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By Chris D'Cruz
Consider the following characteristics which apply to all foods :
All natural foods
contain some substances which are essential to life. Oils for example, found
in nuts and seeds, contain Essential Fatty Acids (EFAs) in amounts which
are significantly greater than in other foods. Fresh oils also usually
contain the fat-soluble vitamins A and E.
Typical EFA profile for Hemp Seed Oil
Alpha Linolenic
Acid (Omega 3) (LNA ) 25 %
Linoleic Acid
(Omega 6) (LA) 53 %
Gamma Linolenic
Acid (GLA )
1.9% -> 5 %
There are several
factors that affect the amount of EFA's which end up in the oils we consume.
These include the species of seed used, where it is grown, genetic
manipulation of the seed and the oil-production method.
Plant breeders have
developed high Oleic varieties of seeds, which do not contain significant
amounts of EFA's but do contain a high proportion of oleic acid, the mono-unsaturated fatty acid found in olive oil. Oils pressed from such seeds are
not so easily damaged during processing but they do not contain the
Essential Fatty Acids required for human health.
The fats that we
require are different from the kinds available in Supermarkets and Health
Food Stores. Modern oil extraction causes much damage to delicate EFAs.
Most of the vegetable
oils/margarines on sale are labeled to show amounts of saturated,
mono-unsaturated and poly-unsaturated fatty acids (sometimes called
"Essential poly-unsaturates" or PUFAs) contained. Unfortunately these oils
are extracted using high temperatures and pressures. This significantly
darkens the oil and causes it to take on an odour. The oil is then bleached,
deodorised and de-gummed chemically to "clean" it up. It may then also be
partially hydrogenated in order to "stabilise" it, i.e. to prevent it from
going rancid. Partial hydrogenation and trans fats (which are produced
during this processing) have received bad health publicity in recent years.
It is true that the
fatty acids chains of hydrogen and carbon atoms, in these industrially
extracted oils, may have the same chemical formulae as in the original seed
but the spatial arrangement of the atoms has been altered. In nature, the
unstable cis form predominates whereas in processed oils the trans form is
present in increased proportion.
Enzymes in our bodies
which metabolic these fats recognise only the cis form. It must be the case
that, without Essential Fatty Acids in an undamaged form, these enzymes will
be unable to do their job.
Industrially
processed oils do not go rancid rapidly because their compositions have been
altered. The fragile but essential components have gone.
EFA's are unstable
and turn the oil rancid if care is not taken. Since EFAs are spoiled by
exposure to light, heat and air, products should be carefully produced to
minimize the damage caused by these agents. Products should be packaged and
shipped to you with the minimum of delay from the time of pressing.
N.B. : Although flax
seed oil contains more Alpha Linolenic Acid (Omega 3) than does
Hemp Seed Oil, Hemp Seed Oil is considered as a better balanced oil for general
consumption. Also, because of the natural anti-oxidants found in Hemp, the
oil remains fresh for longer.
If you wish to learn more about the role of Essential Fatty Acids in health,
the following books may be a start:
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