body fat per day, IIRC. (Did I bookmark that cite? Nah, that would require my being organized.)

    After that, we're likely to burn lean tissue in addition to fat, and that would be a reason to avoid a vlcd that led to high weight loss rates.

    A presumed limited ability to metabolize fat is the basis for various rules of thumb like "don't lose more than 1% of your body weight per week" or "cut your loss rate to 1 pound a week at X pounds before goal, and 0.5 pounds at Y pounds before goal". (I've seen X=50, Y=25; or X=25, Y=10.) I think both of those will end up having a safety margin built in for most people.

    ETA: Found a link to one of the studies (well, to the abstract - full text is behind a paywall, unless you have institutional access). It's sciencedirect.com/science/article/pii/S0022519304004175

    Thanks, this is exactly the kind of thing I was wanting to see! So, according to this theory, the maximum fat oxidation rate is 290KJ/KG fat per day. Going through the conversions, you could figure out the breaking point of where you would start losing lean body mass.

    For a 200 lb person with 25% BF they would have 22.7kg fat. Their maximum rate would be (22.7kg*290KJ/KG) 6,583 KJ/day which is a limiting rate of 1,572 calories per day from fat stores. That comes out to a limiting fat loss rate of about 3 lb/wk.

    So if their BMR was 2000 and TDEE was 2400, if they ate 1200 calories, the extra 1200 calories to reach TDEE from fat stores is still within the limiting rate.

    Assuming that they were able to get proper nutrition within those limited number of calories (big assumption), I would not think they would have any trouble burning fat stores to support BMR functions...

    You misinterpreted as I never mentioned fat stores or weight at all in regards to BMR. What I said was its not healthy long term to eat below BMR because that is the amount your body requires for basic function; breathing, heart beat, etc. You need to give you body adequate fuel to stay alive regardless of weight or weight goals.

    ok... but, solely from an energy standpoint, as long as you have fat stores available... wouldn't you have the energy you need for your BMR functions?

    Sure for awhile you would dig into fat stores along with lean muscle mass but eventually you would starve. You seem to be implying that starvation can't happen until your body has no fat left to use at all. That isn't true. As someone recovered from an eating disorder I am personaly very aware of what happens when you don't eat enough to fuel basic function. I suffered gallstones, kidney issues, muscle loss, fainting spells, blood pressure issues, and hair loss. These health risks are very real if you are not eating enough to support proper basic body function.

    Why are you so dead set on proving that eating below BMR long term is healthy? Since my sole point originally was the health risk and you continue to argue it I have to assume that you believe there isn't a health risk there. It's concerning.

    I'll agree with that statement. The fat will make up the remaining energy, which is what I have been saying. If you are getting adequate nutrients and some exercise, you really won't even lose that much lean mass while you are overweight. Once you get VERY lean (<5% for men and 13% for females), is where the issues you described become very real. Most people in a weight loss forum don't have to worry much about that for quite a while.

    I can definitely see where someone with your background would have a different perspective and be sensitive to the subject, but I would also bet that when you were dealing with your eating disorder that, not only were you not getting enough energy, but you also were not getting proper nutrients. That is the entire point I am trying to make, which is what the OP originally asked (Where does that 1200 number come from?) - the number comes from it is the number of calories the food contains that an average person eating a BALANCED diet needs to get proper nutrients. Once you calculate the calories of the protein minimums, fat minimums, and tag along carbs, it comes out to about 1200 calories for most people. Energy has very little to do with it until you get very lean; aka have plenty of available fat stores.

    Finally, for the record, I'm not trying to prove that VLCD's are healthy. In fact, in almost every post I have said that I don't recommend them. I was simply answering the question that was asked and I asked you for clarification/supporting info on your statement.

    GauchoMark, I'm not quoting you to disagree with you specifically, but rather just picking up a substantive post (yours) in this line of discussion to make clear what sub-thread I intend to be opining about.

    I'd be tempted to assume that VLCD deficits, even below BMR, could be made up from fat stores (limits on fat metabolism from previous cites understood as limiting, of course).

    But then I keep tripping over stuff like this, with suggestions that it's not that simple: Metabolic and Behavioral Compensations in Response to Caloric Restriction: Implications for the Maintenance of Weight Loss.

    My main point here is not the main point of this study, but rather I'd call attention to figure 2, where losses of fat-free mass show up in each of the study arms, but more so in some than others - and not uniformly proportionate to total weight loss, either. (There are other studies showing similar things about loss of fat-free mass in calorie restriction that is not a VLCD. I link this one for reasons that may be more apparent below.)

    I grant that this particular study is small, and the people are non-obese, but the results do suggests some "costs" in lean body mass for calorie restrictions that are not even as extreme as a VLCD.

    Beyond the lean body mass issue, the apparent longer-term TDEE reduction, especially that unexplained by fat-free-mass loss, is something I think we would also want to be concerned about while losing weight. (I'd vote that most of us would prefer to have the results associated with the CR + EX study arm, if we have to pick one. ;) )

    For those who don't love reading research papers, there's a good blog post here about this study, though the blog comes at it from the TDEE standpoint (logically enough, since that's the main point of the study): myfitnesspal.com/blog/heybales?month=201401

    But heck, I'm not a scientist . . . .
  • CeeBeeSlim
    CeeBeeSlim Posts: 1,297 Member
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    Thanks for the explanations. These all make sense. I'm also realizing I can make a measurable difference by upping my NEAT - finding ways to do ANY extra movement - dancing, leg lifts, twists, while brushing teeth, washing dishes, etc?! Is this correct? A measureable difference?
  • AnnPT77
    AnnPT77 Posts: 32,838 Member
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    CeeBeeSlim wrote: »
    Thanks for the explanations. These all make sense. I'm also realizing I can make a measurable difference by upping my NEAT - finding ways to do ANY extra movement - dancing, leg lifts, twists, while brushing teeth, washing dishes, etc?! Is this correct? A measureable difference?

    Good insight. Yes, it's possible. That's what the popular-press "take the stairs", "park further from the store" stuff is about, too.

    It's difficult to estimate what the calorie impact of NEAT changes (up or down) will be, but if you strive for consistency, you'll see the result in your weight loss rate & can adjust accordingly.
  • kimny72
    kimny72 Posts: 16,013 Member
    edited January 2017
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    CeeBeeSlim wrote: »
    Thanks for the explanations. These all make sense. I'm also realizing I can make a measurable difference by upping my NEAT - finding ways to do ANY extra movement - dancing, leg lifts, twists, while brushing teeth, washing dishes, etc?! Is this correct? A measureable difference?

