contradictory information about nutrition

Discussion in 'Food and nutrition' started by Bennett Haselto, Apr 11, 2004.

  1. I'm trying to learn a lot about nutrition from the ground up. I don't
    know if this will help with weight loss/maintenance and general
    health; one school of thought is that if we knew more, we'd be
    healthier, but of course another school of thought is that we know
    what things are bad for us but we eat them anyway, and what we need is
    more willpower, not more knowledge :)

    Anyway, it seems like if you go searching for information
    beyond the basics of what types of fats there are and what a
    calorie measures, there is (to make a point which must be
    crashingly obvious to anyone who has studied up on
    nutrition) a lot of contradictory information and advice.
    Sometimes this comes from different advice sources giving
    priority to different goals (one page may explain
    convincinly why the Atkins diet tricks your body into
    burning up its fat stores; another page might acknowledge
    that this is true, but that saturated fats in meat can also
    cause an increase in cholesterol levels, which won't be
    reflected in weight gain but can have other harmful
    effects). And sometimes two sources of information just say
    the exact opposite about what happens in a given situation.

    This page: http://www.countcarbs.com/advice/LCG_Myth_Realit-
    y_Ketosis.htm says 'If your protein intake is adequate, the
    body will not cannibalize its own protein - muscle - but
    will utilize the protein eaten for what is called, in
    metabolic terms, "gluconeogenesis".'
    i.e. when your carbs are severely limited, your body uses
    dietary protein for glucose *first*, and then *only* if
    dietary protein is insufficient, does your body begin
    burning its own muscles for glucose.

    On the other hand, this page:
    http://www.dietitian.com/locarb.html says "The problem is
    when you've depleted your stores of glycogen (stored glucose
    in muscle and lean tissue) your body turns to burning
    muscles or organs (lean muscle tissue) and dietary protein
    or fat to provide blood glucose to supply energy needs. When
    this happens, your basal metabolic rate drops because you
    have less lean muscle tissue burning calories and your body
    thinks its starving and cuts back on energy requirements."
    In other words, if you don't eat enough carbs to make
    glucose, your body starts making glucose from dietary
    protein and the body's own muscles *at the same time*.

    Unless I read it wrong, it sounds like these can't both be
    correct at the same time -- and there are lots of other
    examples. Is the contradictory information due to lack of
    scientific knowledge about what actually happens, or is it
    just because columnists are not reliable?

    And sometimes, even if it's clear what an article says, the
    underlying logic just begs more questions. For example, the
    http://www.countcarbs.com/advice/LCG_Myth_Reality_Ketosis.h-
    tm article says that your body gets energy either from from
    glucose or from fat stores, and the idea behind limiting
    carbs is to limit the amount of glucose that gets made, so
    that your body starts burning fat for energy. But it goes on
    to say that since you need glucose for brain function, you
    should make sure you eat enough protein to get that glucose.
    This begs the question: if you need X amount of glucose per
    day (but no more -- so that your body will turn to fat
    stores for energy), then what difference does it make
    whether you get that from carbohydrates or from protein?

    By analogy, if I didn't know anything about computer viruses
    and Internet security threats, and you tried to learn how to
    protect yourself by reading the information that columnists
    have put out there, it would be a huge mess sorting out all
    the conflicting advice. Now that I have about an expert-
    level understanding of those topics, when I read some
    columnists' advice about the subject, I can usually tell how
    they might have reached those conclusions, and how with a
    sentence change or two the article would be pretty accurate
    -- but I can't imagine actually trying to learn from reading
    all that contradictory advice. It took learning about how
    computers and email worked, from the ground up, before I
    could tell which advice out there was valid. Is it the same
    for nutrition experts in this group, reading all the columns
    out there about diet and nutrition? Would it be better just
    to learn about nutrition from the ground up, to get to the
    point where you could be proofreading other people's
    columns, than to try and learn from the columns themselves?

    Oh, and if anyone happens to know the answer to the above
    question (when your body runs out of glucose from
    carbohydrates, does it make more glucose from dietary
    protein first and only burn up your muscles when the dietary
    protein runs out, or does it burn up both at the same time),
    that would also be useful...

