 | Health Risks from Processed Foods and Trans Fats: Part II |
| Interview with © Dr. Mary Enig | |
as Interviewed By© Richard A. Passwater Ph.D.Mary G. Enig, PH.D., a nutritionist widely known for her research on the
nutritional aspects of fats and oils, is a consultant, clinician, and the
Director of the Nutritional Sciences Division of Enig Associates, Inc.,
Silver Spring, Maryland. She received her PhD in Nutritional Sciences from
the University of Maryland, College Park in 1984, taught a graduate course
in nutrient- drug interactions for the University's Graduate Program in
Nutritional Sciences, and held a Faculty Research Associateship from 1984
through 1991 with the Lipids Research Group in the Department of Chemistry
and Biochemistry. Dr. Enig is a Fellow of the American College of Nutrition,
and a member of the American Institute of Nutrition. Her many years of experience
as a "bench chemist" in the analysis of food fats and oils, provides
a foundation for her active roles in food labeling and composition issues
at the federal and state levels.
Dr. Enig is a Consulting Editor to the "Journal of the American College
of Nutrition" and formerly served as a Contributing Editor to "Clinical
Nutrition." She has published 14 scientific papers on the subject of
food fats and oils, several chapters on nutrition for books, and presented
over 35 scientific papers on food and nutrition topics. She is the President
of the Maryland Nutritionists Association, past President of the Coalition
of Nutritionists of Maryland and was appointed by the Governor in 1986 to
the Maryland State Advisory Council on Nutrition and served as the Chairman
of the Health Subcommittee until the Council was disbanded in 1988.
Last month we talked mostly about what trans fats (TFAs) were, how they
interfere with "machinery" of our normal cell biology and that
they are a recent and unnatural intrusion into our diets. In Part II, we
will look into the health problems caused by TFAs, and in Part III, Dr.
Enig will put the research on TFAs and other fats in perspective and give
us her thoughts on the pluses and negatives of the Health Food Industry
as seen from academia.
Passwater: You mentioned the your research was stimulated by the early investigations
of Drs. Fred Kummerow, George Mann and Edward Pinckney. What did you set
out to investigate and what have others added to these findings?
Enig: Much of the Trans- Fatty Acid (TFA) research that was accomplished
at the University of Maryland from 1977 to today was done to answer some
very basic questions. For example, we wanted to know how much TFAs people
were being exposed to. So during some of the early research, we measured
the amounts of TFAs in typical U. S. foods and then estimated the amounts
in various diets and in the food supply.
The next set of efforts was done to measure the effects that feeding diets
containing physiologically relevant amounts of TFAs to laboratory animals
had on some reproductive and lactation functions, on the alteration of membrane
properties, and on the consequent alteration of enzyme functions that had
physiological importance. These different efforts were measured by our research
group, and many of our findings, e. g., that the enzyme functions were adversely
affected, were repeated by various other research groups. It is hard to
tell sometimes if we were repeating the findings of others or if others
were repeating our findings. I think it is safe to say that the research
was invariably reproducible as long as the same animal model and the same
amount of TFAs were used. In other words, our findings were real and other
researchers could easily find the same thing.
A number of research groups were able to use some of our basic findings,
and many of the researchers were using their own models and their research
was providing information that was parallel and complementary to ours. In
many instances, the other research teams had access to better funding and
models that we did not have at the University of Maryland.
One research group at Auburn University examined diets of adolescent girls
and directly measured the TFAs in their diets by laboratory analytical methods.
[16, 17] They found that approximately two- thirds of the TFAs in the diets
of these adolescents could be predicted by the food composition data in
our 1983 research paper for 220 foods. This is rather remarkable since their
research was done in another part of the country. It does show the similarity
of many of the same types of partially hydrogenated fats in diets across
the U. S.
A research group at Louisiana State University studied, among other things,
the effects of TFAs on what is called "the second messenger,"
cyclic AMP and the digitalis receptor. [18] They found that TFAs affected
both.
