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I never can resist a chance to
emphasize the fact that long ago there was a group of knowledgeable nutrition
experts saying all the things that are now being presented with such
fanfare as new discoveries. This is, therefore, a slightly
up-dated version of a column I wrote for our local paper
approximately fifteen years ago: you have my permission to be astonished
by my prescience.
At its simplest, my belief is
that the the more
someone else's hand has interfered with your food between its
original state and your mouth, the less likely you are to benefit
from eating it. I mean that if you buy an ur- food, and cook it
yourself, you know what you are getting. If it has been processed
and sold to you as a completed product, odds are the motivating
factor in what has been done to it is not your health, but the
bottom line of the food manufacturer.
Forgive my cynicism here, but
I have yet to see a food that has benefited nutritionally from being
processed. As an example, I have ALWAYS recommended butter over margarine
(I make my own), I
use lard (which I render myself) sparingly in my kitchen ,
and the role of coconut oil in the impressive health record of the
indigenous populations who use it cannot be argued. Once again let
me emphasize my 2 credos and apply them to fat selection:
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lack of moderation causes
imbalances: choose good fat sources and use them in
moderation.
-
technology in food is usually
the enemy: choose the fats that have been used traditionally
in healthy cultures and you can't go much wrong.
While this may not sound terribly
scientific, it is my recommendation for relaxed maintenance of a
healthy fatty acid balance.
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Essential Fatty Acids are required for
energy
production in the body, for cardiac function, for the
health of hair, skin and nails, for hormone production, brain
function, and (extremely important) for the integrity of the very structure of our cells.
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Fat is the major form of energy storage. In a
typical individual the fuel reserves are distributed as follows:
Fat: 100,000 kcal.
Protein: 25,000 kcal.
Carbohydrate: 650 kcal.
However, one can't just say "fat", because it is
becoming increasingly apparent that the KIND of fat is crucial to
health. Mono-unsaturated fatty acids convert to energy much more
efficiently than saturated fats (the subject of a study sponsored by
the National Institute of Diabetes and Digestive and Kidney Diseases
(NIDDK) - see RESOURCES at right).
Fat molecules are made up of three fatty
acid chains connected by a glycerol backbone. Fatty acids are
basically long chains of carbon and hydrogen, which are broken down
by progressively cleaving two carbon bits and converting these to
acetyl coenzyme A. For every two carbons in a fatty acid, oxidation
yields 5
ATPs
(measures of energy) , but
saturated fats have been converted to chains of hydrogen only, which
oxygen cannot break to produce energy.
Below are sources of fatty acids:
| Name of acids |
Rich sources |
| Saturated
|
| Palmitic |
All fats and oils |
| Stearic |
Lards, tallow , coconut |
| Butyric |
Butter |
| Unsaturated
|
| Oleic |
All fats and oils - olive,
macadamia, etc |
| Linoleic |
Mostly in vegetable oils like
sunflower, safflower, soya bean, corn, cotton seed and walnut
|
| Linolenic |
Linseed oil |
| Arachidonic |
Fish oils and animal fats |
Source
of table, with thanks.
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It therefore follows that
eliminating saturated, trans and hydrogenated fats from our diets
and replacing them with better choices
can make a vast difference to
our health |
I remember coming across a petition to
the FDA asking that some new studies on the connection between
hydrogenated fats and coronary artery disease not be disseminated,
for fear of causing consumers "unnecessary alarm"! These are the
Trans fatty acids found in such things as Crisco and some
margarines, so I don't think it's too much of a stretch to figure
out where the petition came from - hint: not a consumer protection
group. Now, it appears that trans fatty acids are
villains to our children (see below)
as well as to our cholesterol levels as adults (though this
shouldn't really come as such a surprise.)
Why is it important to limit trans
fatty acids? A report released by the Institute of Medicine on July
11th 2002 says it all: "It is recommended that trans fatty acid
consumption be as low as possible while consuming a nutritionally
adequate diet," a panel of experts stated, noting that trans fatty
acids are known to increase blood levels of low-density
lipoprotein, while lowering levels of high-density lipoprotein."
It is also important to note that trans fats block the enzyme
that converts the alpha-linolenic acid in flax oil to EPA and DHA.
WESTPORT, CT (Reuters Health) Jul 12
- A diet rich in foods containing trans fatty acids increases
concentrations of LDL cholesterol. However, unlike saturated fats,
trans fatty acids also decrease concentrations of HDL cholesterol,
which appears to significantly impair endothelial function, Dutch
researchers report.
