From: sbharris@ix.netcom.com(Steven B. Harris)
Subject: Re: any comments on flax seed oil????
Date: Wed, 15 Oct 1997
Newsgroups: sci.life-extension,alt.folklore.herbs,sci.med.nutrition,
	misc.health.alternative

In <34440131.57CB@NOSPAM.cs.ualberta.ca> Necromancer
<joanna@NOSPAM.cs.ualberta.ca> writes:

>Dr. Van Beveren wrote:
>
>> These are the "hard" fats that have no elasticity - margarine for
>> instance, is only one chemical step from being plastic and cannot
>> function as a hormone precursor. Shortenings, too are very "sticky"
>> bakery products, french fries, bagged chips, candies and other deep
>> fried "foods". The average human in the U.S. consumes more than 12
>> pounds of these "trans-fatty" acids loaded with free radical,
>> rancidified fats. There is much more to this subject but this should do
>> for now. (Read "Fats and Oils" by Udo Erasmus)
>
>To this I will add:
>
>It has to do with the hydrogen molecules attached to fat molecules.
>Saturated fats have as many hydrogen molecules attached as they possibly
>can (they are usually solid, animal fats) while unsaturated fats (mostly
>vegetable oils) are missing some of those hydrogen molecules. Fats like
>margarine are hydrogenated fats. In order to make them more solid, they
>have hydrogen molecules attached -- which, of course makes them more like
>saturated fats and some of their beneficial properties are lost.



    Yes.  Also in the process, some natural unsaturated fats are turned
into trans-unsaturated fats, in a process where the hydrogen is added
to the molecule, then lost again, leaving the molecule twisted into a
different shape about the normally rigid pi double bond.   The body
feeds these trans-fats more directly into the cholesterol synthesis
pathway.  Trans-fats are a step in the oxidation of saturated fats, and
also the transformation of saturated fats into cholesterol.  Some of
the regulation of the process happens before this step, and thus
trans-fats from hydrogenated oils "short-circuit" this process, and
raise cholesterol levels.  You'll read stuff about how trans-fats are
"unnatural."  They aren't.  They are made by bacteria and found
(therefore) in milk.  And they are normally produced by your cells.
They are perfectly natural.  And also bad for you <g>.  Stay away from
hydrogenated oils (except in small quantities).

                                      Steve Harris, M.D.

From: sbharris@ix.netcom.com(Steven B. Harris)
Newsgroups: sci.med.nutrition
Subject: Re: hydrogentated oil
Date: 17 Jan 1998 02:47:14 GMT

In <19980117010500.UAA05458@ladder01.news.aol.com> drasaul@aol.com (Dr
A Saul) writes:

>The human body does not have a clue what to do with Crisco.  Trans fatty acids
>are not really a natural form, as the cis- forms are.


  Every cis fatty acid is racemerized to trans before oxidation in
mitochondria.  The idea that the body has "no idea" what to do with
these things is an urban myth.  The strange thing is that this myth is
spread by professionals, too.  I can only conclude that there is real
deficit in biochemical education, here.

   Back to the textbooks, folks.

                                   Steve Harris, M.D.

From: sbharris@ix.netcom.com(Steven B. Harris)
Newsgroups: sci.med.nutrition
Subject: Re: hydrogentated oil
Date: 17 Jan 1998 11:24:53 GMT

In <1902.321T724T623744@escape.ca> "Syd Baumel" <sgb@escape.ca> writes:

>>In <19980117010500.UAA05458@ladder01.news.aol.com> drasaul@aol.com (Dr
>>A Saul) writes:
>>
>>>The human body does not have a clue what to do with Crisco.  Trans
>>>fatty acids are not really a natural form, as the cis- forms are.
>
>Harris:
>>  Every cis fatty acid is racemerized to trans before oxidation in
>>mitochondria. The idea that the body has "no idea" what to do with
>>these things is an urban myth. The strange thing is that this myth is
>>spread by professionals, too. I can only conclude that there is real
>>deficit in biochemical education, here.
>>
>>   Back to the textbooks, folks.
>>
>>                                   Steve Harris, M.D.
>
>Steve, you might want to peruse those textbooks yourself ;-) The last
>time you made this point, I rebutted it as follows. Perhaps you missed
>it, because you didn't respond (or to one or two others making much the
>same point). Here it goes again:
>
>>In <34B6B3A9.20C198B6@xsite.net> bonecrkr@xsite.net writes:
>
>>>It's alot worse than that. Hydrogenation results in the production of
>>>trans fatty acids. These can't really be used by the body
>
>Harris:
>>   Nonsense.  Your body converts all cis acids to trans before
>>oxidizing them.  It certainly knows what to do with trans acids.
>
>Is this a textbook fact? Assuming it is, surely it's one thing for the
>body to know what to do with a trans fatty acid it's just created in a
>confined metabolic space, quite another, perhaps, for it to be able to
>cope with one that came in through the gut and may get incorporated
>dysfunctionally into cell membranes, block enzymes involved in
>EFA/prostanoid metabolism, or cause other mischief before those
>oxidizing enzymes get a chance to deal with it.