    Yes :) I try to get 8K steps (total, not just as planned exercise), and my walking usually gets me an extra 200 cals, and based on my weight loss/ maintenance results over the last few years suggest it's accurate. The specifics will be different for everyone, but 200 cals is doable and can make a big difference when you are dealing with low calories!
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
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    GauchoMark wrote: »
    lemurcat12 wrote: »
    SCoil123 wrote: »
    Why are you so dead set on proving that eating below BMR long term is healthy? Since my sole point originally was the health risk and you continue to argue it I have to assume that you believe there isn't a health risk there. It's concerning.

    There's a health risk from undereating, but it isn't about BMR as people often claim (that's a myth--your body can't tell if you are under or over BMR unless you are actually immobile) or eating 1200 for a period of time. I think that's all GauchoMark is pointing out.

    Thanks, that is more or less the point. The 1200 calories has little to do with BMR and more to do with nutritional needs.

    Yes, but I'll suggest that BMR is a better proxy for nutritional needs than a blanket number (of 1200 or whatever other number you want to pick) because it factors in that taller/more muscular people need more nutrients than smaller people.

    Neither one is a very good estimate, as they ignore fat vs. lean mass (depending on how the BMR is calculated, of course) and activity. The 10xgoal is also terrible.

    One issue is that the BMR rule is often stated as if something bad happened below BMR when your body cannot tell it is below BMR. BMR is a hypothetical number -- and an estimate of that, also -- when you would lose weight if completely immobile. That's it.

    My estimated BMR using the MFP way (Mifflin St Jeor), when I started here (5'3 and 200) was about 1530. However, if you used Katch-McArdle and assumed 45% BF (which is reasonable to low given that my lean mass is about 95 now), it would have been 1450.

    With M-StJ, sedentary TDEE is about 1830, and with K-McA, sedentary TDEE is about 1740.

    So if my real BMR was 1450, but I assumed 1530 and was sedentary, I'd be losing less than a half lb/week, despite being obese. That aside, clearly a goal of 1-2 lb is appropriate at 5'3 and 200, so if sedentary eating 1200 would be perfectly appropriate, even though that's under BMR.

    (I would advise not being sedentary, of course, but the fact is that if someone is and has a decent amount to lose, they will normally be quite reasonably eating under BMR without that being a particularly deep deficit.)

    I personally think the best way to judge it is to look at what the actual deficit is, given amount to lose.
  • jemhh
    jemhh Posts: 14,261 Member
    edited January 2017
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    lemurcat12 wrote: »
    GauchoMark wrote: »
    lemurcat12 wrote: »
    SCoil123 wrote: »
    Why are you so dead set on proving that eating below BMR long term is healthy? Since my sole point originally was the health risk and you continue to argue it I have to assume that you believe there isn't a health risk there. It's concerning.

    There's a health risk from undereating, but it isn't about BMR as people often claim (that's a myth--your body can't tell if you are under or over BMR unless you are actually immobile) or eating 1200 for a period of time. I think that's all GauchoMark is pointing out.

    Thanks, that is more or less the point. The 1200 calories has little to do with BMR and more to do with nutritional needs.

    Yes, but I'll suggest that BMR is a better proxy for nutritional needs than a blanket number (of 1200 or whatever other number you want to pick) because it factors in that taller/more muscular people need more nutrients than smaller people.

    Neither one is a very good estimate, as they ignore fat vs. lean mass (depending on how the BMR is calculated, of course) and activity. The 10xgoal is also terrible.

    One issue is that the BMR rule is often stated as if something bad happened below BMR when your body cannot tell it is below BMR. BMR is a hypothetical number -- and an estimate of that, also -- when you would lose weight if completely immobile. That's it.

    My estimated BMR using the MFP way (Mifflin St Jeor), when I started here (5'3 and 200) was about 1530. However, if you used Katch-McArdle and assumed 45% BF (which is reasonable to low given that my lean mass is about 95 now), it would have been 1450.

    With M-StJ, sedentary TDEE is about 1830, and with K-McA, sedentary TDEE is about 1740.

    So if my real BMR was 1450, but I assumed 1530 and was sedentary, I'd be losing less than a half lb/week, despite being obese. That aside, clearly a goal of 1-2 lb is appropriate at 5'3 and 200, so if sedentary eating 1200 would be perfectly appropriate, even though that's under BMR.

    (I would advise not being sedentary, of course, but the fact is that if someone is and has a decent amount to lose, they will normally be quite reasonably eating under BMR without that being a particularly deep deficit.)

    I personally think the best way to judge it is to look at what the actual deficit is, given amount to lose.

    I'm going to pop in here to beat my drum about a healthy lower limit for women. I've gone into this on many threads lately but the audience is a bit different on this one so I'll say it again.

    Studies are showing that when a woman's energy availability decrease to a level below 20-30 calories per kg of lean mass (9.6-13.6 calories per lb), her system starts to adapt. Note that these adaptations begin within days of eating like this. It doesn't take weeks or months. One of the big adaptations is that her reproductive system senses that now is not a good time to reproduce and she loses her period. Estrogen levels also decrease to a level where bone regeneration is stunted, which can mean bone loss leading to increased risk of stress fractures and even osteoporosis.

    Mathematic example:

    Example woman:
    140 lbs
    27% bodyweight
    102 lbs LBM
    13.6 x 102 lbs = 1387 net calories would be tipping point

    I quickly ran BMR calcs for women who were 60 years old, 5' tall, and 140 lbs and then 20 years old, 5'9" tall, and 140 lbs in order to get a range. I got 1127 for the first woman and 1469 for the second woman. In one instance, using BMR as a minimum could lead to the problems mentioned above (obviously not lack of period since a 60 yo woman would be past that but bone issues for sure) and in one it would be an okay minimum. But BF% would be better to use, the problem of course being that even that number is an estimate which can be off 10% at times. So maybe do the calc (for women) at BF% plus 10% in order to be conservative.

    Articles about this in spoiler tags below.
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    edited January 2017
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    jemhh wrote: »
    lemurcat12 wrote: »
    GauchoMark wrote: »
    lemurcat12 wrote: »
    SCoil123 wrote: »
    Why are you so dead set on proving that eating below BMR long term is healthy? Since my sole point originally was the health risk and you continue to argue it I have to assume that you believe there isn't a health risk there. It's concerning.

    There's a health risk from undereating, but it isn't about BMR as people often claim (that's a myth--your body can't tell if you are under or over BMR unless you are actually immobile) or eating 1200 for a period of time. I think that's all GauchoMark is pointing out.

