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The Real Story on Canola Oil
(Can-ugly Oil)
The Hampton’s Diet Fred Pescatore, MD, MPH, CCN
The Science of Fats, Fatty Acids and Edible Oils
Choosing the Right Oils and Fats
Can-ugly Oil my pet name for canola oil. Since canola is a
completely contrived substance, I thought it should have an equally
ridiculous name. The patient who first turned me off of canola oil
lost 58 pounds following the Hamptons diet. Trevor was thrilled to
finally discover a diet that emphasized high levels of
monounsaturated fats, good saturated fats and downplayed the
seemingly glorified horror that is canola oil. He is a 67 year old
man who worked for a major pharmaceutical company for his entire
career as a chemist. He understands the chemistry of the fats much
more intimately than I do; still, we came to the same conclusion. He
wanted to lose weight but was having difficulty following a low
carbohydrate diet approach that did not emphasize the good, healthy
fats. Trevor had a heart attack four months prior to seeing me and he
did not want to take any cholesterol lowering medications and was
looking for a way to avoid that, if possible. He was so relieved on
discovering my approach that he even helped me out with some of the
chemistry you see in this book. He was a model patient and lost his
weight in 6 months. His cholesterol dropped to the 170’s with his HDL
level staying in the low 70’s and triglycerides in the 40’s. I will
try to relate to you what he told me about the rape seed.
Can-ugly oil is derived from the rape seed which is a member
of the mustard family, which also includes broccoli, kale, cabbage
and mustard greens. Rape seed oil has been used in traditional Asian
and South Asian cooking for many years, without cause for alarm. This
is probably because the oil was processed at very low temperatures
usually by hand. A study raised concerns about heart disease and its
relationship to one of the fatty acids that was most prevalent in
rape seed oil, erucic acid. Since that was determined, the rape seed
that is used today to make canola oil was bred to eliminate virtually
all of the erucic acid so that now instead of 45% erucic acid that
you get from a traditional rape seed, there is generally less than
25% found in common canola oil.
Canola oil is named for a
Canadian scientist who developed it, hence, Canadian oil or canola.
This new rape seed was bred to have a fatty acid profile of 57%
monounsaturated fat; 5% saturated fat; 24% omega-6 fat and 10%
omega-3 fatty acids. Because there is a decent level of omega-3
fatty acids, it is not recommended that canola oil be heated above
120F or trans fats are formed. Considering the profile, canola oil
looks like a decent product. However, there are some canola oils
whose smoke point is 520 F – how did that happen? That is all from
chemical manipulation of the chemical structure of the oil through
refinement and processing. So, although there is a 2:1 ratio of
omega-6 to omega-3 fatty acids, unless canola oil is used cold, and
even then there is controversy, it is of little use and the levels of
trans fats are extremely high at 4.5%, more so than margarine.
Traditionally rape seed oil was probably okay due to its
gentle processing technique. However, modern canola oil processing
is far from gentle and is what is responsible for making it can-ugly.
The oil is removed from the seed by a combination of high temperature
mechanical pressing and solvent extraction. As you will recall,
traces of the solvent usually remains in the oil. Then, the oil is
further refined, bleached and degummed, each step requiring exposure
to high temperatures and chemicals. Since canola oil has a large
amount of omega-3 fatty acids, these easily become rancid and foul
smelling during these high heat processes. It therefore has to
undergo another refining process called deodorization. This
deodorization process removes a large portion of the omega-3 fatty
acids by turning them into trans fats – which can be as high as 4.5%.
Now, canola oil is one of the most commonly used oils in
processed foods. Since this oil has already been damaged by its
refining process, it then undergoes another process that I have
already described called hydrogenation, which further increases the
trans fatty acid content of a given food. Canola oil is preferred in
the processed food industry not only because it is cheap but because
it hydrogenates better than soy or corn oil – an important component
for shelf life stability, but not human health.