Comment:


    What kind of rebuttal is that?  You say trans fatty acids really
can't be used by the body, and somebody else says your body has no idea
what to do with Crisco  This is poppycock. The AIN/ASCN expert panel
(see second abstract below) says: "Biochemical data indicate that trans
fatty acids are subject to the same metabolic control mechanisms that
regulate the metabolism of saturated and cis-isomeric fatty acids."  If
you don't believe this, I suggest you look up their cites in this nice
recent review paper in the major US nutritional journal, and argue with
them, not me.  I'm not going to try to teach you biochemistry on the
net.

    As for effects on health, the jury is still out.  For every
chicken little saying that margarine kills 10s of thousands a
year, there is somebody more rationally pointing out that we
think this mainly because of epidemiologic studies showing that
margarine eaters die more often of heart disease.  But what's the
first thing doctors for the last 20 years have done with people
at risk for heart disease, or who have it?  Yep, put them on
margarine.  The correlation may well be the other way.  Perhaps
heart disease causes margarine.  The data don't exclude that.
Correlation does not guarantee causation the way we want it.  For
example, I'm sure the death rates for heart disease are higher in
hospital ICUs than at the beach, but these statistics don't argue
for going on vacation when you get your heart attack.

   Yes, I try to stay away from hydrogenated fats, until all the
data are in.  But the anguished things I've been hearing on this
forum about the subject really have no good scientific
justification at present.


                                  Steve Harris, M.D.
------------------------------------------------------


ABSTRACTS OF INTEREST


Am J Clin Nutr 1997 Oct;66(4 Suppl):1011S-1017S
Do trans fatty acids increase the risk of coronary artery
disease? A critique of the epidemiologic evidence.

Shapiro S

On the basis of metabolic and epidemiologic data it has been
claimed that trans fatty acid intake causes coronary artery
disease (CAD), with > or = 30,000 deaths/y in the United States
and a considerably greater number of nonfatal cases. The metabo-
lic evidence is still controversial; the epidemiologic
evidence is reviewed here. In most studies the likelihood that
CAD "caused" margarine use, rather than the reverse, was not
excluded. Uncontrolled confounding (particularly confounding by
indication) was ubiquitous. Selection bias conditional on margar-
ine use was common. The projection of 30,000 deaths/y is not
justified. If the metabolic evidence, when fully evaluated, is
deemed to be suggestive, then the question of whether trans fatty
acids are indeed harmful to human populations will be resolved
only by means of a randomized controlled trial.


Am J Clin Nutr 1995 Sep;62(3):655S-708S
Trans fatty acids and coronary heart disease risk. Report of the
expert panel on trans fatty acids and coronary heart disease.