    Thanks, that is more or less the point. The 1200 calories has little to do with BMR and more to do with nutritional needs.

    Yes, but I'll suggest that BMR is a better proxy for nutritional needs than a blanket number (of 1200 or whatever other number you want to pick) because it factors in that taller/more muscular people need more nutrients than smaller people.

    Neither one is a very good estimate, as they ignore fat vs. lean mass (depending on how the BMR is calculated, of course) and activity. The 10xgoal is also terrible.

    One issue is that the BMR rule is often stated as if something bad happened below BMR when your body cannot tell it is below BMR. BMR is a hypothetical number -- and an estimate of that, also -- when you would lose weight if completely immobile. That's it.

    My estimated BMR using the MFP way (Mifflin St Jeor), when I started here (5'3 and 200) was about 1530. However, if you used Katch-McArdle and assumed 45% BF (which is reasonable to low given that my lean mass is about 95 now), it would have been 1450.

    With M-StJ, sedentary TDEE is about 1830, and with K-McA, sedentary TDEE is about 1740.

    So if my real BMR was 1450, but I assumed 1530 and was sedentary, I'd be losing less than a half lb/week, despite being obese. That aside, clearly a goal of 1-2 lb is appropriate at 5'3 and 200, so if sedentary eating 1200 would be perfectly appropriate, even though that's under BMR.

    (I would advise not being sedentary, of course, but the fact is that if someone is and has a decent amount to lose, they will normally be quite reasonably eating under BMR without that being a particularly deep deficit.)

    I personally think the best way to judge it is to look at what the actual deficit is, given amount to lose.

    I'm going to pop in here to beat my drum about a healthy lower limit for women. I've gone into this on many threads lately but the audience is a bit different on this one so I'll say it again.

    Studies are showing that when a woman's energy availability decrease to a level below 20-30 calories per kg of lean mass (9.6-13.6 calories per lb), her system starts to adapt. Note that these adaptations begin within days of eating like this. It doesn't take weeks or months. One of the big adaptations is that her reproductive system senses that now is not a good time to reproduce and she loses your period. Estrogen levels also decrease to a level where bone regeneration is stunted, which can mean bone loss leading to increased risk of stress fractures and even osteoporosis.

    Mathematic example:

    Example woman:
    140 lbs
    27% bodyweight
    102 lbs LBM
    13.6 x 102 lbs = 1387 net calories would be tipping point

    I quickly ran BMR calcs for women who were 60 years old, 5' tall, and 140 lbs and then 20 years old, 5'9" tall, and 140 lbs in order to get a range. I got 1127 for the first woman and 1469 for the second woman. In one instance, using BMR as a minimum could lead to the problems mentioned above (obviously not lack of period since a 60 yo woman would be past that but bone issues for sure) and in one it would be an okay minimum. But BF% would be better to use, the problem of course being that even that number is an estimate which can be off 10% at times. So maybe do the calc (for women) at BF% plus 10% in order to be conservative.

    That's very interesting.

    Using myself, I get 95 LBM (DEXA) so between 864 and 1295 (wide range). My BMR is around 1300 by BF% (Katch-McArdle). Assuming LBM was higher (around 105) when I was obese, it would have been 955-1431 (BMR was higher, as noted above, although similar to the high end using K-McA). I netted 1250 for some time, no problem, when losing (and lost consistent with that number, so doubt I was eating more than I think).

    Relevant thing to note with the Lyle McDonald piece is that it's not total calories but gross calories -- minus exercise. This is worth noting because it's normally sedentary people who can reasonably eat below BMR. If Lyle is right, then it would be a problem for someone exercising vigorously to eat even too low but well above BMR, which is of course common sense and gets back to the idea that one should look at deficit from TDEE and total amount left to lose.

    My kneejerk suspicion is that it's less harmful to eat low when you have more weight to lose (although the Lyle article doesn't say so). The Pub Med was about female athletes. Would be interested in more information/cites.
  • GauchoMark
    GauchoMark Posts: 1,804 Member
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    AnnPT77 wrote: »
    GauchoMark wrote: »
    SCoil123 wrote: »
    GauchoMark wrote: »
    SCoil123 wrote: »
    GauchoMark wrote: »
    SCoil123 wrote: »
    GauchoMark wrote: »
    It must also be noted that intake isn't just about nutrients. Sure they should be the primary concern but calories purely from an energy standpoint are hella important too. Your body needs those to fuel basic bodily functions, it can't get all it needs from stored fat every day. Eating too little fat will impact hormone function and ability to absorb those precious tricky to hit on a low intake nutrients.

    Reducing body weight is important, retaining health and lean body mass is more important.

    SCoil123 wrote: »
    For me I'm 5'7" and work out daily which includes a few sessions of Insanity and weight lifting. 1200 cals would not be healthy for me. I personally don't like the idea of eating below BMR and believe long term this can be dangerous for anyone though, since that is the number your body requires for basic functions.

    While I don't recommend anyone to go sub 1200 for very long if they can lose weight other ways, I don't think these statements are correct. If you are truly getting sufficient essential nutrients and micro nutrients, the entire purpose of fat deposits are to supply energy. These statements are implying that for some reason, when we eat less than we burn, that our bodies lose the ability to oxidize fat to make up the energy deficit.

    Do either of you have anything besides opinion to back this up? I'd like to see the mechanism that would lead us to the inability to convert fat deposits to energy in times of vlc intake.

    Your BMR (Basal Metabolic Rate) is an estimate of how many calories you'd burn if you were to do nothing but rest for 24 hours. It represents the minimum amount of energy needed to keep your body functioning, including breathing and keeping your heart beating.

    I never implied that when you eat less than you burn you lose the ability to lose fat. What I said was that I do not believe it is healthy long term to eat below BMR because that is what your body needs to maintain basic function. I'm honestly not sure how you made the leap to preventing fat burn from that. I never even mentioned weight loss or fat in my reasoning as it was purely a health concern I was noting.

    The result of not eating enough to fuel basic functions like breathing and your heart beat would actually be death - not the inability to burn fat

    I understand BMR. However, energy is energy whether you get it from food or fat stores. You said that you think that if you don't EAT enough energy, that you would drop below the BMR energy requirement and that is unhealthy/dangerous. That implies that the energy from fat stores would not be used to make up the difference. Maybe that is not what you meant, but that is what I read.
    AnnPT77 wrote: »
    GauchoMark wrote: »
    It must also be noted that intake isn't just about nutrients. Sure they should be the primary concern but calories purely from an energy standpoint are hella important too. Your body needs those to fuel basic bodily functions, it can't get all it needs from stored fat every day. Eating too little fat will impact hormone function and ability to absorb those precious tricky to hit on a low intake nutrients.