"By measuring arterial vasodilation, we compared the effects of
trans fatty acids with those of saturated fatty acids to determine
whether the decrease in HDL cholesterol posed an additional risk of
cardiovascular disease," Dr. Nicole M. de Roos, from Wageningen
University, told Reuters Health.
In a randomized crossover trial, Dr. de Roos and colleagues put 29
healthy subjects on two controlled diets, according to their report
in the July issue of Atherosclerosis, Thrombosis and Vascular
Biology . The subjects consumed each diet, for 4 weeks. Both diets
contained 9.2 energy percent from either trans fatty acids
(Trans-diet) or saturated fatty acids (Sat-diet).
Dr. de Roos' group found that when subjects consumed trans fats
instead of saturated fatty acids HDL-cholesterol levels went down by
about 26% and arterial dilation was impaired by about one third.
"When patients consumed a diet containing saturated fats,
vasodilation was about 6.5% of baseline diameter, while it was about
4% of baseline diameter on the diet rich in trans fats," Dr. de Roos
said.
Given their findings, Dr. de Roos believes that "we should try to
ban trans fatty acids from our diets and replace them with natural
oils, before they are hydrogenated, or by tropical saturated fats
that are rich in C14, C16 fatty acids, which do not lower HDL
cholesterol."
Arterioscler Thromb Vasc Biol
2001;21:00-00.
Dr. Undurti Das has been studying EFA levels in
infants and corresponding rates of hypertension. He says that
when DHA levels are reduced in animal models the animals develop
hypertension as adults. There is also evidence that when these
fatty acids are given to adults who have mild to moderate
hypertension, blood pressure returns to normal, he added.
Because breastfeeding may not supply all the
polyunsaturated fatty acids needed to prevent hypertension, Dr. Das
hypotheses that hypertension could be prevented by supplementing the
child's diet with long-chain polyunsaturated fatty acids from birth
through early childhood.
"Intervention needs to be done early, because once
the neural mechanisms involved in the development of hypertension
are developed, prevention may be too late," he said.
The researcher recommends that a clinical study be
conducted with children who are supplemented with polyunsaturated
fatty acids from birth to about 5 years of age and are then followed
to see if hypertension develops.
These fatty acids prevent cardiac arrhythmias,
type 2 diabetes, and reduce the cholesterol and triglyceride levels,
he said. Polyunsaturated fatty acids also reduce the production of
harmful cytokines, such as tumor necrosis factor, interleukin 1beta
and interleukin 6, Dr. Das added. "Perhaps polyunsaturated fatty
acid supplementation should be given lifelong."
Hypertension
2001;38:e6-e8.
A team of Finnish
researches has found that the kind of fats
in children's diets may play a role in the increased
incidence of allergies. Their study found that children who
eventually developed allergies ate less butter and more margarine
compared with children who did not develop allergies. The
allergic children also tended to eat less fish, although this
dietary difference was not considered significant. This is not the
first study to indicate that polyunsaturated fats may play a role
in allergies: fats like those in margarine have been shown to
encourage the formation of prostaglandin E2, a substance that promotes
inflammation and causes the immune system to release a protein that
triggers allergic reactions.
Allergy 2001;56:425-428
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No, the fats that are essential to
our health, and that we need a supply of on a daily basis are unsaturated oils,
preferably a selection of poly- and mono
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A deficiency of unsaturated oils has been linked to a
long list of problems ranging from arthritis to MS to heart disease, high cholesterol levels
and cancer. The Omega-3 and Omega- 6 fatty acids
in proper balance play a vital part in normalizing many body functions: for example,
it has been shown that Omega-3 oils actually break down cholesterol
in the lining of the blood vessels, and facilitate the transport of
saturated fats, as well as lowering levels of LDL, the "bad" form of
cholesterol. They are also instrumental in preventing a
pro-inflammatory cycle which can be instigated by excessive intake
of the wrong kinds of fats and fatty acids. One problem with
achieving this balance is that the Omega 6 fatty acids are much
more common, being in most of the oils we use -such as corn oil,
which in effect is present in almost all processed foods. My
personal preference in mono-unsaturated or Omega 9s is for olive and macadamia
oils; Omega 9s are essentially neutral, where most cooking
oils are Omega 6s.
OMEGA-3 FATTY ACIDS
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Fats are essential to the health of
our cells. Restated, the PROPER fats are essential to the health
of our cells. The fats most prevalent in our diets, however, are
predominantly Omega 6, which are pro-inflammatory.
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Corn and
safflower oils, which are in practically everything in the way of
prepared foods, are Omega 6. What we need is to redress the balance to a
prevalence of Omega 3 fatty acids.
