Re: Obesity

Discussion in 'Food and nutrition' started by John Sankey, Jul 2, 2005.

  1. John Sankey

    John Sankey Guest

    I won't contest montygram's point about lipid types and their
    relationships to obesity, but I must note that, when I checked
    with the "Chinese" takeout today, I found two things:

    1: the cook is Thai, a Canadian citizen for 5 years; one of the
    assistants a 3rd generation Canadian Muslim north-Chinese; the
    other assistant a 2nd generation Canadian from Hong Kong! How
    much more Canadian can you get! Including their BMI - at a guess
    a maximum of 20 for the assistants, less than 25 for the cook.
    (Mine's 22.)

    2. They use solely peanut oil - corn oil "tastes awful". They are
    certain that all other Ottawa-area "Chinese" sources also use
    solely peanut oil.

    I assume that montygram can come up with quotes about peanut oil
    equally negative to those we got about corn oil. My point in the
    original post was that all of those fatsos using their cars to
    drive a block were eating something on the order of eight times
    what I, and the take-out staff, normally eat for a main meal.
     
    Tags:


  2. Juhana Harju

    Juhana Harju Guest

    John Sankey wrote:
    :: I won't contest montygram's point about lipid types and their
    :: relationships to obesity, but I must note that, when I checked
    :: with the "Chinese" takeout today, I found two things:
    ::
    :: 1: the cook is Thai, a Canadian citizen for 5 years; one of the
    :: assistants a 3rd generation Canadian Muslim north-Chinese; the
    :: other assistant a 2nd generation Canadian from Hong Kong! How
    :: much more Canadian can you get! Including their BMI - at a guess
    :: a maximum of 20 for the assistants, less than 25 for the cook.
    :: (Mine's 22.)
    ::
    :: 2. They use solely peanut oil - corn oil "tastes awful". They are
    :: certain that all other Ottawa-area "Chinese" sources also use
    :: solely peanut oil.
    ::
    :: I assume that montygram can come up with quotes about peanut oil
    :: equally negative to those we got about corn oil. My point in the
    :: original post was that all of those fatsos using their cars to
    :: drive a block were eating something on the order of eight times
    :: what I, and the take-out staff, normally eat for a main meal.

    I didn't post the Cretan recipe as an example of a healthy recipe. I posted
    it as an example of high use of olive oil in cooking in the Cretan kitchen.

    Some foods might increase the metabolic rate and some might make it slower.
    Still I think that the major reason for obesity is excess caloric intake.
    People simply eat too much and exercise too little. Eating smaller meals and
    preferring foods that have a lower energy density are two strategies that
    have been shown to be associated with greater success in weight control.
    However, I think that the ultimate solution is between the ears.

    --
    Juhana
     
  3. Enrico C

    Enrico C Guest

    On Sat, 2 Jul 2005 20:06:40 +0300, Juhana Harju wrote in
    <news:[email protected]> on sci.med.nutrition :

    [...]

    > Some foods might increase the metabolic rate


    Protein?

    > and some might make it slower.


    Which ones?

    > Still I think that the major reason for obesity is excess caloric intake.
    > People simply eat too much and exercise too little.


    Agreed. As simple as that! :)


    > Eating smaller meals and


    Besides, would you agree on six smaller daily meals rather than two-three
    ordinary ones?


    > preferring foods that have a lower energy density


    and a higher palatability, fulness and satiety indexes, in my view.

    I think palatabily, "food that tastes good", leads to a higher adherence
    rate to a weight control diet, while higher fullness and satiety indexes
    don't let you crave for food after a too short time.

    > are two strategies that
    > have been shown to be associated with greater success in weight control.


    That makes sense to me.
     
  4. montygram

    montygram Guest

    You need to know exactly what is present in the that you literally have
    in front of you. Olive oil, for example, can vary greatly, from being
    "healthy," provided you don't damage it, to being very unhealthy (to
    the point that it's used in rancidity testing because it is so
    suceptible to free radical degradation). Usually, It's about double
    bonds, antioxidant cover, and refining, storing, cooking, though peanut
    oil contains other substances that are problematic (see below).