    Reducing body weight is important, retaining health and lean body mass is more important.

    SCoil123 wrote: »
    For me I'm 5'7" and work out daily which includes a few sessions of Insanity and weight lifting. 1200 cals would not be healthy for me. I personally don't like the idea of eating below BMR and believe long term this can be dangerous for anyone though, since that is the number your body requires for basic functions.

    While I don't recommend anyone to go sub 1200 for very long if they can lose weight other ways, I don't think these statements are correct. If you are truly getting sufficient essential nutrients and micro nutrients, the entire purpose of fat deposits are to supply energy. These statements are implying that for some reason, when we eat less than we burn, that our bodies lose the ability to oxidize fat to make up the energy deficit.

    Do either of you have anything besides opinion to back this up? I'd like to see the mechanism that would lead us to the inability to convert fat deposits to energy in times of vlc intake.

    While I know of no mechanism for the inability to convert fat to energy while in calorie deficit, I've seen some research suggesting that there's a limit to how much fat we can metabolize when eating at a deficit - on the order of 30-something calories per pound of body fat per day, IIRC. (Did I bookmark that cite? Nah, that would require my being organized.)

    After that, we're likely to burn lean tissue in addition to fat, and that would be a reason to avoid a vlcd that led to high weight loss rates.

    A presumed limited ability to metabolize fat is the basis for various rules of thumb like "don't lose more than 1% of your body weight per week" or "cut your loss rate to 1 pound a week at X pounds before goal, and 0.5 pounds at Y pounds before goal". (I've seen X=50, Y=25; or X=25, Y=10.) I think both of those will end up having a safety margin built in for most people.

    ETA: Found a link to one of the studies (well, to the abstract - full text is behind a paywall, unless you have institutional access). It's sciencedirect.com/science/article/pii/S0022519304004175

    Thanks, this is exactly the kind of thing I was wanting to see! So, according to this theory, the maximum fat oxidation rate is 290KJ/KG fat per day. Going through the conversions, you could figure out the breaking point of where you would start losing lean body mass.

    For a 200 lb person with 25% BF they would have 22.7kg fat. Their maximum rate would be (22.7kg*290KJ/KG) 6,583 KJ/day which is a limiting rate of 1,572 calories per day from fat stores. That comes out to a limiting fat loss rate of about 3 lb/wk.

    So if their BMR was 2000 and TDEE was 2400, if they ate 1200 calories, the extra 1200 calories to reach TDEE from fat stores is still within the limiting rate.

    Assuming that they were able to get proper nutrition within those limited number of calories (big assumption), I would not think they would have any trouble burning fat stores to support BMR functions...

    You misinterpreted as I never mentioned fat stores or weight at all in regards to BMR. What I said was its not healthy long term to eat below BMR because that is the amount your body requires for basic function; breathing, heart beat, etc. You need to give you body adequate fuel to stay alive regardless of weight or weight goals.

    ok... but, solely from an energy standpoint, as long as you have fat stores available... wouldn't you have the energy you need for your BMR functions?

    Sure for awhile you would dig into fat stores along with lean muscle mass but eventually you would starve. You seem to be implying that starvation can't happen until your body has no fat left to use at all. That isn't true. As someone recovered from an eating disorder I am personaly very aware of what happens when you don't eat enough to fuel basic function. I suffered gallstones, kidney issues, muscle loss, fainting spells, blood pressure issues, and hair loss. These health risks are very real if you are not eating enough to support proper basic body function.

    Why are you so dead set on proving that eating below BMR long term is healthy? Since my sole point originally was the health risk and you continue to argue it I have to assume that you believe there isn't a health risk there. It's concerning.

    I'll agree with that statement. The fat will make up the remaining energy, which is what I have been saying. If you are getting adequate nutrients and some exercise, you really won't even lose that much lean mass while you are overweight. Once you get VERY lean (<5% for men and 13% for females), is where the issues you described become very real. Most people in a weight loss forum don't have to worry much about that for quite a while.

    I can definitely see where someone with your background would have a different perspective and be sensitive to the subject, but I would also bet that when you were dealing with your eating disorder that, not only were you not getting enough energy, but you also were not getting proper nutrients. That is the entire point I am trying to make, which is what the OP originally asked (Where does that 1200 number come from?) - the number comes from it is the number of calories the food contains that an average person eating a BALANCED diet needs to get proper nutrients. Once you calculate the calories of the protein minimums, fat minimums, and tag along carbs, it comes out to about 1200 calories for most people. Energy has very little to do with it until you get very lean; aka have plenty of available fat stores.

    Finally, for the record, I'm not trying to prove that VLCD's are healthy. In fact, in almost every post I have said that I don't recommend them. I was simply answering the question that was asked and I asked you for clarification/supporting info on your statement.

    GauchoMark, I'm not quoting you to disagree with you specifically, but rather just picking up a substantive post (yours) in this line of discussion to make clear what sub-thread I intend to be opining about.

    I'd be tempted to assume that VLCD deficits, even below BMR, could be made up from fat stores (limits on fat metabolism from previous cites understood as limiting, of course).

    But then I keep tripping over stuff like this, with suggestions that it's not that simple: Metabolic and Behavioral Compensations in Response to Caloric Restriction: Implications for the Maintenance of Weight Loss.

    My main point here is not the main point of this study, but rather I'd call attention to figure 2, where losses of fat-free mass show up in each of the study arms, but more so in some than others - and not uniformly proportionate to total weight loss, either. (There are other studies showing similar things about loss of fat-free mass in calorie restriction that is not a VLCD. I link this one for reasons that may be more apparent below.)

    I grant that this particular study is small, and the people are non-obese, but the results do suggests some "costs" in lean body mass for calorie restrictions that are not even as extreme as a VLCD.

    Beyond the lean body mass issue, the apparent longer-term TDEE reduction, especially that unexplained by fat-free-mass loss, is something I think we would also want to be concerned about while losing weight. (I'd vote that most of us would prefer to have the results associated with the CR + EX study arm, if we have to pick one. ;) )

    For those who don't love reading research papers, there's a good blog post here about this study, though the blog comes at it from the TDEE standpoint (logically enough, since that's the main point of the study): myfitnesspal.com/blog/heybales?month=201401

    But heck, I'm not a scientist . . . .

    @AnnPT77 thanks again for the link. It is pretty commonly accepted that as a rule of thumb that under a caloric deficit that there will be some FFM loss. The question is not "if" but rather "how much". There is also quite a bit of support for hormone levels changing and metabolic adaptation under caloric restriction.