Sources of Omega 3 are
walnuts, flax and fish. When you consider that an enzyme
(deficient in many people, and especially in disease conditions) is
needed to convert flax to the anti-inflammatory form we need, and that
Flax also contains Omega 6, the clear winner is fish, with a
supplemental form being both convenient and pure.
The two fatty acids present in high
amounts in Fish Oil are EPA and DHA, both precursors to important
ANTI-inflammatory substances in the body, and both connected in studies
to a lowered risk of cancer.
Additionally, a 2003 study at the
University of Edinburgh determined that Omega 3s can halt and reverse
the weight loss and lack of appetite (Cachexia) experienced by some
cancer patients. See RESOURCES
at right for the study report.
This is why the recent no-fat fad
disturbed me so much: I was seeing an increasing number of young girls
coming for advice for premenstrual problems, hair, nail and skin
problems, and lack of energy . The message I try to
convey is that entirely excluding any essential part of the diet is
will not benefit us in the long run: what works is
BALANCE. Lean proteins, fresh
fruits and vegetables, moderate amounts of complex carbohydrates,
and moderate amounts of friendly sources of unsaturated fats - such
as olive oil, macadamia nut oil, walnut and flax oil,- fresh water
and the occasional indulgence: this is the diet our bodies were
designed for, and the one to keep us light and healthy!
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To reiterate: the S.A.D (Standard
American Diet) has long been notorious for being high in fat, so
where do I get the idea that anyone could possibly not be getting
enough fats?
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The secret lies in the word
"certain": certain fats, not all fats, are essential to
vibrant health. This is the case not only where fairly minor health
problems are concerned, but also in some serious conditions. One of
the interesting facts presented to us at a recent Convention, was
that a connection is now being made between lack of the necessary
fatty acids, and the present high cholesterol epidemic.
Dr. Siguel, one of the foremost international
experts on the subject of fatty acids, has hypothesized that LDLs (
Low Density Lipoproteins) in the body are actually part of the
transport system for EFAs (Essential Fatty Acids), and that when
insufficient supplies of these are available the LDLs are produced
in greater quantities in order to supply the cells with the EFAs
they need.
He feels that low levels of EFAs are one of the missing
links in relating nutrition to coronary heart disease, and suggests
that heart patients need to bring their EFA blood profile closer to
that of healthy people. An added benefit for heart health is that
while the Arachidonic acid obtained from animal fats is highly pro-aggregatory
(the Linoleic acid contained in such fats is a precursor only
for Arachidonic acid and subsequently inflammatory PGE2) the good
Omega 3 fatty acids such as Fish Liver Oils (FLO) produce PGE1
(Prostaglandin E1), a potent inhibitor of platelet aggregation.
Remember, fats are often replaced in fat-free
foods by carbohydrates, causing high insulin production in the
body which in turn shuts down the enzyme pathways through which
Arachidonic acid is converted to the friendly GLA. This in turn
means the messengers (eicosanoids) which promote insulin sensitivity
in the cells are not sent to do their jobs, more insulin is produced
to take care of the added carbs, and a vicious cycle leading
potentially to diabetes, cardiovascular problems and possibly even
cancer.Syndrome X, or
Insulin Resistance is set in motion.
Another option for lowering cholesterol and, some
studies suggest, blood pressure, is flax seed oil. High levels of
Fish Oil have even more dramatic affects, and in my opinion it is
essential to balance the Flax Oil's Omega 6 with Omega 3.
While some
are suggesting that Flax, or Soy or Walnut Oils can give the same
Omega 3 benefits as Fish Oil, the unfortunate fact is that the while
they do contain ALA (alpha- linolenic acid, the precursor to EPA and
DHA) individuals vary greatly in the extent to which the conversion
occurs in the body since many people lack the necessary
enzyme, delta 5 desaturase. Yet others are eating high levels of
carbohydrates and thereby inhibiting that enzyme.
One
estimate is that less than 1% is converted. ALAs role as an energy
source means also that most of it is removed from the blood stream
before conversion can take place. See RESOURCES at right for a
(very) comprehensive report by a true expert! It is even possible
that in people who are trying to correct a disease state, the
existing imbalances in the body may further compromise this
conversion.The only way to get a reliable supply of EPA and DHA,
in my opinion is through Fish Oil supplements.
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Your
Grandmother will have told you that fish is brain food, and
surprise!
She was right!
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An added plus of Fish Oil
is the DHA content, an upcoming star in sustaining brain function.