    I will respond to anyone who posts something like, "Montygram: why
    are the nutritional experts, in general, so lacking in understanding
    about their own area of experise?" However, I don't have the time
    to follow every new post to every old thread. What's going on here
    most of the time is that there are new people who have never read some
    crucial posts, and there are a few people who have been here a while
    and who seem to want to make the same criticisms without being helpful.

    To sum up much of what I've posted briefly:

    Dr. Hans Selye recognized many decades ago that "stress" was the
    key to what we call "chronic diseases," such as heart disease,
    cancer, diabetes, AD, etc., but he only understood in physiologically.

    Denham Harman proposed the "free radical theory of aging" in the
    1970s. This supplies the underlying biochemical mechanism of the
    "stress" that Selye noted.

    In the last decade or so, the evidence has mounted to the point that
    there really is no other hypothesis that makes sense outside of free
    radical activity. Even Dr. Stein of the AHA recently acknowledged this
    in the heart disease context (oxidized, not normal, cholesterol, is the
    problem). The homocysteine revolution, another example, is nothing to
    worry about without the oxidative stress.

    In the 1980s, JoAnn Braganza and others began to realize just how
    dangerous a diet rich in unsaturated fatty acids can be, especially
    considering the typical Western diets, low in antioxidant and usually
    involving high heat cooking. The way the highly unsaturated oils are
    refined is also usually a major problem.

    Recently, biochemist Ray Peat has pointed out that so-called essential
    fatty acids are more dangerous than helpful, except perhaps for
    pregnant women for a short period of time. I've pointed out that my
    grandparents (mid-80s/early 90s) have no source of omega 3 PUFAs and
    never have. They rarely go to restaurants, never consume soybean or
    canola oil, flax seeds, oily fish (hardly any fish, but always white)
    or any other source of omega 3s beyond the tiniest traces, and yet they
    are in pretty good shape, with no "chronic diseases." If omega 3s
    and 6s are essential, they are required in such small amounts that
    nobody should ever go out of their way to consume these potentially
    very dangerous substances.

    My main point is that it is much better to have the Mead acid as the
    PUFA that your body uses to create metabolites used in inflammation and
    other processes (rather than the omega 6 arachidonic acid).

    Those who have criticized me in the past continue to do so, now
    resorting to talking about obvious typographical errors, the cost of
    the use of a dog as an experimental animal, and other such nonsense.
    They are unable to stay on point. It is true that some experiments
    that should be done have not, but that is not my fault. If someone
    wants to fund an experiment that I am capable of administering, such as
    feeds one group of dogs fresh coconut oil while the other group gets
    large amounts of fish oil and safflower oil, I will consider it
    strongly. However, the points I make are scientific, that is, they are
    consistent with known chemical laws as well as the experimental data.
    On the other hand, when a study done on rats (which metabolize fatty
    acids differently) is cited as the reason for the essentiality of omega
    3 and 6 PUFAs, when in fact, it was done in 1930, before all truly
    essential vitamins were known, there is a basic logical problem, let
    alone several scientific ones. Yet in some of the massive nutritional
    textbooks that I own (recent ones), this citation is still made (Burr &
    Burr). The Mead acid is a PUFA, so there is no debate about PUFAs
    specifically. My point is that arachidonic acid, which your body packs
    away when your diet goes beyond trace amounts of omega 6s, is too
    dangerous. I've cited recent studies which make this point
    explicitly in previous posts.


    Remember the greatest experiment you've never heard about, that is,
    hundreds of millions of peoples have lived with a highly saturated
    fatty acid diet, and yet have hardly any "chronic disease," whereas
    in countries like the USA, with very high omega 6 PUFA consumption, we
    are hearing about "epidemics" of various chronic diseases in the
    mainstream media almost constantly these days. Some oils high in omega
    6 PUFAs seem to have the opposite effect, due to the antioxidant
    substances they contain. The best example seems to be sesame oil
    (assuming it's high quality and unrefined). These substances inhibit
    the creation of arachidonic acid in the body (as well as AA
    metabolites). Again, the key is the free radical activity, that is,
    antioxidants can lessen the problem, whereas an unstable molecule like
    AA leads to too much (often resulting in long term, chronic
    inflammatory conditions, such as arthritis, but also cancer, etc.).