    Some people think it is possible to do a VLCD without any FFM loss. While I certainly think there are things you can do to preserve FFM, I am still not sure that I believe that you can prevent it. If you can, it would definitely not be something you do by accident - it would be a tediously controlled diet and exercise program.

    One issue I see (or didn't catch) in the study you posted was what did they eat? They restricted their diet, but it didn't say how or if each group did it the same way. That would have been very interesting to see.
  • jemhh
    jemhh Posts: 14,261 Member
    edited January 2017
    Options
    lemurcat12 wrote: »
    jemhh wrote: »
    lemurcat12 wrote: »
    GauchoMark wrote: »
    lemurcat12 wrote: »
    SCoil123 wrote: »
    Why are you so dead set on proving that eating below BMR long term is healthy? Since my sole point originally was the health risk and you continue to argue it I have to assume that you believe there isn't a health risk there. It's concerning.

    There's a health risk from undereating, but it isn't about BMR as people often claim (that's a myth--your body can't tell if you are under or over BMR unless you are actually immobile) or eating 1200 for a period of time. I think that's all GauchoMark is pointing out.

    Thanks, that is more or less the point. The 1200 calories has little to do with BMR and more to do with nutritional needs.

    Yes, but I'll suggest that BMR is a better proxy for nutritional needs than a blanket number (of 1200 or whatever other number you want to pick) because it factors in that taller/more muscular people need more nutrients than smaller people.

    Neither one is a very good estimate, as they ignore fat vs. lean mass (depending on how the BMR is calculated, of course) and activity. The 10xgoal is also terrible.

    One issue is that the BMR rule is often stated as if something bad happened below BMR when your body cannot tell it is below BMR. BMR is a hypothetical number -- and an estimate of that, also -- when you would lose weight if completely immobile. That's it.

    My estimated BMR using the MFP way (Mifflin St Jeor), when I started here (5'3 and 200) was about 1530. However, if you used Katch-McArdle and assumed 45% BF (which is reasonable to low given that my lean mass is about 95 now), it would have been 1450.

    With M-StJ, sedentary TDEE is about 1830, and with K-McA, sedentary TDEE is about 1740.

    So if my real BMR was 1450, but I assumed 1530 and was sedentary, I'd be losing less than a half lb/week, despite being obese. That aside, clearly a goal of 1-2 lb is appropriate at 5'3 and 200, so if sedentary eating 1200 would be perfectly appropriate, even though that's under BMR.

    (I would advise not being sedentary, of course, but the fact is that if someone is and has a decent amount to lose, they will normally be quite reasonably eating under BMR without that being a particularly deep deficit.)

    I personally think the best way to judge it is to look at what the actual deficit is, given amount to lose.

    I'm going to pop in here to beat my drum about a healthy lower limit for women. I've gone into this on many threads lately but the audience is a bit different on this one so I'll say it again.

    Studies are showing that when a woman's energy availability decrease to a level below 20-30 calories per kg of lean mass (9.6-13.6 calories per lb), her system starts to adapt. Note that these adaptations begin within days of eating like this. It doesn't take weeks or months. One of the big adaptations is that her reproductive system senses that now is not a good time to reproduce and she loses your period. Estrogen levels also decrease to a level where bone regeneration is stunted, which can mean bone loss leading to increased risk of stress fractures and even osteoporosis.

    Mathematic example:

    Example woman:
    140 lbs
    27% bodyweight
    102 lbs LBM
    13.6 x 102 lbs = 1387 net calories would be tipping point

    I quickly ran BMR calcs for women who were 60 years old, 5' tall, and 140 lbs and then 20 years old, 5'9" tall, and 140 lbs in order to get a range. I got 1127 for the first woman and 1469 for the second woman. In one instance, using BMR as a minimum could lead to the problems mentioned above (obviously not lack of period since a 60 yo woman would be past that but bone issues for sure) and in one it would be an okay minimum. But BF% would be better to use, the problem of course being that even that number is an estimate which can be off 10% at times. So maybe do the calc (for women) at BF% plus 10% in order to be conservative.

    That's very interesting.

    Using myself, I get 95 LBM (DEXA) so between 864 and 1295 (wide range). My BMR is around 1300 by BF% (Katch-McArdle). Assuming LBM was higher (around 105) when I was obese, it would have been 955-1431 (BMR was higher, as noted above, although similar to the high end using K-McA). I netted 1250 for some time, no problem, when losing (and lost consistent with that number, so doubt I was eating more than I think).

    Relevant thing to note with the Lyle McDonald piece is that it's not total calories but gross calories -- minus exercise. This is worth noting because it's normally sedentary people who can reasonably eat below BMR. If Lyle is right, then it would be a problem for someone exercising vigorously to eat even too low but well above BMR, which is of course common sense and gets back to the idea that one should look at deficit from TDEE and total amount left to lose.

    My kneejerk suspicion is that it's less harmful to eat low when you have more weight to lose (although the Lyle article doesn't say so). The Pub Med was about female athletes. Would be interested in more information/cites.

    I can say that last year I ate above BMR (1650 minimum but very often higher), overexercised, and ended up with problems. I had a bone scan done so I have a baseline now but, unfortunately, have nothing to compare it to from earlier in my life. So who knows what damage I did. I do wonder about the difference between fairly fit individuals and people who are at that starting sedentary/obese point. When I first started dieting I didn't count calories so I don't know how much I was eating but I wouldn't be surprised if at least for a short time it was low enough to go under BMR and the tipping point mentioned above.
  • GauchoMark
    GauchoMark Posts: 1,804 Member
    Options
    jemhh wrote: »
    lemurcat12 wrote: »
    GauchoMark wrote: »
    lemurcat12 wrote: »
    SCoil123 wrote: »
    Why are you so dead set on proving that eating below BMR long term is healthy? Since my sole point originally was the health risk and you continue to argue it I have to assume that you believe there isn't a health risk there. It's concerning.

    There's a health risk from undereating, but it isn't about BMR as people often claim (that's a myth--your body can't tell if you are under or over BMR unless you are actually immobile) or eating 1200 for a period of time. I think that's all GauchoMark is pointing out.

    Thanks, that is more or less the point. The 1200 calories has little to do with BMR and more to do with nutritional needs.

    Yes, but I'll suggest that BMR is a better proxy for nutritional needs than a blanket number (of 1200 or whatever other number you want to pick) because it factors in that taller/more muscular people need more nutrients than smaller people.

