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In
the course of evolution, human beings lost the ability to make enzymes
that produce the omega-3 and omega-6 fatty acids. These fatty acids are
essential to life and must therefore be supplied by the diet as they
cannot be synthesised by the body, hence the term essential fatty acids
(EFA).
A
balance existed between omega 6 and omega 3 for millions of years during
the long evolutionary history of man, and genetic changes occurred
partly in response to these dietary influences. However, rapid dietary
changes over short periods of time as have occurred over the past 100-
150 years is a totally new phenomenon in human evolution.
Some
indications that an EFA deficiency or imbalance are present are: dry
skin; the need to use moisturizing creams and lotions; "chicken
skin", the presence of tiny rough bumps, usually on the back of the
arms; dry or unruly hair; dandruff; soft, fraying or brittle nails;
menstrual cramps; premenstrual breast tenderness.
EFAs support cells
by:
·
Keeping
membranes fluid and flexible
·
Holding
proteins in the cell membrane, easing the traffic of nutrients and
promoting normal detoxification
·
Contributing
to structural parts of the cell (endoplasmic reticulum, the Golgi
apparatus, the vesicles, the mitochondria, the nucleolus and the
nucleus)
·
Facilitating
electrical channels on the membrane, allowing bioelectrical messages to
pass from cell to cell (important in neural transmission)
Omega-3
Fatty Acids
Omega-3
fatty acids fall into two major categories: plant derived, yielding
alpha-linolenic acid or marine derived (fish oil, yielding both EPA and
DHA).
The
omega-3 fatty acids can be supplied as alpha-linolenic
acids (ALA) (from green leafy vegetables,
canola [rapeseed], flaxseed
[linseed] oils, soybean, walnut, and Brazil nuts),
Eicosapentaenoic
Acid (EPA)
(seafood) and
Docosahexaenoic
Acid (DHA)
(available from tuna, tuna/salmon oil, organ meats: brain, liver, DHA
enriched foods).
Deficiency
Signs
·
Growth
retardation
·
Weakness
·
Impairment
of vision and learning ability
·
Motor
incoordination
·
Tingling
sensations in arms and legs
·
Behavioural
changes
The
human brain is rich in omega-three EFAs (comprising approximately 60% of
the weight of the brain); their deficiency causes abnormalities in the
development and function of the nervous system as well as immune
defects.
DHA
in retina and postsynaptic membranes is crucial for adequate functioning
of embedded proteins, i.e., rhodopsin for vision and postsynaptic
receptors for neurotransmission.
Research
on Omega-3
Omega-Research
is a website with comprehensive studies available to access on-line
which show the valuable benefits of supplementing omega-3 oils to
children and adults.
Flaxseed
Oil or Fish Oil?
Extensive
research published since 1985 has demonstrated that flaxseed
oil can prevent
cancer, improve bone health, birth defects in animals.
Fish
oils, the other
concentrated source of omega-three's, have made front page news because
of their ability to prevent disorders such as cancer, heart attacks, migraine headaches, and premature
births, and to reverse the effects of conditions such as psoriasis, ulcerative colitis, rheumatoid arthritis and cystic fibrosis.
More recently the
benefits of omega-3 oils in the treatment of children with behavioural
disorders is finally being accepted by the medical profession and being
reported more widely in the news.
Many
parents supplement flaxseed oil to their children instead of fish oils
in the belief that the body will convert to EPA and DHA (see
Essential Fatty
Acids diagram).
However,
conversion
of ALA to DHA is either limited or absent in adults. In
a trial where participants were given 3g of a-
Linolenic acid from flaxseed oil, plasma EPA
levels at 12 weeks in the flaxseed oil group
increased by 60%,
and docosapentaenoic acid
(DPA) levels increased by 25%.
Plasma DHA
levels did not change. Even so
the conversion of alpha-lenolenic acid (ALA) to EPA depends on the
efficiency of the enzyme
delta-6-desaturase, can
be inhibited by various conditions such as a diet high in linoleic acid
(Omega-6), trans-fatty acids such as fast foods and baked goods, alcohol
intake, certain health conditions, and the
lack of
co-factors, including
vitamin
B6, B3, vitamin C, magnesium and
zinc.