    The specifically atherogenic qualities of peanut oil have been
    established (see below), and the lectins are to blame. However, even
    without the lectins, restaurants that use such oils usually reuse them
    (and the oils are usually low quality to begin with). Doing this is
    undeniably dangerous, and I've posted recent evidence that makes this
    point explicitly (see below). Scientists who specialize in this area
    have concluded that these oils, used this way, are incredibly toxic.
    You should be glad that you only get fat, rather than drop dead on the
    spot, because your body has antioxidant mechanisms that deal with it
    for a while. But most people will develop some "chronic disease"
    on such a diet - it's only a matter of how long it will take. Why
    anyone would want to do something so dangerous when there is a tasty,
    healthy alternative (fresh coconut oil, or even just butter isn't
    much of a problem, though I skin the yellowed sides off the sticks
    before using them), is not something that makes any sense.


    Lipids. 1998 Aug;33(8):821-3.
    Lectin may contribute to the atherogenicity of peanut oil.
    Kritchevsky, et al.
    "Peanut oil is unexpectedly atherogenic for rats, rabbits, and
    primates. The lesions it produces are more fibrous than fatty. The
    mechanism underlying the atherogenicity of peanut oil has been elusive.
    Randomization of peanut oil reduces significantly its atherogenic
    properties, but native and randomized peanut oils have similar rates of
    lipolysis, and rats fed the two oils absorb and transport lipids in a
    similar fashion. Peanut oil differs from other oils in having a
    relatively high lectin content, and the randomization process markedly
    reduces the lectin content as well. The biologically active lectin of
    peanut oil has an affinity for glycoproteins found specifically on
    arterial smooth muscle cells. Peanut lectin has been shown to stimulate
    growth of smooth muscle and pulmonary arterial cells..."

    These two are from www.sciencedaily.com:

    5/2/2005
    Food Fried In Vegetable Oil May Contain Toxic Compound

    MINNEAPOLIS / ST. PAUL -- University of Minnesota researchers A. Saari
    Csallany, a professor of food chemistry and nutritional biochemistry,
    and graduate student Christine Seppanen have shown that when highly
    unsaturated vegetable oils are heated at frying temperature (365 F) for
    extended periods--or even for half an hour--a highly toxic compound,
    HNE (4-hydroxy-trans-2-nonenal) forms in the oil.

    Previously, vegetable oils such as soybean, sunflower and corn were
    regarded as heart-healthy because of their high levels of linoleic
    acid, a polyunsaturated fatty acid. HNE is incorporated into fried food
    in the same concentration as it forms in the heated oil. Also, Csallany
    and her colleagues have found three toxic HNE-related compounds (known
    as HHE, HOE and HDE) in heated soybean oil. They will present their
    work at a poster session from 9 a.m. to 2 p.m. Wednesday, May 4, at the
    96th annual meeting of the American Oil Chemists Society in the Salt
    Lake City Convention Center.

    "HNE is a well known, highly toxic compound that is easily absorbed
    from the diet," said Csallany. "The toxicity arises because the
    compound is highly reactive with proteins, nucleic acids--DNA and
    RNA--and other biomolecules. HNE is formed from the oxidation of
    linoleic acid, and reports have related it to several diseases,
    including atherosclerosis, stroke, Parkinson's, Alzheimer's,
    Huntington's and liver diseases."

    Csallany's work underscores the risk of repeated heating, or reusing,
    highly unsaturated oils for frying because HNE accumulates with each
    heating cycle. In future studies, Csallany and her colleagues plan to
    determine how long polyunsaturated oil must be heated at lower
    temperatures in order to form HNE and its related compounds. The study
    was funded by the University of Minnesota.