Still another research group, this one at Virginia Polytechnic Institute,
studied the effect of TFAs on bone development. [19, 20] Their research
showed some very undesirable effects! AS far as I know, the latter two groups
who were finding important effects have not been able to continue because
of lack of funds for TFA research. Their efforts were done independent of
our concerns and findings but parallel to our efforts.
There have been a number of other research efforts that have been given
widespread publicity. These include the published findings from Dr. Martijn
Katan's lab in Holland that the TFAs lower the "good" High- Density
Lipoprotein (HDL) and raise the "bad" lipoprotein [a] (Lpa) which
is atherogenic. [21] Also, the published findings from Dr. Walter Willett's
research at Harvard on 85,000 nurses, as well as other prospective studies,
have showed that those people who consumed the most TFAs had the most heart
disease. [3] Dr. Willett's group also has preliminary, as yet unpublished,
data that those individuals who developed breast and prostate cancer had
higher intakes of TFAs. These findings have been presented at scientific
meetings by Dr. Willett and his staff.
I have recently prepared a technical report which includes additional information
that would normally not be found in typical scientific reviews. [22] This
information is of special interest to many in the food industry and the
regulatory agencies. The report identifies all of the different research
groups that have been working on TFAs around the world over the past 60
years.
Passwater: I remember how the processed food industry tried to suppress
your early research. As Rodney Leonard, the editor of Nutrition Week noted,
you fought tenaciously to bring out the truth and were "a burr under
the saddle of the [processed food] industry and the government, persistently
challenging the contention that the health threat of trans fatty acids is
overplayed and that the current level of consumption poses no threat to
public health." Most of those who were skeptical then have examined
the steady stream of new data and now agree with you that TFAs are a major
health threat. How were you able to keep on? What techniques were used against
you and how did you overcome them? Where did you find moral and scientific
support?
Enig: As you know from some of our past conversations, we ran into some
strong challenges from certain segments of the edible oil industry regarding
our findings. In addition to writing several articles to "refute"
our findings, and seeing to it that our major reports did not get properly
referenced, those individuals who actively opposed our research were able
to influence funding sources. Gradually though, other researchers started
to realize that we were correct and appropriately conservative in our approach
to research, and consequently, most of the "bad- mouthing" that
we encountered has backfired.
Passwater: Yes, I remember well how we were both encountering difficulties
with "the establishment." I am happy to note, as you well know,
that the same is happening regarding my findings regarding vitamin E and
the prevention of heart disease, and of the antioxidant nutrients in the
prevention of cancer. We never did get the funding needed to further pursue
our research.
Enig: You're right. At the University of Maryland we never did get the type
of funding that you need to receive to continue the level of research that
would have been desirable, but what funding we did receive was carefully
managed and many of the people in our research group were dedicated to the
research.
I think we found moral support because we knew we were scientifically correct,
and ultimately the scientific support came as other researchers started
to evaluate the problems without having certain industry people set up their
research protocol. AS you realize from your years of involvement in research,
good research properly done is always reproducible, if all the variables
are the same, but it is also possible for unscrupulous individuals to set
up a research protocol designed to obfuscate, and if that gets published,
it keeps other good researchers from continuing to work in the area. Frequently,
those individuals who are coopted write their summary and abstract the way
the industry wants them to, but they usually leave their data intact so
that a knowledgeable researcher can recognize the inconsistency. However,
it is a very time- consuming task to constantly challenge each piece of
misinformation that you see.
Passwater: Yes, it is a difficult task, but you and I give it our best shots.
In the past we did a lot of challenging others to prove us wrong, and now
we can smile a lot.
Enig: Our work is not done yet! There is still much to do.
Passwater: Right again! How big is the problem with TFAs? How extensive
are trans fats in our modern diets, and how does this compare to ancient
diets and other diets around the world.