    Neither one is a very good estimate, as they ignore fat vs. lean mass (depending on how the BMR is calculated, of course) and activity. The 10xgoal is also terrible.

    One issue is that the BMR rule is often stated as if something bad happened below BMR when your body cannot tell it is below BMR. BMR is a hypothetical number -- and an estimate of that, also -- when you would lose weight if completely immobile. That's it.

    My estimated BMR using the MFP way (Mifflin St Jeor), when I started here (5'3 and 200) was about 1530. However, if you used Katch-McArdle and assumed 45% BF (which is reasonable to low given that my lean mass is about 95 now), it would have been 1450.

    With M-StJ, sedentary TDEE is about 1830, and with K-McA, sedentary TDEE is about 1740.

    So if my real BMR was 1450, but I assumed 1530 and was sedentary, I'd be losing less than a half lb/week, despite being obese. That aside, clearly a goal of 1-2 lb is appropriate at 5'3 and 200, so if sedentary eating 1200 would be perfectly appropriate, even though that's under BMR.

    (I would advise not being sedentary, of course, but the fact is that if someone is and has a decent amount to lose, they will normally be quite reasonably eating under BMR without that being a particularly deep deficit.)

    I personally think the best way to judge it is to look at what the actual deficit is, given amount to lose.

    I'm going to pop in here to beat my drum about a healthy lower limit for women. I've gone into this on many threads lately but the audience is a bit different on this one so I'll say it again.

    Studies are showing that when a woman's energy availability decrease to a level below 20-30 calories per kg of lean mass (9.6-13.6 calories per lb), her system starts to adapt. Note that these adaptations begin within days of eating like this. It doesn't take weeks or months. One of the big adaptations is that her reproductive system senses that now is not a good time to reproduce and she loses her period. Estrogen levels also decrease to a level where bone regeneration is stunted, which can mean bone loss leading to increased risk of stress fractures and even osteoporosis.

    Mathematic example:

    Example woman:
    140 lbs
    27% bodyweight
    102 lbs LBM
    13.6 x 102 lbs = 1387 net calories would be tipping point

    I quickly ran BMR calcs for women who were 60 years old, 5' tall, and 140 lbs and then 20 years old, 5'9" tall, and 140 lbs in order to get a range. I got 1127 for the first woman and 1469 for the second woman. In one instance, using BMR as a minimum could lead to the problems mentioned above (obviously not lack of period since a 60 yo woman would be past that but bone issues for sure) and in one it would be an okay minimum. But BF% would be better to use, the problem of course being that even that number is an estimate which can be off 10% at times. So maybe do the calc (for women) at BF% plus 10% in order to be conservative.

    Articles about this in spoiler tags below.

    Interesting info. I wonder if Lyle's full book has those number for men as well, as the hormone changes happen to us too (just not as drastic).

    One thing to point out is there are a lot of studies that show that dropped hormone levels due to caloric restriction bounce back to normal levels rather quickly once calories are increased. So, that occasional "cheat day" helps bring them back up.
  • SusanMFindlay
    SusanMFindlay Posts: 1,804 Member
    edited January 2017
    Options
    CeeBeeSlim wrote: »
    Thanks for the explanations. These all make sense. I'm also realizing I can make a measurable difference by upping my NEAT - finding ways to do ANY extra movement - dancing, leg lifts, twists, while brushing teeth, washing dishes, etc?! Is this correct? A measureable difference?

    Yes. About 50% of my daily calorie burn is from NEAT (BMR 1400ish; daily calorie burn on non-workout day 2700ish). I realize that I am an outlier in that respect (and that's almost 20,000 steps/day worth of NEAT), but it is very possible.
  • CeeBeeSlim
    CeeBeeSlim Posts: 1,297 Member
    Options
    @SusanMFindlay Wow. I'm inspired! I may have to change my member name to The Whirling Dervish! ;)
  • AnnPT77
    AnnPT77 Posts: 32,838 Member
    edited January 2017
    Options
    GauchoMark wrote: »
    AnnPT77 wrote: »
    GauchoMark wrote: »
    SCoil123 wrote: »
    GauchoMark wrote: »
    SCoil123 wrote: »
    GauchoMark wrote: »
    SCoil123 wrote: »
    GauchoMark wrote: »
    It must also be noted that intake isn't just about nutrients. Sure they should be the primary concern but calories purely from an energy standpoint are hella important too. Your body needs those to fuel basic bodily functions, it can't get all it needs from stored fat every day. Eating too little fat will impact hormone function and ability to absorb those precious tricky to hit on a low intake nutrients.

    Reducing body weight is important, retaining health and lean body mass is more important.

    SCoil123 wrote: »
    For me I'm 5'7" and work out daily which includes a few sessions of Insanity and weight lifting. 1200 cals would not be healthy for me. I personally don't like the idea of eating below BMR and believe long term this can be dangerous for anyone though, since that is the number your body requires for basic functions.

    While I don't recommend anyone to go sub 1200 for very long if they can lose weight other ways, I don't think these statements are correct. If you are truly getting sufficient essential nutrients and micro nutrients, the entire purpose of fat deposits are to supply energy. These statements are implying that for some reason, when we eat less than we burn, that our bodies lose the ability to oxidize fat to make up the energy deficit.

    Do either of you have anything besides opinion to back this up? I'd like to see the mechanism that would lead us to the inability to convert fat deposits to energy in times of vlc intake.

    Your BMR (Basal Metabolic Rate) is an estimate of how many calories you'd burn if you were to do nothing but rest for 24 hours. It represents the minimum amount of energy needed to keep your body functioning, including breathing and keeping your heart beating.

    I never implied that when you eat less than you burn you lose the ability to lose fat. What I said was that I do not believe it is healthy long term to eat below BMR because that is what your body needs to maintain basic function. I'm honestly not sure how you made the leap to preventing fat burn from that. I never even mentioned weight loss or fat in my reasoning as it was purely a health concern I was noting.

    The result of not eating enough to fuel basic functions like breathing and your heart beat would actually be death - not the inability to burn fat

    I understand BMR. However, energy is energy whether you get it from food or fat stores. You said that you think that if you don't EAT enough energy, that you would drop below the BMR energy requirement and that is unhealthy/dangerous. That implies that the energy from fat stores would not be used to make up the difference. Maybe that is not what you meant, but that is what I read.
    AnnPT77 wrote: »
    GauchoMark wrote: »
    It must also be noted that intake isn't just about nutrients. Sure they should be the primary concern but calories purely from an energy standpoint are hella important too. Your body needs those to fuel basic bodily functions, it can't get all it needs from stored fat every day. Eating too little fat will impact hormone function and ability to absorb those precious tricky to hit on a low intake nutrients.