    -Bennett
     
    Tags:


  2. °¿ °

    °¿ ° Guest

    Bennett Haselton wrote

    <snip>

    > -Bennet

    Why don't you ask the guys who actually know these answers
    from experience not just theory. I wresled with these same
    dilemmas, and came to the conclusion that bodybuilders can
    be living proof of concept of ideas if you get into the
    right crowd (read natural not drug assisted). Search for
    articles by Lyle Mcdonald in
    http://groups.google.com.au/advanced_group_search?hl=en and
    have a look at http://www.bodyrecomposition.com/ and
    http://www.thinkmuscle.com/articles/mcdonald/index.htm. Some
    of the info is a little out of date but i doubt if thousands
    of weight trainers/bodybuilders would be hanging on this
    guys every word if he didn't have something right.
    --
    °¿ °
    2.6.4 GNU/Linux AMD Athlon(tm) Processor
    2:7:20 up 9 days, 10:17, 1 user, load average: 0.00,
    0.00, 0.00
     
  3. Mirek Fidler

    Mirek Fidler Guest

    "Bennett Haselton" <[email protected]> píse v diskusním príspevku
    news:[email protected]...
    > I'm trying to learn a lot about nutrition from the ground
    > up. I don't

    So do I, just perhaps for several months longer :)

    > Anyway, it seems like if you go searching for information
    > beyond the basics of what types of fats there are and what
    > a calorie measures, there is (to make a point which must
    > be crashingly obvious to anyone who has studied up on
    > nutrition) a lot of contradictory information and advice.

    Welcome to the world in nutrition "science" :)

    > priority to different goals (one page may explain
    > convincinly why the Atkins diet tricks your body into
    > burning up its fat stores; another page might acknowledge
    > that this is true, but that saturated fats in

    BTW, I would finally like if somebody would show me a
    biochemic pathway that causes this satfat problem....

    That said, there probably are problems associated with
    saturated fats, or better to say, with SOME saturated fats,
    but if they change cholesterol levels, then it could be only
    indirectly.

    > the same time -- and there are lots of other examples. Is
    > the contradictory information due to lack of scientific
    > knowledge about what actually happens, or is it just
    > because columnists are not reliable?

    I think both.

    > for energy. But it goes on to say that since you need
    > glucose for brain function, you should make sure you eat
    > enough protein to get

    Actually, if you eat low-carb for some time, brain
    requirements change, it starts to burn ketones instead
    of glucose.

    Normally you need about 100g of glucose per day for brain,
    but after adaptation your requirements will drop to about
    30g / day and rest of energy will be obtained from ketone
    bodies. BTW, most people (including
    me) report improved brain performance when running on
    ketones.

    > that glucose. This begs the question: if you need X amount
    > of glucose per day (but no more -- so that your body will
    > turn to fat stores for energy), then what difference does
    > it make whether you get that from carbohydrates or from
    > protein?

    Carbs inhibit glucogenesis. Of course, switching between glucose-
    >fat and fat->glucose happens all the time, anyway while glucose-
    >fat is started quite fast (it must be, unless BG would go
    too high), fat->glucose gets much longer to kick-in and the
    problem is that body reacts to low BG with hunger.

    > reading all the columns out there about diet and
    > nutrition? Would it be better just to learn about
    > nutrition from the ground up, to get to the point where
    > you could be proofreading other people's columns, than to
    > try and learn from the columns themselves?

    I think you should start with biochemistry first:

    http://www.indstate.edu/thcme/mwking/home.html

    Mirek
     
  4. Mike V

    Mike V Guest

    "Mirek Fidler" <[email protected]> wrote in message
    news:[email protected]...
    >
    > "Bennett Haselton" <[email protected]> píse v
    > diskusním príspevku
    > news:[email protected]...
    > > I'm trying to learn a lot about nutrition from the
    > > ground up. I don't
    >
    SNIP
    >
    > I think you should start with biochemistry first:
    >
    > http://www.indstate.edu/thcme/mwking/home.html
    >
    > Mirek
    >
    >
    ****

    And so should we all! Mirek, a great site, perhaps more than
    a little dangerous for mooshian dogmatists. Hope we do not
    hear of sudden heart attacks. Perhaps it should carry a
    warning label! Mike V
     
  5. Moosh:)

    Moosh:) Guest

    On Tue, 13 Apr 2004 10:58:06 +0200, "Mirek Fidler" <[email protected]>
    posted:

    >
    >"Bennett Haselton" <[email protected]> píse v
    >diskusním príspevku
    >news:[email protected]...
    >> I'm trying to learn a lot about nutrition from the ground
    >> up. I don't
    >
    >So do I, just perhaps for several months longer :)
    >
    >> Anyway, it seems like if you go searching for information
    >> beyond the basics of what types of fats there are and
    >> what a calorie measures, there is (to make a point which
    >> must be crashingly obvious to anyone who has studied up
    >> on nutrition) a lot of contradictory information and
    >> advice.
    >
    >Welcome to the world in nutrition "science" :)
    >
    >> priority to different goals (one page may explain
    >> convincinly why the Atkins diet tricks your body into
    >> burning up its fat stores; another page might acknowledge
    >> that this is true, but that saturated fats in
    >
    >BTW, I would finally like if somebody would show me a
    >biochemic pathway that causes this satfat problem....
    >
    >That said, there probably are problems associated with
    >saturated fats, or better to say, with SOME saturated fats,
    >but if they change cholesterol levels, then it could be
    >only indirectly.

    Surely sat fats are not a particular problem when you are
    not fat and do enough exercise. Afterall, isn't your
    body's fat stores sat fat? Seems to me that lots of
    foodstuffs are a problem when too many calories are eaten
    and the body accumulates too much fat storage and less and
    less exercise is taken.

    A varied wholefood diet with no excess of calories and with
    regular moderate exercise brings no problems with metabolism
    abnormalities.

    >> the same time -- and there are lots of other examples. Is
    >> the contradictory information due to lack of scientific
    >> knowledge about what actually happens, or is it just
    >> because columnists are not reliable?
    >
    >I think both.

    I don't believe there is a particular lack of scientific
    knowledge. Columnists are renowned.....

    >> for energy. But it goes on to say that since you need
    >> glucose for brain function, you should make sure you eat
    >> enough protein to get
    >
    >Actually, if you eat low-carb for some time, brain
    >requirements change, it starts to burn ketones instead
    >of glucose.

    Can you point me to some description of this, Mirek?
    The brain always objects to burning mostly ketone
    bodies I understand. Gluconeogenis increases until it
    has enough glucose.

    >Normally you need about 100g of glucose per day for brain,
    >but after adaptation your requirements will drop to about
    >30g / day and rest of energy will be obtained from ketone
    >bodies. BTW, most people (including
    >me) report improved brain performance when running on
    > ketones.

    That's assuming that it really IS running on ketones. I've
    only heard this from the low carbers.

    >> that glucose. This begs the question: if you need X
    >> amount of glucose per day (but no more -- so that your
    >> body will turn to fat stores for energy), then what
    >> difference does it make whether you get that from
    >> carbohydrates or from protein?
    >
    >Carbs inhibit glucogenesis. Of course, switching between
    >glucose->fat and fat->glucose happens all the time, anyway
    >while glucose->fat is started quite fast (it must be,
    >unless BG would go too high), fat->glucose gets much longer
    >to kick-in and the problem is that body reacts to low BG
    >with hunger.

    Well 10% of fat and much protein can be converted to
    glucose.

    >> reading all the columns out there about diet and
    >> nutrition? Would it be better just to learn about
    >> nutrition from the ground up, to get to the point where
    >> you could be proofreading other people's columns, than to
    >> try and learn from the columns themselves?
    >
    >I think you should start with biochemistry first:
    >
    >http://www.indstate.edu/thcme/mwking/home.html

    Good site, Thanks.
     
  6. Moosh:)

    Moosh:) Guest

    On 11 Apr 2004 22:48:17 -0700, [email protected] (Bennett
    Haselton) posted:

    >I'm trying to learn a lot about nutrition from the ground
    >up. I don't know if this will help with weight
    >loss/maintenance and general health; one school of thought
    >is that if we knew more, we'd be healthier, but of course
    >another school of thought is that we know what things are
    >bad for us but we eat them anyway, and what we need is more
    >willpower, not more knowledge :)
    >
    >Anyway, it seems like if you go searching for information
    >beyond the basics of what types of fats there are and what
    >a calorie measures, there is (to make a point which must be
    >crashingly obvious to anyone who has studied up on
    >nutrition) a lot of contradictory information and advice.
    >Sometimes this comes from different advice sources giving
    >priority to different goals (one page may explain
    >convincinly why the Atkins diet tricks your body into
    >burning up its fat stores; another page might acknowledge
    >that this is true, but that saturated fats in meat can also
    >cause an increase in cholesterol levels, which won't be
    >reflected in weight gain but can have other harmful
    >effects). And sometimes two sources of information just say
    >the exact opposite about what happens in a given situation.
    >
    >This page: http://www.countcarbs.com/advice/LCG_Myth_Reali-
    >ty_Ketosis.htm says 'If your protein intake is adequate,
    >the body will not cannibalize its own protein - muscle -
    >but will utilize the protein eaten for what is called, in
    >metabolic terms, "gluconeogenesis".'
    >i.e. when your carbs are severely limited, your body uses
    > dietary protein for glucose *first*, and then *only*
    > if dietary protein is insufficient, does your body
    > begin burning its own muscles for glucose.
    >
    >On the other hand, this page:
    >http://www.dietitian.com/locarb.html says "The problem is
    >when you've depleted your stores of glycogen (stored
    >glucose in muscle and lean tissue) your body turns to
    >burning muscles or organs (lean muscle tissue) and dietary
    >protein or fat to provide blood glucose to supply energy
    >needs. When this happens, your basal metabolic rate drops
    >because you have less lean muscle tissue burning calories
    >and your body thinks its starving and cuts back on energy
    >requirements." In other words, if you don't eat enough
    >carbs to make glucose, your body starts making glucose
    >from dietary protein and the body's own muscles *at the
    >same time*.
    >
    >Unless I read it wrong, it sounds like these can't both be
    >correct at the same time -- and there are lots of other
    >examples. Is the contradictory information due to lack of
    >scientific knowledge about what actually happens, or is it
    >just because columnists are not reliable?

    Columnists are often quite wrong. The apparent
    contradictions are probably because energy from fat was not
    taken into account, and also whether excess energy was being
    consumed, or just the right amount or less than is needed.

    >And sometimes, even if it's clear what an article says, the
    >underlying logic just begs more questions. For example, the
    >http://www.countcarbs.com/advice/LCG_Myth_Reality_Ketosis.-
    >htm article says that your body gets energy either from
    >from glucose or from fat stores, and the idea behind
    >limiting carbs is to limit the amount of glucose that gets
    >made, so that your body starts burning fat for energy. But
    >it goes on to say that since you need glucose for brain
    >function, you should make sure you eat enough protein to
    >get that glucose. This begs the question: if you need X
    >amount of glucose per day (but no more -- so that your body
    >will turn to fat stores for energy), then what difference
    >does it make whether you get that from carbohydrates or
    >from protein?

    It doesn't, so long as you are not eating way too much
    energy. Then all sorts of problems rear their ugly heads.

    >By analogy, if I didn't know anything about computer
    >viruses and Internet security threats, and you tried to
    >learn how to protect yourself by reading the information
    >that columnists have put out there, it would be a huge mess
    >sorting out all the conflicting advice. Now that I have
    >about an expert-level understanding of those topics, when I
    >read some columnists' advice about the subject, I can
    >usually tell how they might have reached those conclusions,
    >and how with a sentence change or two the article would be
    >pretty accurate -- but I can't imagine actually trying to
    >learn from reading all that contradictory advice. It took
    >learning about how computers and email worked, from the
    >ground up, before I could tell which advice out there was
    >valid. Is it the same for nutrition experts in this group,
    >reading all the columns out there about diet and nutrition?
    >Would it be better just to learn about nutrition from the
    >ground up, to get to the point where you could be
    >proofreading other people's columns, than to try and learn
    >from the columns themselves?
    >
    >Oh, and if anyone happens to know the answer to the above
    >question (when your body runs out of glucose from
    >carbohydrates, does it make more glucose from dietary
    >protein first and only burn up your muscles when the
    >dietary protein runs out, or does it burn up both at the
    >same time), that would also be useful...