Enig: Today the levels of TFAs vary around the world from practically zero
to levels much like those found in our foods in the U. S. It depends on
how much partially hydrogenated vegetable fats or partially hydrogenated
marine oils are present in the food supply.
Without the commercial partial hydrogenation process, as would have been
the case more than a hundred years ago, the levels of TFAs in diets would
be relatively low. Only the ruminant fats would have supplied any, and the
types of isomers that are found in the ruminant fats behave in a very different
way from those found in the partially hydrogenated vegetable oils. Additionally,
the research shows that the TFAs are more of a problem when the level of
saturated fat is low. Diets that are higher in ruminant fats are also higher
in saturated fats. Most ruminant fats have about 2- 3% TFAs whereas the
partially hydrogenated vegetable fats are commonly 30- 40% and as high as
53% in foods in this country.
After analyzing hundreds of food samples for TFAs, chemically analyzing
food composites, and calculating dietary information, I am confident that
there are many people in this country who consume 20% of the total fat in
their diet as TFAs. On average though, 10.9% is the number we came up with
when we looked at all of the published analyses. The typical french fried
potatoes are around 40% TFAs, and many popular cookies and crackers range
from 30 to 50% TFAs, and every donut I have analyzed has about 35 to 40%
TFAs. Since these are all fairly high fat products, someone who eats a lot
of these types of foods will get a large amount of TFAs. Several years ago,
we documented nearly 60 grams of TFAs in someone's typical daily diet.
Passwater: Wow! I hope that's no one I know. Dr. Enig, you mentioned that
TFAs are atherogenic - - that is they cause atherosclerosis. Then you mention
that TFAs are more of a problem when saturated fats are low. Yet most people
fear saturated fats because they have been told that it is the saturated
fats that cause heart disease.
You are recognized as a leading expert on fats and oils, do saturated fats
cause heart disease?
Enig: The idea that saturated fats cause heart disease is completely wrong,
but the statement has been "published" so many times over the
last three or more decades that it is very difficult to convince people
otherwise unless they are willing to take the time to read and learn what
all the economic and political factors were that produced the anti- saturated
fat agenda.
Periodically, various reports have come out that show the inconsistencies
in the theory. You have already discussed this with the well- known cholesterol
and lipids researcher, Dr. David Kritchevsky of the Wistar Institute. [23]
In 1977, Dr. Kritchevsky noted that it did not make any difference what
kind of fat was added to the whole foods diets in animal studies - - only
when the diets were very unnatural chemically could changes be brought about
- - and from study to study these changes were inconsistent. [24]
As you frequently report, the latest theories regarding heart disease point
to oxidized fats and oxidized lipoproteins as culprits. This being the case,
accusations against chemically- stable, basically non- oxidizable saturated
fat don't make sense. Most people who find fault with saturated fats do
not really understand that our cells are busy making saturated fatty acids
all the time from carbohydrates and excess protein.
Passwater: Do tropical oils cause heart disease?
Enig: No they don't. Several studies have shown that there is no increase
in heart disease in countries or communities where most of the fat is either
coconut oil or palm oil. Palm oil that is not extensively refined has very
high levels of antioxidants, and coconut oil has high levels of very useful
medium chain fatty acids. There are many older research studies that showed
that adding quite a bit of coconut oil to the diet of persons having high
blood cholesterol reduced their level of cholesterol. Dr. George Blackburn
from Harvard Medical School has written an extensive review on this topic.
[25]
It is unfortunate that this misinformation about these oils became so widespread
because they are very stable oils that have unique functional properties
and products made with them as the fat component usually have far less fat
and therefore fewer calories. Needless to say, they would also have virtually
no TFAs which are unquestionably atherogenic. When coconut oil was used
in the manufacture of crackers, very little fat was added to each cracker,
but the crackers did not become stale before they could be purchased. Now
the fat- free crackers become very stale very quickly, and the crackers
made with the more unsaturated oils are higher in fat and are greasy or
they appear drier because they are made with the high- temperature melting
partially hydrogenated oils. Deep fried foods made in these oils never absorb
quite as much fat as they do when they are fried with the more unsaturated
oils.