    6/17/2005
    Toxic Substances In The Oxidation Of Fats And Oils

    Consumers' food health and safety may be affected by the presence of
    micro-organisms and toxic substances in foodstuffs. The cause of the
    presence of toxic substances in food is sometimes due to the fact that
    these have been subject to processes of degradation. The oxidation or
    thermal degradation of food lipids causes deterioration in foodstuffs
    and the generation of toxic substances.

    At the EHU-UPV (University of the Basque Country) Pharmacy Faculty they
    have been studying the process of the oxidative degradation of
    foodstuffs. Research was began with oils, given that these are
    exclusively (99 %) made up of lipids while, in subsequent stages, the
    study was extended to other foods prone to undergoing processes of
    oxidative degradation.

    Processes of oxidative degradation

    Researchers investigated processes of oxidative degradation - notably
    that caused at 70ºC with ventilation - of a broad group of oils with
    very wide-ranging compositions. Another degradation process studied was
    that which is caused by microwave action that does not heat greater
    than a temperature of 190 ºC.

    In both processes deterioration of the oils takes place. In the first
    type of process (70 ºC with ventilation) hydroperoxides are first
    produced and subsequently aldehydes. In the second kind of process
    (microwave) it is basically aldehydes produced. It has to be pointed
    out that both the oxidative conditions and the composition of the oil
    determined the velocity of the degradation and both the nature and
    concentration of the compounds produced.

    These studies have shown, for the first time, that degradation of
    lipids in foods can produce toxic oxygenated aldehydes. These
    compounds, well-known in medical studies for their geno- and cytotoxic
    activity, considered as markers of oxidative stress in cells as well as
    being causal agents of degenerative illnesses, had not previously been
    detected in foodstuffs.

    Researchers have shown that some oils produce these toxic substances in
    greater quantities and at a greater rate. Virgin olive oil was, amongst
    all the oils studied, that which took longer to produce this type of
    compounds and produced a lower concentration of them.

    The technique

    Researchers carried out this investigation, studying the liquid phase
    of the oil by means of Proton Nuclear Magnetic Resonance and Fourier
    Transform Infrarred Spectroscopy, and the gaseous phase of the oil with
    Solid Phase Microextraccion techniques followed by Gas
    Chromatography-Mass Spectrometry. The confirmation of the identity of
    the aldehydes detected was carried out with pattern substances and with
    proton nuclear magnetic resonance spectra for a number of toxic
    aldehydes provided by American researchers who are studying the
    presence of these compounds in damaged cells and tissues.

    The presence of toxic oxygenated aldehydes in fats and oils subjected
    to thermal treatment highlights the need to control the manufacture and
    preparation processes of foodstuffs as well as the fatty material
    employed, given their capacity to generate these oxygenated aldehydes
    responsible for degenerative illnesses. This research opens new lines
    of investigation and perspectives in the field of food safety.
     
  5. Enrico C

    Enrico C Guest

    On 2 Jul 2005 17:06:19 -0700, montygram wrote in
    <news:[email protected]> on
    sci.med.nutrition :

    > You need to know exactly what is present in the that you literally have
    > in front of you. Olive oil, for example, can vary greatly, from being
    > "healthy," provided you don't damage it, to being very unhealthy (to
    > the point that it's used in rancidity testing because it is so
    > suceptible to free radical degradation). Usually, It's about double
    > bonds, antioxidant cover, and refining,


    Use "extra virgin olive oil", that is to say the unrefined oil.

    > storing,


    I gather olive oil, a mostly monounsaturated oil, is more stable than
    mostly polyunsaturated oils, anyway.


    > cooking,


    Cooking destroys the scent of olive oil, in my view. I only use it
    uncooked.
    Besides, I gather uncooked oils are healthier than the same oils when
    cooked.