    >
    >-Bennett
     
  7. Dec

    Dec Guest

    "Moosh:)" <[email protected]> wrote in message news:[email protected]...
    > On 11 Apr 2004 22:48:17 -0700, [email protected]
    > (Bennett Haselton) posted:
    >
    > >I'm trying to learn a lot about nutrition from the ground
    > >up. I don't know if this will help with weight
    > >loss/maintenance and general health; one school of
    > >thought is that if we knew more, we'd be healthier, but
    > >of course another school of thought is that we know what
    > >things are bad for us but we eat them anyway, and what we
    > >need is more willpower, not more knowledge :)
    > >
    > >Anyway, it seems like if you go searching for information
    > >beyond the basics of what types of fats there are and
    > >what a calorie measures, there is (to make a point which
    > >must be crashingly obvious to anyone who has studied up
    > >on nutrition) a lot of contradictory information and
    > >advice. Sometimes this comes from different advice
    > >sources giving priority to different goals (one page may
    > >explain convincinly why the Atkins diet tricks your body
    > >into burning up its fat stores; another page might
    > >acknowledge that this is true, but that saturated fats in
    > >meat can also cause an increase in cholesterol levels,
    > >which won't be reflected in weight gain but can have
    > >other harmful effects). And sometimes two sources of
    > >information just say the exact opposite about what
    > >happens in a given situation.
    > >
    > >This page: http://www.countcarbs.com/advice/LCG_Myth_Rea-
    > >lity_Ketosis.htm says 'If your protein intake is
    > >adequate, the body will not cannibalize its own protein -
    > >muscle - but will utilize the protein eaten for what is
    > >called, in metabolic terms, "gluconeogenesis".'
    > >i.e. when your carbs are severely limited, your body uses
    > > dietary protein for glucose *first*, and then *only*
    > > if dietary protein is insufficient, does your body
    > > begin burning its own muscles for glucose.
    > >
    > >On the other hand, this page:
    > >http://www.dietitian.com/locarb.html says "The problem is
    > >when you've depleted your stores of glycogen (stored
    > >glucose in muscle and lean tissue) your body turns to
    > >burning muscles or organs (lean muscle tissue) and
    > >dietary protein or fat to provide blood glucose to supply
    > >energy needs. When this happens, your basal metabolic
    > >rate drops because you have less lean muscle tissue
    > >burning calories and your body thinks its starving and
    > >cuts back on energy requirements." In other words, if you
    > >don't eat enough carbs to make glucose, your body starts
    > >making glucose from dietary protein and the body's own
    > >muscles *at the same time*.
    > >
    > >Unless I read it wrong, it sounds like these can't both
    > >be correct at the same time -- and there are lots of
    > >other examples. Is the contradictory information due to
    > >lack of scientific knowledge about what actually happens,
    > >or is it just because columnists are not reliable?
    >
    > Columnists are often quite wrong. The apparent
    > contradictions are probably because energy from fat was
    > not taken into account, and also whether excess energy
    > was being consumed, or just the right amount or less than
    > is needed.
    >
    > >And sometimes, even if it's clear what an article says,
    > >the underlying logic just begs more questions. For
    > >example, the http://www.countcarbs.com/advice/LCG_Myth_R-
    > >eality_Ketosis.htm article says that your body gets
    > >energy either from from glucose or from fat stores, and
    > >the idea behind limiting carbs is to limit the amount of
    > >glucose that gets made, so that your body starts burning
    > >fat for energy. But it goes on to say that since you need
    > >glucose for brain function, you should make sure you eat
    > >enough protein to get that glucose. This begs the
    > >question: if you need X amount of glucose per day (but no
    > >more -- so that your body will turn to fat stores for
    > >energy), then what difference does it make whether you
    > >get that from carbohydrates or from protein?
    >
    > It doesn't, so long as you are not eating way too much
    > energy. Then all sorts of problems rear their ugly heads.
    >
    > >By analogy, if I didn't know anything about computer
    > >viruses and Internet security threats, and you tried to
    > >learn how to protect yourself by reading the information
    > >that columnists have put out there, it would be a huge
    > >mess sorting out all the conflicting advice. Now that I
    > >have about an expert-level understanding of those topics,
    > >when I read some columnists' advice about the subject, I
    > >can usually tell how they might have reached those
    > >conclusions, and how with a sentence change or two the
    > >article would be pretty accurate -- but I can't imagine
    > >actually trying to learn from reading all that
    > >contradictory advice. It took learning about how
    > >computers and email worked, from the ground up, before I
    > >could tell which advice out there was valid. Is it the
    > >same for nutrition experts in this group, reading all the
    > >columns out there about diet and nutrition? Would it be
    > >better just to learn about nutrition from the ground up,
    > >to get to the point where you could be proofreading other
    > >people's columns, than to try and learn from the columns
    > >themselves?
    > >
    > >Oh, and if anyone happens to know the answer to the above
    > >question (when your body runs out of glucose from
    > >carbohydrates, does it make more glucose from dietary
    > >protein first and only burn up your muscles when the
    > >dietary protein runs out, or does it burn up both at the
    > >same time), that would also be useful...
    >
    >
    >
    >
    > >
    > >-Bennett
     
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