Passwater: Speaking of deep fried french fries, I notice that the Community
Nutrition Institute is pleading with McDonald's to go back to their old
cooking oil, an animal tallow. CNI cited higher risks of coronary heart
disease, coronary artery disease, and low birth- weight babies due to the
partially hydrogenated vegetable oil that McDonald's has been using since
1990. [26]
Enig: Yes, when I analyzed the oils, I found that the percentage of fat
that was saturated fat in their french fries dropped from 49% to 24% when
McDonald's switched from animal tallow to partially hydrogenated vegetable
oil. But the percentage of fat that was TFAs rose from 5% to 42- 48%. McDonald's
own study showed that the total amount of fat in its fries rose from 17.6%
to 27.9% Recently, McDonald's has again switched to an oil that has cut
the TFAs in half. But, those who insist on eating french fries were better
off when the beef tallow was used.
Passwater: Why were earlier researchers misled about saturated fats and
heart disease?
Enig: The simplistic, abbreviated story of how some of the anti- saturated
fat rhetoric got started and then took a strangle hold, is that when laboratory
animals were fed semi- purified and artificially saturated (fat) diets,
the animals actually became deficient in essential fatty acids. As a result,
these animals developed lesions that were incorrectly defined as the equivalent
of heart disease. This "research" was touted as showing an effect
of "saturated" fat. Then when Dr. Ancel Keys of the University
of Minnesota reported that hydrogenated fats were responsible for heart
disease [15], the response from the threatened edible oil industry was to
claim that it was only the saturated fats that were the culprits, and that
the industry would get rid of the problem by only partially hydrogenating
the oils. From that point on, the saturated fats stood "guilty as accused,"
even though study after study showed that there was no relationship between
saturated fat intake and the development of heart disease.
In fact, some of the studies showed that there was less progression of the
disease process when the saturated component was higher. [27] Usually the
proponents of the lipid hypothesis managed to squelch the effect of these
reports. Of course the partially hydrogenated oils were really very little
different in saturated fat level than the fats and oils that had been called
"hydrogenated," but the public and the media and many of the naive
researchers didn't know that.
As time went on, the whole heart disease agenda became a multi- million
dollar business that was benefiting the researchers funded by the part of
the National Institutes of Health that deals with heart disease, the National
Heart, Lung and Blood Institute. The only people not benefiting were and
are the consumers who are continuing to get more and more heart disease
at higher and higher costs. The consumer may not be dying from heart disease
as often as they were 30 years ago, but they are undergoing more surgery
such as by- pass and angioplasty, and they are swallowing more expensive
cholesterol- lowering drugs. All in all, while the so- called mortality
figures have decreased, the incidence has greatly increased.
Of course, the ill- trained consumer activist groups have added to the problem
by continuing to publish their own misinterpretations of the science, and
this in turn, is further publicized in the media.
Passwater: Well, I see that you haven't backed off and cow- towed to the
consensus pseudo- scientists that form opinions without looking closely
at the data. I would like you to explain the real facts and their proper
interpretation for the benefit of our readers. So let's look at fats and
cholesterol, TFAs and the obesity trigger, and your thoughts on helping
the Health Food Industry in Part III.
"Health Risks from Processed Foods and Trans Fats: Part III"
Mary Enig, Ph.D.
Interviewed by Richard A. Passwater, Ph.D.