This review critically evaluates the scientific data on trans
fatty acids and coronary heart disease (CHD) risk. Trans fatty
acids are present in a variety of foods but they contribute only
4-12% of total dietary fat intake (2-4% of total energy intake)
in the United States. The physical properties of trans fatty
acids are intermediate between cis and saturated fatty acids, but
a trans double bond is chemically less reactive than a cis double
bond. Biochemical data indicate that trans fatty acids are
subject to the same metabolic control mechanisms that regulate
the metabolism of saturated and cis-isomeric fatty acids.
Equivocal results have been reported in observational studies of
trans fatty acid intake and CHD because of numerous methodologic
limitations, including the difficulties inherent in quantifying
trans fatty acid intake. Studies in hamsters indicate that trans
fatty acids have a neutral effect on low-density-lipoprotein
(LDL)-receptor activity, LDL-cholesterol production
rate, and plasma LDL-cholesterol concentration. Other animal
studies show no differences in atherosclerosis incidence or
severity between diets containing hydrogenated and native vegeta-
ble oils. In clinical studies partially hydrogenated oils lower
total and LDL-cholesterol concentrations when substituted for
animal or vegetable fats rich in saturates but raise total and
LDL-cholesterol concentrations when substituted for the
unhydrogenated native oil. The effects of trans fatty acids on
high-density lipoprotein cholesterol and lipoprotein(a) concentr-
ations are unclear because of limited and conflicting clinical
data. Data supporting a relation between trans fatty acid
intake and CHD risk are equivocal compared with extensive data
from studies in  animals and humans linking saturated fat intake
to CHD. Additional research is needed to resolve questions about
the independent effects of trans fatty acids on plasma
lipoproteins and their mechanisms of action.



Am J Clin Nutr 1996 May;63(5):663-670
Position paper on trans fatty acids. ASCN/AIN Task Force on Trans
Fatty Acids. American Society for Clinical Nutrition and American
Institute of Nutrition.

This report addresses the current controversy about possible
health hazards of dietary trans fatty acid isomers, which are
created during hydrogenation of unsaturated fats to change their
textural properties and melting points. Estimates of intakes are
approximations based on limited data and problematic analytic
techniques. Major contributors in the diet are fried and baked
foods and margarine, in which partially hydrogenated vegetable
oils may replace fat sources richer in saturated fatty acids and
cholesterol. Consumption of trans fatty acids in the United
States has been relatively constant, and new food technologies
are yielding decreases in the trans fatty acid content of
commercially prepared foods. When intake of trans fatty acids (as
hydrogenated fat) is compared with that of saturated fat, total
and low-density-lipoprotein (LDL)-cholesterol concentrations in
blood are lower, but both trans fats and saturated fats increase
total and LDL concentrations when compared with cis fatty acids
or native unhydrogenated fat. Epidemiologic data are conflicting
with respect to cardiovascular disease outcomes. We cannot
conclude that the intake of trans fatty acids is a risk factor
for coronary heart disease nor can we expect that substituting
trans- for cis-containing fats will reduce the risk
of coronary heart disease. Few rigorous studies have dealt with
biomedical effects of trans fatty acids and possible mechanisms
relevant to human health and diseases. The nutrition labeling
issue is unresolved. The options, recommendations, and research
suggestions in this report should outline for nutrition
scientists the database needed before any new dietary
recommendations or changes in nutrition policy concerning trans
fatty acids can be made. The debate about trans fatty acids
should not detract from dietary recommendations to limit the
intake of saturated fat and total fat.

From: sbharris@ix.netcom.com(Steven B. Harris)
Newsgroups: sci.med.nutrition
Subject: Re: hydrogentated oil
Date: 27 Jan 1998 06:12:38 GMT

In <34CCB5A8.4AE6E0AA@bellatlantic.net> "David B. Sprouse, CSCS"
<Daven8r@bellatlantic.net> writes:

>Steven B. Harris wrote:
>
>> In <19980117010500.UAA05458@ladder01.news.aol.com> drasaul@aol.com (Dr
>> A Saul) writes:
>> >
>> >The human body does not have a clue what to do with Crisco.  Trans
>> fatty acids
>> >are not really a natural form, as the cis- forms are.
>>
>>   Every cis fatty acid is racemerized to trans before oxidation in
>> mitochondria. The idea that the body has "no idea" what to do with
>> these things is an urban myth. The strange thing is that this myth is
>> spread by professionals, too. I can only conclude that there is real
>> deficit in biochemical education, here.
>>
>>    Back to the textbooks, folks.
>>
>>                                    Steve Harris, M.D.
>
>  But isn't it true that trans-fatty acids are incorporated into the
>cell membranes of various cells throughout the body which then may have a
>corresponding negative effect on membrane fluidity?


   That is true, but it's true of saturated fats also.  And membrane
fluidity isn't all good and no bad.  It's more like the air pressure in
your tires.  For example, it seems to affect your immune response.  Is
the more immune response you have the better?  No.  There are
autoimmune problems all the way from arthritis to rarer stuff.  And
inflammation is part of the damage done by many infectious diseases--
in many cases more than the organism itself does.  Do you know what
they give small children with meningitis, for example, besides
antibiotics?  Steroids.  If they don't, the immune response itself
causes brain damage.