Gradually we are coming to recognize the
importance of DHA for mental function and vision, but new
research suggests it also plays a role in resistance to diabetes. An
omega-3 fatty acid found in fish oil appears to improve insulin
function in overweight individuals who are vulnerable to type 2
diabetes, researchers report. Three months of daily supplementation
with docosahexaenoic acid (DHA) produced a "clinically significant"
improvement in insulin sensitivity in overweight study participants,
according to Dr. Yvonne Denkins, a nutrition researcher at the
Pennington Biomedical Research Institute, Louisiana State University
in Baton Rouge. What is going on here is the cycle I describe
above.
Remember, also, that the importance of Omega 3s
increases during pregnancy, where the developing fetal brain and
vision competes with the mother's requirements for this nutrient.
There is some suggestion, in fact, that lower levels of Omega 3s in
the mother are a contributing factor in preeclampsia. Certainly,
it takes about 3 months after delivery for the mother to replenish
her supply of DHA. Its presence in breast milk takes first priority
and its importance for the infant can hardly be over-emphasized
throughout pregnancy. Sadly, levels of DHA in the milk of American
nursing mothers is falling dramatically.
PGE1 also affects the hormone prolactin, high
levels of which are implicated in many of the problems associated
with PMS (and prostate problems, incidentally): GLA (Gamma
Linoleic Acid) from Evening Primrose Oil has been shown in double
blind studies to reduce symptoms significantly, the most outstanding
results being with fibrocystic breast disease, where 45% of those
with cyclical symptoms improved on GLA: PGE1 actually blocks the
formation of Arachidonic acid and PGE2, levels of which are higher
in patients with these types of breast problems. It is interesting
to note that deficiencies of B6 interfere with the conversion of
Omega-3 fatty acids into EPA and DHA, and that birth control pills
increase requirements for B6. A complicated cycle!
Evening Primrose oil is not the only
excellent source of GLA: some actually argue that Borage Oil
is a better and less expensive source. Viewed purely objectively,
it seems to me that I have better results for menopausal problems
with EPO, but studies have shown Borage Oil to be medically
effective in Rheumatoid Arthritis, where it reduces the pain and
joint stiffness. A recent (HSR Mar 2000) study at the Shriner's
Hospital for Children found participants responding favourably to
treatment with Borage Oil. in Diabetic Neuropathy patients treated
with GLA experienced significant improvement in reflexes, muscle
strength and sensitivity to touch (among other parameters). Studies
on Borage Oil's use in cases of high cholesterol show an effective
dose to be in the 1 to 4 gram range, with improvement in LDL and HDL
levels being noted after 2 months. With cardiovascular disease,
doses of 4 to 5 grams were shown to reduce blood pressure, and
suggest that it may also inhibit some of the processes which lead to
plaque forming in blood vessels. A study published in the Journal
of Hypertension in 1996 showed that 1 gram of GLA taken for four
weeks lowered blood pressure during stress exposure tests , where a
placebo control group evidenced an increase in blood pressure.
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Fatty acid levels are also abnormal in conditions
such as eczema and psoriasis, food allergies, diabetes,
rheumatoid arthritis and Multiple Sclerosis.
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Interestingly,
results have also been seen with supplementation of EFAs for
Raynaud's syndrome and the dry eyes associated with Sjogren's
symptom . Much of this success is due to the anti-inflammatory
action of PGE1.
Recently, there has been interesting research
linking prostaglandins to hyperactivity in children. A
British organization called Hyperactive Children's Support Group has
witnessed some dramatic results in these children when supplementing
with EPO (Evening primrose Oil). The group has found some figures to
suggest that hyperactive children often have problems with alcohol
as they grow up, and alcoholics also appear to be deficient in GLA
and PGE1. Alcohol raises levels of PGE1 temporarily, and PGE1 has
recently been found to be one of the key determiners of moods. EPO
is therefore also being tested to see if it can play a role in the
prevention of alcoholism and provide protection against the damage
it causes. It seems to me a strong possibility that inadequate
intake of EFAs by the Mothers could definitely play a part in this:
I suggest that supplementation with Omega 3 fatty acids during
pregnancy might do a great deal to both increase mental development
in the fetus, and protect against not only neural problems, but
ADD/ADHD after birth.
Causes of EFA deficiency are mostly diet related:
low intake of GLA oil - high dietary levels of saturated or
mono-unsaturated fats - low levels of the nutrients B6, B3, C and
zinc, - moderate to high consumption of alcohol - but also diabetes
- and even the process of aging.
Certainly in my opinion enough evidence exists to
encourage us to make sure that we are getting enough of the proper
forms of this essential nutrient, even if we have to take
supplements to do it!
| Keywords: essential fatty acids
energy, essential fatty acids hormones, omega 3 flax, essential
fatty acids heart, essential fatty acids cholesterol, the
vitamin lady writes about essential fatty acids |
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