Dr. Mary G. Enig, a nutritionist widely known for her research on the
nutritional aspects of fats and oils, is a consultant, clinician, and the
Director of the Nutritional Sciences Division of Enig Associates, Inc.,
Silver Spring, Maryland. She received her PhD in Nutritional Sciences from
the University of Maryland, College Park in 1984, taught a graduate course
in nutrient- drug interactions for the University's Graduate Program in
Nutritional Sciences, and held a Faculty Research Associateship from 1984
through 1991 with the Lipids Research Group in the Department of Chemistry
and Biochemistry. Dr. Enig is a Fellow of the American College of Nutrition,
and a member of the American Institute of Nutrition. Her many years of experience
as a "bench chemist" in the analysis of food fats and oils, provides
a foundation for her active roles in food labeling and composition issues
at the federal and state levels.
Dr. Enig is a Consulting Editor to the "Journal of the American College
of Nutrition" and formerly served as a Contributing Editor to "Clinical
Nutrition." She has published 14 scientific papers on the subject of
food fats and oils, several chapters on nutrition for books, and presented
over 35 scientific papers on food and nutrition topics. She is the President
of the Maryland Nutritionists Association, past President of the Coalition
of Nutritionists of Maryland and was appointed by the Governor in 1986 to
the Maryland State Advisory Council on Nutrition and served as the Chairman
of the Health Subcommittee until the Council was disbanded in 1988.
In the two previous issues, Dr. Enig and I have been discussing how the
trans fatty acids formed upon the partial hydrogenation of vegetable and
marine oils are being shown to be more harmful than saturated fats. Margarine
and other processed foods rich in Trans Fatty Acids (TFAs) were once touted
to be healthy choices for good diets, but now many researchers are recognizing
that TFAs are more harmful than the natural butter and animal or tropical
fats they replaced.
We discussed how the processed food industry tried to cover up this fact.
As Rodney Leonard discusses in Nutrition Week, "The reputation that
[hydrogenated] vegetable oil as the fat of choice in a healthy diet lies
in ruins. And the real question is why the American health establishment
did not act sooner to correct what may be the biggest scam ever perpetuated
in nutrition and nutrition policy on the American public...These trans fatty
acids were found to not only have more severe health consequences for persons
at risks for heart disease, but also to increase the risk for individuals
prone to certain types of cancer." [28]
We have let our natural diet be changed by processed food technology. The
European Community has decided to limit TFAs to four percent of the energy
source. Unfortunately, as Dr. Enig has shown, the American diet is closer
to 10 - 14 percent, with some individuals consuming as much as 60 grams
of TFAs daily. Let's continue to look into the trumped- up reasons given
to us by food processors as why we should switch to TFAs, and then see what
the truth is.
Passwater: Some "authorities" are implying that all saturated
fats or animal fats greatly increase LDL cholesterol by shutting down LDL
receptor production which consequently causes LDL cholesterol to build up
in the blood, while they are also implying that all polyunsaturated fats
or vegetable fats either lower LDL cholesterol or raise it only modestly.
Would you share with us your perspective of what we can accept as fact about
saturated fat, monounsaturated fats, polyunsaturated fats and TFAs with
respect to blood cholesterol?
Enig: This is a complex subject, that is difficult to explain in a few words,
but I'll try to be brief. The current dogma on the effect of saturated fatty
acids on LDL and LDL receptors is really an issue that is not satisfactorily
clear- cut. It is not surprising that feeding different proportions of different
fatty acids have different effects in different animals and different organ
systems or tissues. Fatty acids are active components in regulating all
sorts of homeostatic mechanisms in mammalian systems. But sometimes some
of the basic research that identifies what is happening to one part of the
cell does not really show what is going on in another part of the cell or
in the whole person, and these reports have to be interpreted carefully.
I am concerned about the inconsistencies in interpreting the research. One
example of such inconsistency can be seen when you compare some of the research
with recent reviews. In a section of a 1980 report that measured the effect
of dietary fats on LDL- cholesterol in humans, i. e., the effect of saturated
and polyunsaturated dietary fat on the composition of LDL, the total cholesterol
in LDL from feeding saturated fat was 59.1% (balanced is phospholipid and
triglyceride) and the total cholesterol in LDL from feeding polyunsaturated
fat was 59.5%. Not very different and certainly not higher than from saturated
fat!