    > though peanut
    > oil contains other substances that are problematic (see below).
    >
    > I will respond to anyone who posts something like, "Montygram: why
    > are the nutritional experts, in general, so lacking in understanding
    > about their own area of experise?" However, I don't have the time
    > to follow every new post to every old thread. What's going on here
    > most of the time is that there are new people who have never read some
    > crucial posts, and there are a few people who have been here a while
    > and who seem to want to make the same criticisms without being helpful.
    >
    > To sum up much of what I've posted briefly:
    >
    > Dr. Hans Selye recognized many decades ago that "stress" was the
    > key to what we call "chronic diseases," such as heart disease,
    > cancer, diabetes, AD, etc., but he only understood in physiologically.
    >
    > Denham Harman proposed the "free radical theory of aging" in the
    > 1970s. This supplies the underlying biochemical mechanism of the
    > "stress" that Selye noted.
    >
    > In the last decade or so, the evidence has mounted to the point that
    > there really is no other hypothesis that makes sense outside of free
    > radical activity. Even Dr. Stein of the AHA recently acknowledged this
    > in the heart disease context (oxidized, not normal, cholesterol, is the
    > problem). The homocysteine revolution, another example, is nothing to
    > worry about without the oxidative stress.
    >
    > In the 1980s, JoAnn Braganza and others began to realize just how
    > dangerous a diet rich in unsaturated fatty acids can be, especially
    > considering the typical Western diets, low in antioxidant and usually
    > involving high heat cooking.


    I am not typical... :)

    > The way the highly unsaturated oils are
    > refined is also usually a major problem.


    You can find unrefined, cold-pressed oils, though...

    > Recently, biochemist Ray Peat has pointed out that so-called essential
    > fatty acids are more dangerous than helpful, except perhaps for
    > pregnant women for a short period of time. I've pointed out that my
    > grandparents (mid-80s/early 90s) have no source of omega 3 PUFAs and
    > never have. They rarely go to restaurants, never consume soybean or
    > canola oil, flax seeds, oily fish (hardly any fish, but always white)
    > or any other source of omega 3s beyond the tiniest traces, and yet they
    > are in pretty good shape, with no "chronic diseases." If omega 3s
    > and 6s are essential, they are required in such small amounts that
    > nobody should ever go out of their way to consume these potentially
    > very dangerous substances.


    It seems to me that omega 3s are found, in small quantities, in several
    foods other than fish or oils. EPA and DHA, for instance, are also found in
    meat.

    >
    > My main point is that it is much better to have the Mead acid as the
    > PUFA that your body uses to create metabolites used in inflammation and
    > other processes (rather than the omega 6 arachidonic acid).
    >
    > Those who have criticized me in the past continue to do so, now
    > resorting to talking about obvious typographical errors, the cost of
    > the use of a dog as an experimental animal, and other such nonsense.
    > They are unable to stay on point. It is true that some experiments
    > that should be done have not, but that is not my fault. If someone
    > wants to fund an experiment that I am capable of administering, such as
    > feeds one group of dogs fresh coconut oil while the other group gets
    > large amounts of fish oil and safflower oil, I will consider it
    > strongly. However, the points I make are scientific, that is, they are
    > consistent with known chemical laws as well as the experimental data.
    > On the other hand, when a study done on rats (which metabolize fatty
    > acids differently) is cited as the reason for the essentiality of omega
    > 3 and 6 PUFAs, when in fact, it was done in 1930, before all truly
    > essential vitamins were known, there is a basic logical problem, let
    > alone several scientific ones. Yet in some of the massive nutritional
    > textbooks that I own (recent ones), this citation is still made (Burr &
    > Burr). The Mead acid is a PUFA, so there is no debate about PUFAs
    > specifically. My point is that arachidonic acid, which your body packs
    > away when your diet goes beyond trace amounts of omega 6s, is too
    > dangerous. I've cited recent studies which make this point
    > explicitly in previous posts.
    >
    >
    > Remember the greatest experiment you've never heard about, that is,
    > hundreds of millions of peoples have lived with a highly saturated
    > fatty acid diet, and yet have hardly any "chronic disease," whereas
    > in countries like the USA, with very high omega 6 PUFA consumption, we
    > are hearing about "epidemics" of various chronic diseases in the
    > mainstream media almost constantly these days. Some oils high in omega
    > 6 PUFAs seem to have the opposite effect, due to the antioxidant
    > substances they contain. The best example seems to be sesame oil
    > (assuming it's high quality and unrefined). These substances inhibit
    > the creation of arachidonic acid in the body (as well as AA
    > metabolites). Again, the key is the free radical activity, that is,
    > antioxidants can lessen the problem, whereas an unstable molecule like
    > AA leads to too much (often resulting in long term, chronic
    > inflammatory conditions, such as arthritis, but also cancer, etc.).
    >
    > The specifically atherogenic qualities of peanut oil have been
    > established (see below), and the lectins are to blame. However, even
    > without the lectins, restaurants that use such oils usually reuse them
    > (and the oils are usually low quality to begin with). Doing this is
    > undeniably dangerous, and I've posted recent evidence that makes this
    > point explicitly (see below). Scientists who specialize in this area
    > have concluded that these oils, used this way, are incredibly toxic.
    > You should be glad that you only get fat, rather than drop dead on the
    > spot, because your body has antioxidant mechanisms that deal with it
    > for a while. But most people will develop some "chronic disease"
    > on such a diet - it's only a matter of how long it will take. Why
    > anyone would want to do something so dangerous when there is a tasty,
    > healthy alternative (fresh coconut oil, or even just butter isn't
    > much of a problem, though I skin the yellowed sides off the sticks
    > before using them), is not something that makes any sense.