    Reducing body weight is important, retaining health and lean body mass is more important.

    SCoil123 wrote: »
    For me I'm 5'7" and work out daily which includes a few sessions of Insanity and weight lifting. 1200 cals would not be healthy for me. I personally don't like the idea of eating below BMR and believe long term this can be dangerous for anyone though, since that is the number your body requires for basic functions.

    While I don't recommend anyone to go sub 1200 for very long if they can lose weight other ways, I don't think these statements are correct. If you are truly getting sufficient essential nutrients and micro nutrients, the entire purpose of fat deposits are to supply energy. These statements are implying that for some reason, when we eat less than we burn, that our bodies lose the ability to oxidize fat to make up the energy deficit.

    Do either of you have anything besides opinion to back this up? I'd like to see the mechanism that would lead us to the inability to convert fat deposits to energy in times of vlc intake.

    While I know of no mechanism for the inability to convert fat to energy while in calorie deficit, I've seen some research suggesting that there's a limit to how much fat we can metabolize when eating at a deficit - on the order of 30-something calories per pound of body fat per day, IIRC. (Did I bookmark that cite? Nah, that would require my being organized.)

    After that, we're likely to burn lean tissue in addition to fat, and that would be a reason to avoid a vlcd that led to high weight loss rates.

    A presumed limited ability to metabolize fat is the basis for various rules of thumb like "don't lose more than 1% of your body weight per week" or "cut your loss rate to 1 pound a week at X pounds before goal, and 0.5 pounds at Y pounds before goal". (I've seen X=50, Y=25; or X=25, Y=10.) I think both of those will end up having a safety margin built in for most people.

    ETA: Found a link to one of the studies (well, to the abstract - full text is behind a paywall, unless you have institutional access). It's sciencedirect.com/science/article/pii/S0022519304004175

    Thanks, this is exactly the kind of thing I was wanting to see! So, according to this theory, the maximum fat oxidation rate is 290KJ/KG fat per day. Going through the conversions, you could figure out the breaking point of where you would start losing lean body mass.

    For a 200 lb person with 25% BF they would have 22.7kg fat. Their maximum rate would be (22.7kg*290KJ/KG) 6,583 KJ/day which is a limiting rate of 1,572 calories per day from fat stores. That comes out to a limiting fat loss rate of about 3 lb/wk.

    So if their BMR was 2000 and TDEE was 2400, if they ate 1200 calories, the extra 1200 calories to reach TDEE from fat stores is still within the limiting rate.

    Assuming that they were able to get proper nutrition within those limited number of calories (big assumption), I would not think they would have any trouble burning fat stores to support BMR functions...

    You misinterpreted as I never mentioned fat stores or weight at all in regards to BMR. What I said was its not healthy long term to eat below BMR because that is the amount your body requires for basic function; breathing, heart beat, etc. You need to give you body adequate fuel to stay alive regardless of weight or weight goals.

    ok... but, solely from an energy standpoint, as long as you have fat stores available... wouldn't you have the energy you need for your BMR functions?

    Sure for awhile you would dig into fat stores along with lean muscle mass but eventually you would starve. You seem to be implying that starvation can't happen until your body has no fat left to use at all. That isn't true. As someone recovered from an eating disorder I am personaly very aware of what happens when you don't eat enough to fuel basic function. I suffered gallstones, kidney issues, muscle loss, fainting spells, blood pressure issues, and hair loss. These health risks are very real if you are not eating enough to support proper basic body function.

    Why are you so dead set on proving that eating below BMR long term is healthy? Since my sole point originally was the health risk and you continue to argue it I have to assume that you believe there isn't a health risk there. It's concerning.

    I'll agree with that statement. The fat will make up the remaining energy, which is what I have been saying. If you are getting adequate nutrients and some exercise, you really won't even lose that much lean mass while you are overweight. Once you get VERY lean (<5% for men and 13% for females), is where the issues you described become very real. Most people in a weight loss forum don't have to worry much about that for quite a while.

    I can definitely see where someone with your background would have a different perspective and be sensitive to the subject, but I would also bet that when you were dealing with your eating disorder that, not only were you not getting enough energy, but you also were not getting proper nutrients. That is the entire point I am trying to make, which is what the OP originally asked (Where does that 1200 number come from?) - the number comes from it is the number of calories the food contains that an average person eating a BALANCED diet needs to get proper nutrients. Once you calculate the calories of the protein minimums, fat minimums, and tag along carbs, it comes out to about 1200 calories for most people. Energy has very little to do with it until you get very lean; aka have plenty of available fat stores.

    Finally, for the record, I'm not trying to prove that VLCD's are healthy. In fact, in almost every post I have said that I don't recommend them. I was simply answering the question that was asked and I asked you for clarification/supporting info on your statement.

    GauchoMark, I'm not quoting you to disagree with you specifically, but rather just picking up a substantive post (yours) in this line of discussion to make clear what sub-thread I intend to be opining about.

    I'd be tempted to assume that VLCD deficits, even below BMR, could be made up from fat stores (limits on fat metabolism from previous cites understood as limiting, of course).

    But then I keep tripping over stuff like this, with suggestions that it's not that simple: Metabolic and Behavioral Compensations in Response to Caloric Restriction: Implications for the Maintenance of Weight Loss.

    My main point here is not the main point of this study, but rather I'd call attention to figure 2, where losses of fat-free mass show up in each of the study arms, but more so in some than others - and not uniformly proportionate to total weight loss, either. (There are other studies showing similar things about loss of fat-free mass in calorie restriction that is not a VLCD. I link this one for reasons that may be more apparent below.)

    I grant that this particular study is small, and the people are non-obese, but the results do suggests some "costs" in lean body mass for calorie restrictions that are not even as extreme as a VLCD.

    Beyond the lean body mass issue, the apparent longer-term TDEE reduction, especially that unexplained by fat-free-mass loss, is something I think we would also want to be concerned about while losing weight. (I'd vote that most of us would prefer to have the results associated with the CR + EX study arm, if we have to pick one. ;) )

    For those who don't love reading research papers, there's a good blog post here about this study, though the blog comes at it from the TDEE standpoint (logically enough, since that's the main point of the study): myfitnesspal.com/blog/heybales?month=201401

    But heck, I'm not a scientist . . . .

    @AnnPT77 thanks again for the link. It is pretty commonly accepted that as a rule of thumb that under a caloric deficit that there will be some FFM loss. The question is not "if" but rather "how much". There is also quite a bit of support for hormone levels changing and metabolic adaptation under caloric restriction.