These data are from the research of Dr. Antonio M. Gotto's group at Baylor
College of Medicine. [29]
Given these findings, I have some real problems with the unreferenced or
inappropriately- referenced statements in, for example, the recent chapter
on regulation of LDL- cholesterol levels that appeared in the 1993 Annual
Reviews of Nutrition. The statement was made that "... {fats} containing
predominantly saturated fatty acids further increase the concentration of
cholesterol carried in [the LDL] fraction ..." and that "... when
fed at equal levels, saturated fatty acids are more active in increasing
the LDL- C concentration than are unsaturated lipids in reducing the concentration."
There was no reference given for the first part of the statement; the references
for the latter part (a 1957 paper by Dr. Ancel Keys et al and a 1989 talk
by Dr. Mark Hegsted) are really inappropriate in my opinion.
Passwater: I see that you still tell it like it is. My next question won't
be of interest to most of our readers, but I have to ask it because it will
be important to other researchers. So readers please hang on for a brief
moment while I get a tad technical, and then well get to the practical "take
home" message.
Dr. Enig, how about the LDL- receptor?
Enig: Briefly, so much of the research on down regulation of the LDL- receptor
appears to be done on cells like fibroblasts which are questionably appropriate.
One report showed that down regulation of LDL- receptors by saturated fatty
acids was considered a good phenomenon since the cell was a macrophage.
In addition, any of the changes that are occurring in response to short-
term feeding that are likely to be rearrangements of homeostatic mechanisms
don't mean very much. I know that many feeding studies have been purposely
cut off after a short term so that it would show something that would not
show up in the long term.
As I said, I think this very complex area probably needs a whole article
that delves into the meaning of the inconsistencies. Many people have interpreted
these reports as meaning that people should avoid saturated fatty acids
and consume more polyunsaturated fatty acids. It is important to know that
historically no people had a high intake of polyunsaturates in their diets.
This is really a phenomenon of the present century, and the evidence against
the excess intake of polyunsaturates is mounting.
Passwater: Its ironical - - animal fats have been blamed for the damage
caused by partially- hydrogenated oils - - which started out as wholesome
vegetable oils - - that is, until they were chemically altered by man. I
can't help but think about so many in the general public who are not scientifically
trained and who have been brain- washed by the countless illegal commercials
that promise that using margarine will protect them from heart disease.
These people don't even read the newspaper accounts such as the report from
Harvard that margarine actually is associated with increased heart disease
and heart disease death. In the Harvard study of 85,000 nurses, after adjusting
for all known possible confounding factors including total fat and total
calorie intake, there was a fifty percent greater incidence of heart disease
among those women with consuming the highest fifth of percentage of fats
as TFAs compared to those in the lowest fifth. [3] Since all other factors,
including total fat and total calories were compensated for, the researchers
conservatively concluded, "these findings support the hypothesis that
consumption of partially- hydrogenated vegetable oil may contribute to occurrence
of coronary heart disease."
Then there is the recent report in the American Journal of Clinical Nutrition
that found that the risk of coronary heart disease increases as consumption
of vegetable oil rises. [30]
However, the years of newspaper, magazine and TV ads that falsely told them
that margarine was good for the heart - - has made them think that it was
true.
Now we are learning that mothers are giving their children soda or skim
milk with their meals so as to avoid the fat in milk. They want to protect
their children against heart disease by giving them very low fat diets in
their youth. What effect is the fear of saturated fat having on the health
of our children?
Enig: It is really unfortunate that children are being encouraged to drink
low- fat milk instead of whole milk. In addition to the fact that milk is
a good source of calories for growth (children actually need fat as an energy
reserve so that the protein they are consuming can be well utilized for
growth), there are a number of components in milk that are not widely appreciated.