    > Lipids. 1998 Aug;33(8):821-3.
    > Lectin may contribute to the atherogenicity of peanut oil.
    > Kritchevsky, et al.
    > "Peanut oil is unexpectedly atherogenic for rats, rabbits, and
    > primates. The lesions it produces are more fibrous than fatty. The
    > mechanism underlying the atherogenicity of peanut oil has been elusive.
    > Randomization of peanut oil reduces significantly its atherogenic
    > properties, but native and randomized peanut oils have similar rates of
    > lipolysis, and rats fed the two oils absorb and transport lipids in a
    > similar fashion. Peanut oil differs from other oils in having a
    > relatively high lectin content, and the randomization process markedly
    > reduces the lectin content as well. The biologically active lectin of
    > peanut oil has an affinity for glycoproteins found specifically on
    > arterial smooth muscle cells. Peanut lectin has been shown to stimulate
    > growth of smooth muscle and pulmonary arterial cells..."
    >
    > These two are from www.sciencedaily.com:
    >
    > 5/2/2005
    > Food Fried In Vegetable Oil May Contain Toxic Compound
    >
    > MINNEAPOLIS / ST. PAUL -- University of Minnesota researchers A. Saari
    > Csallany, a professor of food chemistry and nutritional biochemistry,
    > and graduate student Christine Seppanen have shown that when highly
    > unsaturated vegetable oils are heated at frying temperature (365 F) for
    > extended periods--or even for half an hour--a highly toxic compound,
    > HNE (4-hydroxy-trans-2-nonenal) forms in the oil.
    >
    > Previously, vegetable oils such as soybean, sunflower and corn were
    > regarded as heart-healthy because of their high levels of linoleic
    > acid, a polyunsaturated fatty acid. HNE is incorporated into fried food
    > in the same concentration as it forms in the heated oil. Also, Csallany
    > and her colleagues have found three toxic HNE-related compounds (known
    > as HHE, HOE and HDE) in heated soybean oil. They will present their
    > work at a poster session from 9 a.m. to 2 p.m. Wednesday, May 4, at the
    > 96th annual meeting of the American Oil Chemists Society in the Salt
    > Lake City Convention Center.
    >
    > "HNE is a well known, highly toxic compound that is easily absorbed
    > from the diet," said Csallany. "The toxicity arises because the
    > compound is highly reactive with proteins, nucleic acids--DNA and
    > RNA--and other biomolecules. HNE is formed from the oxidation of
    > linoleic acid, and reports have related it to several diseases,
    > including atherosclerosis, stroke, Parkinson's, Alzheimer's,
    > Huntington's and liver diseases."
    >
    > Csallany's work underscores the risk of repeated heating, or reusing,
    > highly unsaturated oils for frying because HNE accumulates with each
    > heating cycle. In future studies, Csallany and her colleagues plan to
    > determine how long polyunsaturated oil must be heated at lower
    > temperatures in order to form HNE and its related compounds. The study
    > was funded by the University of Minnesota.
    >
    >
    >
    >
    > 6/17/2005
    > Toxic Substances In The Oxidation Of Fats And Oils
    >
    > Consumers' food health and safety may be affected by the presence of
    > micro-organisms and toxic substances in foodstuffs. The cause of the
    > presence of toxic substances in food is sometimes due to the fact that
    > these have been subject to processes of degradation. The oxidation or
    > thermal degradation of food lipids causes deterioration in foodstuffs