                                      Steve Harris, M.D.

From: sbharris@ix.netcom.com(Steven B. Harris)
Newsgroups: sci.med.nutrition
Subject: Re: Transfats and Hydrogenation?
Date: 18 Mar 1998 06:57:07 GMT

In <6emtgm$bqv@bgtnsc03.worldnet.att.net>
<andrea-chad@worldnet.att.net> writes:

>I've read on many product packages the term "hydrogenated" and I've also
>heard the term in connection with what have been called trans-fats. Are
>these bad for you and what process is used to "hydrogenate" the things I
>eat?

   They heat the unsaturated plant oils up to high temps with hydrogen
and a nickel catalyst.  Thus turns it to saturated product, which is
solid at room temp (fewer kinks in the molecules, so they lie up
against each other more easily, and freeze).  Some of the natural fat
(which is all cis-double bonded in oils) is converted to trans
unsaturated substances by a side reaction.  This stuff raises
cholesterol worse than saturated fats, and should be avoided.  Don't
eat foods which have partially hydrogenated soybean or cottonseed oil
as first, second, or third ingredients.  By the time you get to 4th or
5th place on the label (they are always listed in order of amount),
you're not talking about enough to hurt you, generally.

                                          Steve Harris, M.D.

From: "Steve Harris" <SBHarris123@ix.netcom.com>
Newsgroups: sci.med.nutrition
Subject: Re: partially hydrogenated oils
Date: Sun, 22 Apr 2001 22:36:29 -0600

Somebody writes:

> > First of all, Trans-fatty acids naturally occur in nature.  Cavemen
> > supposedly consumed 2% of their diet in the form of Trans-fatty acids.

I find this hard to believe, since the things are made naturally mostly by
bacteria (such as exist in a cow's gut), which means they turn up
"naturally" in the diet mostly through dairy fats. Were these the well-known
dairy farmer cheesemaking cavemen? <g>



Steve Harris

From: "Steve Harris" <sbharris@ix.RETICULATEDOBJECTcom.com>
Newsgroups: sci.med.nutrition
Subject: Re: trans fats
Date: Tue, 19 Feb 2002 16:14:46 -0700
Message-ID: <a4umpl$2i3$1@slb4.atl.mindspring.net>

"AlanL" <alan@nospam.com> wrote in message
news:a4u4e1$tgb$1@iruka.swcp.com...
> In article <a4m1mp$5lb$1@wildfire.prairienet.org>,
> Jean P Nance  <jpnan@bluestem.prairienet.org> wrote:
> >
> >Our newspaper yesterday had an excellent article on trans fats. It calls
> >them "hidden fats" because it is not required that they be listed in the
> >nutritional information on packages. I had been in the practie of noting
> >the "total fat", then subtracting from  that the listed fats in the
> >required categories, Frequently, there is a discrepancy, and I could only
> >assume that the difference represented trans fats. Apparently, I was
> >right. Those who want to eat only "healthy" fats must do some arithmetic
> >to find the amount per serving of the "hidden fat", which is trans fat and
> >should be avoided.  [ ... ]
>
> I've heard that frequently trans-fats are lumped
> in with saturated fats, so even arithematic may
> not help.

As a first pass, you can simply avoid anything with "partially-hydrogenated"
on the label. As a second pass, you have to avoid milk fat as well.  But
since there are other reasons to avoid most milk fat, that's okay.  The
possible exception is cheese. It contains some natural trans-fats, but
doesn't show up too badly in the epidemiologic studies. So if you're going
to eat these things, eat them as part of this food.

Otherwise, don't!

From: "Paul Rogers" <consult@imagic.com.au>
Newsgroups: sci.med.nutrition
Subject: Re: partially hydrogenated oils
Date: Mon, 23 Apr 2001 01:37:30 GMT

"Quentin Grady" <quentin@paradise.net.nz> wrote in message
news:8944etsg8rpqf753ckk7d3gfe4healf1sj@4ax.com...