Milk fat globule membrane has anti- cancer properties and some of the fatty
acids found in milk (and coconut oil) have anti- microbial properties.
Passwater: I am seeing reports that there appears to be a link between TFAs
and obesity? Dr. Lewis H. Kuller has made such comments in Lancet, and Drs.
Edward Siguel and Robert Lerman have indicated such a possible link in the
American Journal of Cardiology. [31,32] I have also read discussions where
TFAs have been called "the obesity trigger."
Enig: There was a report earlier this year at a major symposium on obesity
that was held in New York, that the metabolic effect of increasing dietary
TFAs changes characteristics of muscle cells that trigger the onset of diabetes
and increasing obesity. I have not seen the actual research, but am looking
forward to following it.
Passwater: Dr Enig, many of our readers are hearing about trans fats for
the first time. Others may not be sure of what your message is regarding
red meat, animal fat and vegetable oil. Would you give us a "take home"
perspective regarding your advice on dietary fats?
Enig: The important thing to understand is that all fats are basically mixtures
of saturated, monounsaturated and polyunsaturated fatty acids in different
proportions. There isn't any real evidence that everyone needs to consume
exactly the same balance of fatty acids, except that we do know that people
need to take in at least 2- 3% of their fat as the omega- 6 fatty acids
and at least 1- 1.5% of their fat as omega- 3 fatty acids. This means that
smaller people expending fewer calories need fewer calories of each fatty
acid and total fats than larger or more active people who consume more calories.
The fats that humans have consumed for millennia, such as the fats they
added to mixed dishes, were almost always more saturated than they were
unsaturated. It was the easily extractable fat or oil. The fat came from
the animal, or, in the case of areas such as the tropics, it was the oil
that came from the coconut or the palm fruit that was used in cooking. Sometimes
it was one of the very stable oils such as olive oil or sesame paste that
contained lots of built- in antioxidants and weren't too polyunsaturated.
People didn't really have the ability to extract oil from vegetables such
as corn, or from many seeds as they do today. However, they got their essential
polyunsaturated fatty acids from many of these plants when they were included
in the foods they were eating. People used the intact leaf, root, nut, grain
or seed along with all their antioxidants in the stews or the porridges
that most people ate. This was the manner in which the polyunsaturates were
historically consumed. The polyunsaturated fatty acids didn't have to be
hydrogenated to protect their integrity and keep them from going rancid
because they were consumed in a protected whole- food state.
People on low- fat diets historically consumed adequate amounts of essential
fatty acids from foods such as grains, vegetables and nuts; and then they
made their own saturated fat for the necessary structural adipose (structural
body fat) and energy storage. Those people with higher fat intakes in their
diets still had about the same amount of essential fatty acids, and ultimately
the same amount of saturated fat for storage or as the energy source. Regardless
of whether they ate it or made it, the fat in the tissues of our ancestors
was relatively saturated, and therefore, the fatty acid supply to the tissues
was predictably saturated. Today, with the high levels of partially- hydrogenated
vegetable and marine oils in the diets of many people, the tissues and organs
are faced with a new situation. Many researchers have now concluded that
the presence of the TFAs is causing shifts in favor of chronic disease.
Not a good situation!
The bottom line is to consume as many whole foods and whole food mixtures
as possible. Since we live in a society where other people prepare most
of the foods many of us eat, it is important to look for the least processed
and the least likely to go rancid when it comes to fats and oils.
There is nothing wrong with consuming your essential fatty acids from oils
as long as those oils are safely extracted and carefully stored, but a good
balance needs to be maintained with sources of the more saturated fats such
as the animal tallows and/or dairy fats for those who are not vegetarians,
or the more saturated fats such as palm or coconut oils for those who are
vegetarians.
Passwater: These facts will be hard to accept by those who have always heard
just the opposite, and because of this constant repetition, they have come
to believe the erroneous information. While we're on the subject of truth,
let's shift gears for a moment.