    > and the generation of toxic substances.
    >
    > At the EHU-UPV (University of the Basque Country) Pharmacy Faculty they
    > have been studying the process of the oxidative degradation of
    > foodstuffs. Research was began with oils, given that these are
    > exclusively (99 %) made up of lipids while, in subsequent stages, the
    > study was extended to other foods prone to undergoing processes of
    > oxidative degradation.
    >
    > Processes of oxidative degradation
    >
    > Researchers investigated processes of oxidative degradation - notably
    > that caused at 70ºC with ventilation - of a broad group of oils with
    > very wide-ranging compositions. Another degradation process studied was
    > that which is caused by microwave action that does not heat greater
    > than a temperature of 190 ºC.
    >
    > In both processes deterioration of the oils takes place. In the first
    > type of process (70 ºC with ventilation) hydroperoxides are first
    > produced and subsequently aldehydes. In the second kind of process
    > (microwave) it is basically aldehydes produced. It has to be pointed
    > out that both the oxidative conditions and the composition of the oil
    > determined the velocity of the degradation and both the nature and
    > concentration of the compounds produced.
    >
    > These studies have shown, for the first time, that degradation of
    > lipids in foods can produce toxic oxygenated aldehydes. These
    > compounds, well-known in medical studies for their geno- and cytotoxic
    > activity, considered as markers of oxidative stress in cells as well as
    > being causal agents of degenerative illnesses, had not previously been
    > detected in foodstuffs.
    >
    > Researchers have shown that some oils produce these toxic substances in
    > greater quantities and at a greater rate. Virgin olive oil was, amongst
    > all the oils studied, that which took longer to produce this type of
    > compounds and produced a lower concentration of them.
    >
    > The technique
    >
    > Researchers carried out this investigation, studying the liquid phase
    > of the oil by means of Proton Nuclear Magnetic Resonance and Fourier
    > Transform Infrarred Spectroscopy, and the gaseous phase of the oil with
    > Solid Phase Microextraccion techniques followed by Gas
    > Chromatography-Mass Spectrometry. The confirmation of the identity of
    > the aldehydes detected was carried out with pattern substances and with
    > proton nuclear magnetic resonance spectra for a number of toxic
    > aldehydes provided by American researchers who are studying the
    > presence of these compounds in damaged cells and tissues.
    >
    > The presence of toxic oxygenated aldehydes in fats and oils subjected
    > to thermal treatment highlights the need to control the manufacture and
    > preparation processes of foodstuffs as well as the fatty material
    > employed, given their capacity to generate these oxygenated aldehydes
    > responsible for degenerative illnesses. This research opens new lines
    > of investigation and perspectives in the field of food safety.
     
  6. Enrico C

    Enrico C Guest

    On Sun, 3 Jul 2005 02:52:46 +0200, Enrico C wrote in
    <news:[email protected]> on sci.med.nutrition :
    [...]
    > Cooking destroys the scent of olive oil, in my view. I only use it
    > uncooked.


    Well... usually...
    I must confess today I used some oil to brown garlic and herbs for a fish
    soup :)

    --
    Enrico C
     
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