> Here is a quotation from a flyer for a book on modern food.
>
> "The impact of trans fat has only just been understood, following an
> American study of some 80,000 women, which found that a 2 per cent
> increase in trans fats increased a woman's heart-disease risk by 93
> per cent. Compare this with the old enemy, saturated fats: the same
> study found that a 5 per cent increase in saturated fats increased the
> heart disease risk by 17 per cent. It seems tame compared with the new
> stuff."
>
> You can read the full article at,
> http://smh.com.au/news/0104/04/features/features8.html

Quentin, Here is the paper:

--------------------->
N Engl J Med 1997 Nov 20;337(21):1491-9 Related Articles, Books, LinkOut
Dietary fat intake and the risk of coronary heart disease in women.
Hu FB, Stampfer MJ, Manson JE, Rimm E, Colditz GA, Rosner BA, Hennekens CH,
Willett WC.

Department of Nutrition, Harvard School of Public Health, Boston, MA 02115,
USA.

BACKGROUND: The relation between dietary intake of specific types of fat,
particularly trans unsaturated fat and the risk of coronary disease remains
unclear. We therefore studied this relation in women enrolled in the Nurses'
Health Study. METHODS: We prospectively studied 80,082 women who were 34 to
59 years of age and had no known coronary disease, stroke, cancer,
hypercholesterolemia, or diabetes in 1980. Information on diet was obtained
at base line and updated during follow-up by means of validated
questionnaires. During 14 years of follow-up, we documented 939 cases of
nonfatal myocardial infarction or death from coronary heart disease.
Mutivariate analyses included age, smoking status, total energy intake,
dietary cholesterol intake, percentages of energy obtained from protein and
specific types of fat, and other risk factors. RESULTS: Each increase of 5
percent of energy intake from saturated fat, as compared with equivalent
energy intake from carbohydrates, was associated with a 17 percent increase
in the risk of coronary disease (relative risk, 1.17; 95 percent confidence
interval, 0.97 to 1.41; P=0.10). As compared with equivalent energy from
carbohydrates, the relative risk for a 2 percent increment in energy intake
from trans unsaturated fat was 1.93 (95 percent confidence interval, 1.43 to
2.61; P<0.001); that for a 5 percent increment in energy from
monounsaturated fat was 0.81 (95 percent confidence interval, 0.65 to 1.00;
P=0.05); and that for a 5 percent increment in energy from polyunsaturated
fat was 0.62 (95 percent confidence interval, 0.46 to 0.85; P= 0.003). Total
fat intake was not signficantly related to the risk of coronary disease (for
a 5 percent increase in energy from fat, the relative risk was 1.02; 95
percent confidence interval, 0.97 to 1.07; P=0.55). We estimated that the
replacement of 5 percent of energy from saturated fat with energy from
unsaturated fats would reduce risk by 42 percent (95 percent confidence
interval, 23 to 56; P<0.001) and that the replacement of 2 percent of energy
from trans fat with energy from unhydrogenated, unsaturated fats would
reduce risk by 53 percent (95 percent confidence interval, 34 to 67;
P<.001). CONCLUSIONS: Our findings suggest that replacing saturated and
trans unsaturated fats with unhydrogenated monounsaturated and
polyunsaturated fats is more effective in preventing coronary heart disease
in women than reducing overall fat intake.
--------------------------------->

Can't see the 93% though, and the analysis seems not so good at SMH.
Schlosser's book, apparently a good read, is a best seller in the US.

Paul R

From: "Steve Harris" <SBHarris123@ix.netcom.com>
Newsgroups: sci.med.nutrition
Subject: Re: partially hydrogenated oils
Date: Tue, 24 Apr 2001 20:42:54 -0600

"Quentin Grady" <quentin@paradise.net.nz> wrote in message
news:tssbetsjaomlrnu6mg095u01kq5nob534o@4ax.com...
> This post not CC'd by email
>  On Mon, 23 Apr 2001 01:37:30 GMT, "Paul Rogers"
> <consult@imagic.com.au> wrote:
>
> G'day G'day Paul,
>
>   OK.  I'm puzzled re your comments at the end of your post.
>
> "The relative risk for a 2 percent increment in energy intake from
> trans unsaturated fat was 1.93 (95 percent confidence interval, 1.43
> to 2.61; P<0.001)"
>
> A relative risk of 1.00 would imply a zero percent increased risk.
> A relative risk of 1.93 surely implies a 93% increase in risk.
> What if anything am I missing?
>
> Is it that the increased risk could vary from 43% to 161% with the 93%
> figure being the most probable?


Your last guess is correct.