Also there is competition between omega-3 and omega-6 for the
delta-6-desaturase enzyme.
For
the sake of balance regarding the conversion of ALA to EPA and DHA
there is counter argument put forward by Dr
Udo Erasmus, author of the book "Fats That Heal Fats That
Kill". What would happen if a person could not convert ALA to EPA
and DHA? They would be dead! Therefore the studies that there is no
or minimal conversion of ALA to DHA are misleading.
Conversion
of ALA to DHA and EPA is decreased by
low vitamin B6, B3, C, magnesium, zinc, and being male (females convert
more effectively due to oestrogen). If DHA is low it lasts longer in the
body and conversion in the brain is 2-6 times faster than in other
tissues. Studies that measure peripheral levels of EPA and DHA are not
reflective of tissue levels, especially brain levels.
Fish
oils are highly processed
to ensure purity from contaminants (heavy metals, dioxins and PCBs) and
to ensure a pleasant taste to increase patient compliance. However this
increases processing
damage molecules
(molecules damaged by processing). Manufacturers don't talk about
processing damage, the focus is only on industrial toxin levels. No
manufacturer lists levels of the following processing damage molecules
in their product specifications:
No
studies have been undertaken to examine the possible adverse effects of
these molecules. It
is interesting to note that studies using fish oils published pre-2003 show better
results than studies published post-2003 with more highly refined /
deodorised oils.
For
an excellent review
by Dr Udo Erasmus, click
here.
So
the question remains, seed oils or fish oils?
In
my clinic I use both depending on need. Fish oils especially cod liver
oil (Nordic Naturals Arctic Cod Liver Oil) if there is a requirement for
additional vitamin A and/or vitamin D. A blend of seed oils with a
balance of omega-3, 6 and 9 essential fatty acids if high levels of
vitamin A and D are not required or if fish oil compliance is an issue.
Udo
has been researching essential fatty acids for over 25 years and has
developed a pure, cold extracted blend of oils (Udo's Ultimate Oil
Blend), and if additional DHA is required (expectant mothers or young
children) then an oil blend is now available with DHA extracted from
algae (Udo's DHA Blend). Care if there is a sensitivity to soy as this
oil blend contains lecithin which is soy based.
Omega-6
Fatty Acids
Although
most people consume more than enough of the omega-6 EFAs, there
is a small but significant proportion of the population (about fifteen
per cent, who are unable
to properly metabolize omega-6 EFAs and will benefit from
supplementation with oils that are rich in omega-6's.
Deficiency
Signs
·
Skin
problems (itching, eczema, dry patches)
·
Hair that is
thin and weak
·
Nails that
crack and break
·
Behavioural
changes
The three most
useful omega-six rich oils are
evening primrose oil, borage oil
and
black currant seed oil. These
oils contain gamma-linolenic acid
(GLA), which
allows the body to produce compounds called prostaglandins which help
control inflammation, dilate blood vessels, promote healing and regulate
water loss.
In
some conditions such as kryptopyrrole
disorder there is a requirement for more omega-6 rather than omega-3.
Interactions
and Precautions
Unfortunately
we cannot inter-convert Omega 3 and Omega 6 fatty acids within our
bodies, so it is essential to eat the right proportions. When we get
this ratio too far out of balance, problems can develop:
·
Excessive levels of Omega- 3 may reduce blood
clotting time.
·
Excessive levels of Omega- 6 increases the risk
of coronary heart disease.
Essential
Fatty Acids and Autism
Listed
below are a number of studies that have looked at the deficiencies of,
and benefits of essential fatty acids in autism.
Omega-3
Fatty Acids Supplementation in Children with Autism: A Double-blind
Randomized, Placebo-controlled Pilot Study.
Essential
fatty acids and phospholipase A2 in autistic spectrum disorders.
Plasma
fatty acid levels in autistic children.
Fatty
acid metabolism in neurodevelopmental disorder: a new perspective on
associations between attention-deficit/hyperactivity disorder, dyslexia,
dyspraxia and the autistic spectrum.
Clinical
trials of fatty acid treatment in ADHD, dyslexia, dyspraxia and the
autistic spectrum.
For advice or to book a
consultation for your child call (03) 8802 7687 or email
me
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