Canola Oil Mythology
In order to understand how canola oil came from not even
existing on the planet to being one of the most commonly consumed
oils in the American diet, we really don’t have to go back too far –
only to the 1980’s. At that time, polyunsaturated fats ruled the
roost and were the oils that were promoted as heart healthy. Science,
however, was beginning to understand that the polyunsaturated stand
was unhealthy. The powers that be could also not go back to a
position that saturated fats were healthy again after they spent the
better part of a decade or longer telling us that the thought of them
would kill us. This was the birth of the reign of the monounsaturated
fats. But, like most things governmental, the message got misguided
and distorted by the food processing industry to give us what they
can make the most money on. It is only now with the birth of the
reign of MacNut oil and the success of the Hamptons diet can
monounsaturated fats finally find a good home and be the bearer of the health message that they should.
In the mid-1980’s, articles on the benefits of olive oil, a natural monounsaturated fat, began to appear in the press. Consumers latched onto this as it seemed natural and the images of the Mediterranean and Tuscany seemed fitting for a healthy lifestyle. However, because of its expense, there had to be a cheaper alternative to use in processed foods; and, because of its relative scarcity, there needed to be an alternative. Another thing to note is that olives do not grow that well in the US as there are not that many areas of the country that have a Mediterranean-type climate. But, rape seeds are perfectly suited to growing in the US and thus became the darling of the USDA. So, that’s when a Canadian scientist developed a rape seed that was high in oleic acid and low in erucic acid, the poisonous substance – hence, the birth of LEAR (low erucic acid rape seed) or what is now known as canola oil.
This term canola oil did not come into widespread use until the
1990’s; although it was coined earlier than this. Since canola oil
was a food product that was totally new; and the marketers wished to
get it into the marketplace right away, it needed to be granted GRAS
(generally recognized as safe) status. Otherwise, it would not be
allowed into the United States food supply, nor sold as food or used
in the food processing industry. Without research and testing on the
product, which is normally required fro many years, this as yet
untested food product was granted GRAS status by the USDA in 1985.
It is interesting to note that Stevia, a non-caloric safe and
natural sweetener with no friends in the food processing industry was
never granted this same status although it is not a new, man-made
contrived substance, nor is it a new food product, having been used
for many years without any reported problems by many other countries
besides the United States. Unfortunately, Stevia is only allowed to
be sold as a nutritional supplement and not as a food. The interest
of big business is always at stake, even in our food supply.
Thus, the marketing of canola oil as a health food began in
earnest. The marketing genius drew on the fact that canola oil had
10% omega-3 fatty acids – which at that time was brand new to
consumers. Canola oil began to be used interchangeably with olive oil,
as the lighter alternative with the same healthy characteristics –
something that could not have been further from the truth.
Unprocessed canola oil which can not be found in our food supply
does contain high levels of both monounsaturated fats and omega-3
fatty acids, but not the processed variety, the most common one.
That is because a product with that much omega-3 fatty acids is not
shelf stable. This marketing campaign was very successful and helped
push this crop into one of the most widely planted in the world today.
It is even the oil most commonly used in cholesterol lowering spreads
in place of traditional margarines – a big mistake; and canola oil is
the oil of choice in most restaurants.
The Dangers of Can-ugly
Oil
There have been many warnings in the health food industry
that canola oil is unhealthy and the average health food consumer
understands the limitations of this oil. It is interesting to note
that canola oil started its meteoric rise in popularity in the health
food markets and now is shunned by the healthiest consumers. Several
studies in animals have shown that canola oil can decrease the
bio-availability of vitamin E, a critical component of cardiovascular
health.
Also, canola oil consumption can lead to shortened life spans
in other animals. In still another study, growth is retarded and
hence the ban on the use of canola oil in infant formulas. If this
was so safe, why can’t it be fed to human infants? Keep in mind that
these studies were all done on animals and it is hard to make that
leap into humans. The one thing that is known is that there have
never been long term studies in humans as to the health benefits or
to the dangers of canola oil – another uncontrolled experiment that
only benefits one thing – the food processing industry. That is
something to seriously consider when deciding which oil to reach for
on the supermarket shelf.
I can’t help but wonder if canola
oil in and of itself isn’t responsible for the dramatic rise in
obesity and diabetes that we have experienced since it became
fashionable. I guess it is something we will never know.
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