    Some people think it is possible to do a VLCD without any FFM loss. While I certainly think there are things you can do to preserve FFM, I am still not sure that I believe that you can prevent it. If you can, it would definitely not be something you do by accident - it would be a tediously controlled diet and exercise program.

    One issue I see (or didn't catch) in the study you posted was what did they eat? They restricted their diet, but it didn't say how or if each group did it the same way. That would have been very interesting to see.

    I didn't see specifics of what was eaten. But, picking out one branch, 25% below TDEE is not a massive deficit, not a VLCD, quite possibly above BMR, quite possibly within limits of 290KJ/KG fat per day, and they still lost FFM. How far should one want to push the loss rate, especially since TDEE adaptation exceeds what is explained by loss of FFM?

    Also, note: CR + EX clearly lost less fat free mass as a fraction of weight loss, and did not experience significant TDEE adaptation.

    That seems kind of important, in a scenario where we'd like to play our best odds, yes? (I see no indication they were in a "tediously controlled" program, from what is said, BTW.)

    For other readers, we should note, also, that "fat free mass" != "muscle", in common usage.

    (Edited to fix typo)
  • kal900
    kal900 Posts: 69 Member
    Options
    Im 5'10", a hefty 113kg or 248lbs. MFP have set my calorie intake at 1220....

    I pretty much manage that eating a reasonable healthy diet. I am gaining @ 5-600 extra calories from exercise, but very rarely eat them back, although I may dip into them as I like the idea of fluctuating calories to keep the body guessing.
    Im no expert, but if that was the level set for me I assume its fairly reasonable to 1 work, and 2 not harm me?

    Ive only just started recording again, but last year it worked well enough in weight loss until my head messed it all up and I went off the rails ;/
  • tomteboda
    tomteboda Posts: 2,171 Member
    Options
    kal900 wrote: »
    Im 5'10", a hefty 113kg or 248lbs. MFP have set my calorie intake at 1220....

    I pretty much manage that eating a reasonable healthy diet. I am gaining @ 5-600 extra calories from exercise, but very rarely eat them back, although I may dip into them as I like the idea of fluctuating calories to keep the body guessing.
    Im no expert, but if that was the level set for me I assume its fairly reasonable to 1 work, and 2 not harm me?

    Ive only just started recording again, but last year it worked well enough in weight loss until my head messed it all up and I went off the rails ;/

    My experience is that eating super-low calorie, like you are, leads to getting heads messed up and going off the rails. At least that's how it worked for me. I did slim-fast for 9 months at age 19 and went from 225 - 165 lbs. I was completely miserable but everyone told me I looked great, so I kept at it. After that , when the weight came back on I was so resistant to experiencing the misery of 1200 calories again that I just ignored the problem for far too long.

    I'm guessing you told MFP you are sedentary and aim to lose 2 lbs / week. That's fine, but if you're marked as sedentary, MFP isn't accounting for you exercising at all (and 500-600 /day means you're working out quite a bit).

    I recommend to eat your exercise calories, you'll find the whole thing much more sustainable. I'm tall like you, and started at 270 lbs. I kept to about 1500 calories the whole first year, got down to 210 that way.. (60 pounds, 12 months = 5 lbs / month). It seems slow to the head, but it's a pretty dramatic change in a year.

    Because I ate my exercise calories and didn't starve myself this time (like I did at 19 when I first lost a bunch of weight) I've been a lot stronger, a lot more emotionally secure, and had way fewer physical problems. For these reasons I believe it'll be possible to keep the weight off where I'd failed at that in the past.

    Technically I've been more successful this way, too, averaging 1850 calories/day ( I walk on average 60 minutes a day, with weekend hikes) I've dropped to 162 lbs.
  • trigden1991
    trigden1991 Posts: 4,658 Member
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    sfa90 wrote: »
    To be honest, I can live of 1200 calories a day for example today I did 1 hour of weight training and 40 min of cardio and I ate today 1263 calories. But, I do feel more tired after a day like this, so I am really trying to eat more food.

    Most people can survive on it. That's not the point.

    The point is that is it not healthy to eat that few calories for prolonged periods unless you are; small, extremely light and inactive.
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    edited January 2017
    Options
    kal900 wrote: »
    Im 5'10", a hefty 113kg or 248lbs. MFP have set my calorie intake at 1220....

    I pretty much manage that eating a reasonable healthy diet. I am gaining @ 5-600 extra calories from exercise, but very rarely eat them back, although I may dip into them as I like the idea of fluctuating calories to keep the body guessing.
    Im no expert, but if that was the level set for me I assume its fairly reasonable to 1 work, and 2 not harm me?

    If you are using this logic it's important to understand that MFP's goal is set with the expectation that you WILL eat exercise calories back (over the course of the week if not that day).

    1200 seems extremely low for someone of your size -- I assume it's because you said sedentary and 1 kg (2.2 lb) per week and MFP calculates that your maintenance is no more than 2300 per day if sedentary. Very few people (certainly women) are going to have a sedentary maintenance of more than 2300 per day, but that doesn't make 1200 a good choice for everyone, including people who are not sedentary at all (and who do active exercise).
  • aneedforchange
    aneedforchange Posts: 75 Member
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    I could definitely do 1200 if I had a desk job or it's a lazy day at home but on my work days ... I really don't think it's possible without me hulking out. I am a massage therapist and if you do 6 hours of massage in a day.. would 1200 be enough for you? Lol I'm personally ravenous and up my calories to between 1750 and 1900 on those days. Still maintaining and losing so i must be burning something!
  • kimny72
    kimny72 Posts: 16,013 Member
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    sfa90 wrote: »
    To be honest, I can live of 1200 calories a day for example today I did 1 hour of weight training and 40 min of cardio and I ate today 1263 calories. But, I do feel more tired after a day like this, so I am really trying to eat more food.

    Most people can survive on it. That's not the point.

    The point is that is it not healthy to eat that few calories for prolonged periods unless you are; small, extremely light and inactive.

    I think this is important to circle back to. This discussion has morphed into "can you survive on 1200 calories". And yeah you can, just like you can survive being bed-ridden, or eating nothing but cat food, or being locked in someone's basement.

    But the OP asked, "Is it unhealthy". And for many people, including the average lightly active woman, eating that little for an extended period of time IS unhealthy. You won't die, you will lose weight, but you are usually doing more harm than it's worth.

    And most non-tiny people who say they eat 1200 calories and exercise every day and feel fabulous, either aren't logging or aren't logging correctly and are eating more than that.