You attended the Waxman hearing in July. What comments do you have to offer
about the FDA efforts to limit nutritional products and information?
Enig: One major problem as I see it is that the members of congress and
their staffs have only part of the information and almost none of the training
to understand that the FDA is running with misinformation a lot of the time.
But, if it suits their agenda, they will vigorously use it.
The supplement industry needs to be sure of its facts, needs to spend the
time and effort to document these facts. The science is on the side of whole
foods and rational supplementation. There is one thing that bothers me;
as an expert in lipids I notice mistakes in many books, magazines and newspapers
being made by "spokespersons" about the effects of fats and oils
in health. I immediately discount the reliability of source of the information
and suspect anything else that is being said. Sometimes I make allowances
and can salvage certain facts and separate the wheat from the chaff, but
others not so inclined, might not be so lenient. Since the FDA has a very
biased attitude towards the whole foods and supplement industry, any erroneous
written material that is put out by that industry or on behalf of that industry
is considered grist for the FDA's mill. I hate to see the good apples spoiled
because of the presence of a few rotten ones.
Passwater: There is so much that needs to be covered, and we didn't even
get around to discussing omega- 3 and omega- 1 fatty acids. Perhaps you
will be kind enough to chat with us again. I am sure that TFAs cause membrane
abnormalities that can cause irregular heart beats and I want to pursue
the research that suggests that TFAs trigger obesity. We are going to hear
a lot more about TFAs in the future. It has taken 15 years, but I feel that
the corner has now been turned and the momentum is building. The data can
no longer be suppressed.
Your pioneering studies will have a major impact on helping people select
better diets in the future. Now the public will have to deal with the fact
that most junk foods are high in trans fat - - and this is a deadly reality
that can not be compensated for merely by juggling other food components.
Changing the ratio of polyunsaturates or saturates does not alter or compensate
for the accumulation of trans fats. People will no longer be able to rationalize
junk food as "just" being devoid of nutrients which can be replaced
with supplements. People will no longer be able to rationalize junk food
as "just" being high in fat which can be held in check by keeping
the total dietary fat to 30% or less of total calories by selecting low-
fat high- sugar foods. The reality is that there are only two healthy choices
- - either get the trans fats out of foods and pseudo foods such as margarine
- - or don't eat them. At least we can control the latter.
Dr. Enig, what are you looking into now?
Enig: I have submitted a proposal for a research project that aims to evaluate
a specific nutritional support approach that I think will be extremely useful
for individuals with HIV/AIDS. I am currently waiting to hear about the
funding. I am presently preparing some of the research done by our group
at the University of Maryland for submission to the appropriate scientific
journals. I am also writing articles and a book aimed at correcting a lot
of the misinformation that has been written about fats and oils. The working
title of the book is "Know Your Fats: The complete primer for understanding
fats, oils and cholesterol." The book is meant to be a comprehensive
primer that would accurately explain what I have realized most people involved
in nutrition don't really understand. I am also teaching short courses and
workshops on lipids and nutrient- drug interactions. I fell that there is
a great need for people with my training to continue to teach and consult.
Passwater: And, I am sure that you will continue to speak out for scientific
truth. I can hardly wait for your book to be published. Thanks for taking
the time to inform us about the dangers of trans fats in processed foods.
I still admire your bravery in presenting the information in scientific
forums, rather then taking the easy path of merely researching topics that
are "politically" safe and don't risk losing funding or dirty
tricks. I have always enjoyed our nutrition discussions through the years
and look forward to more of your visits to the Solgar Nutritional Research
Center.
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All rights, including electronic and print media, to these articles are copyrighted
to © Richard A. Passwater, Ph.D. and Whole Foods magazine (WFC Inc.).
| Related Articles | About The Author Richard A. Passwater, Ph.D. has been a research biochemist since 1959. His first areas of research was in the development of pharmaceuticals and analytical chemistry. His laboratory... ...more |
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