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By Radhia Gleis PhD, C.C.N.
Enjoy Whole Health Sept/Oct, 2004
For years we have been told that fats are the “bad guys”
of the diet story. Yet science tells us that there are good
oils--not just less-bad-for-you oils, but oils that positively
improve health in many unexpected ways. Trying to figure out
"who is who" in this story has been difficult for
the public; over the years, scientists change their views
regularly.
Polyunsaturated oils such as safflower and sunflower apparently
were the “good guys” in the fat realm for some
time, only to be discredited later as possibly leading to
cancer. More recently, olive oil has been the favorite, but
the oil story is not that simple.
To appreciate the specific roles that different fats or
AKA fatty acids have on health, it is first useful to understand
their basic chemical structure. Fatty acids are long chains
of carbon atoms bonded to each other by hydrogen atoms. The
fatty acid molecules are grouped as saturated or unsaturated.
A saturated fatty acid has one hydrogenated bond between
each pair of carbon atoms in the chain. It is literally “saturated”
with hydrogen atoms. These hydrogen bonds hold the molecule
stable. Saturated fatty acids come from animal sources, such
as meat, dairy, butter, and lard as well as coconut and palm
oil and stay solid at room temperature.
An unsaturated fatty acid has two bonds, called double bonds,
between some of its carbon-atom pairs. This double bond takes
the place of the hydrogen bond. Unsaturated fatty acids can
be further divided into two groups: monounsaturated and polyunsaturated
fatty acids.
“Mono”, means one therefore, monounsaturated
fatty acids have a double bond between only one carbon-atom
pair, making them a flexible molecule such as oil, which doesn’t
stay solid at room temperature. They are found mainly in plant
foods, such as olive, canola, and peanut oils. Monounsaturated
fats are the best choice because they lower LDL cholesterol
without lowering HDL “good” cholesterol.
“Poly” means many, so polyunsaturated fatty
acids have a double bond between more than one carbon-atom
pair, making them a very flexible molecule. Some polyunsturated
fats such as flax seed oil don’t even stay solid in
the freezer. Polyunsaturated fat, found in sunflower, corn,
soybean, and safflower oils, as well as in some fish, has
been linked to decreasing total blood cholesterol by lowering
LDL.
Omega-3 fatty acids, which may help lower the risk of heart
attacks, are highly polyunsaturated and are found mostly in
seafood. Omega-6 fatty acids are also polyunsaturated, and
they function to protect the body's cells. Sources of omega-6
fatty acids include whole grains, vegetable oils, seeds, and
nuts.
There are three elements that can break these delicate unsaturated
oil molecules: heat, light and oxygen. The more unsaturated
the molecule the less stable and vulnerable to breaking these
molecular bonds. This will cause these oils to become rancid
and produce toxins and free radicals that can be detrimental
to good health causing inflammatory and degenerative disease.
A word of caution: Omega-3-rich oils are highly polyunsaturated.
This means that unless they are very, very fresh, they--like
other polyunsaturates (safflower and sunflower oils, for example)--may
deteriorate in such a way as to cause harmful effects in our
bodies. The bottom line: refrigerate and consume within a
few weeks any flax seed oil or seeds. Buy walnuts still in
the shell, and preferably vacuum-packed for freshness.
It is partly because of the freshness issue that monounsaturated
oils, such as olive, have become so popular. Their chemical
structure is such that they remain stable--that is, they do
not oxidize--as readily as do polyunsaturates. As with other
mono-unsaturates, intake of olive oil reduces levels of the
harmful form of cholesterol in the blood compared to more
saturated oils.
When cooking with fats and oils it is important to do so
in a manner that does not destroy them. Never consume any
deep fried foods; they are all universally soaked with toxic
isomers. Remember that if the oil starts to smoke it is too
hot and it is being destroyed. Here is a list of cooking oils
and a brief comment on them.
Olive Oil: Contains many mono-unsaturated fatty acids. It
is good for pan frying but not good for deep frying. It will
break-down and become rancid. Be sure to mix some water with
it to prevent the oil from getting too hot.
Coconut Fat: Good for frying only if it is not hydrogenated.
Frying with hydrogenated fats are extremely dangerous to your
health. In addition to the trans-fatty acids of hydrogenated
oils, they contain traces of metallic nickel which is used
in the process of hydrogenation.
Clarified Butter (Ghee): Very good for frying. Commercial
users with find it to be more expensive that other oils.
Peanut Oil: Recommended for home or commercial use. You
can use the same oil every day but it should not be used more
than a few hours each day. It is suggested that you use only
organic peanut oil as oil processed from moldy peanuts can
be contaminated with aflotoxins, a known carcinogenic byproduct
of the mold fungi.
Sunflower Oil: You can fry with this oil all day, but you
cannot safely cool and re-use the oil. It needs to be disposed
of at the end of the day.
Macadamia Nut Oil: A great new healthy alternative cooking
oil is called MacNut™ oil. One of the great features
of this oil is that it is low in saturated fats plus it has
the ideal 1:1 ratio of omega 3 to omega 6 fatty acids. In
addition, it has a smoke point of 410ºF which makes it
well suited for stir frying foods.
Canola Oil: Made from genetically engineered rapeseed and
used extensively in restaurants. Registered with the EPA as
an insecticide. There is much controversy surrounding this
oil. From the research I've read related to this oil, I would
suggest avoiding it Refined Vegetable Oil: Totally devoid
of nutrients and breaks down easily. Should be totally avoided.
Even as a salad oil.
As long as polyunsaturated fats are left in their natural
state, known as the cis form fatty acid, they are healthful,
but when vegetable oils are removed from vegetables, they
turn rancid rather quickly. So manufacturers use a chemical
process that converts healthful polyunsaturated oils into
cancer and heart attack-causing partially hydrogenated fats,
also known as trans fatty acids.
For the most part fats that have undergone chemical alterations are
referred to as "hydrogenated," "partially
hydrogenated" and even "polyunsaturated." This
process simply bubbles hydrogen gas through warm oils which
were chemically and physically extracted from vegetable sources
such as soybeans. The hydrogen bonds to the fat molecules
so that oxygen can no longer interact with it. During hydrogenation,
the oil changes from a clear liquid to a solid at room temperature.
When fats are hydrogenated something drastic happens to
their vital and life-sustaining characteristics. Hydrogenation
destroys the nutritive value of the fat and creates a slow-developing
toxicity demonstrated to be involved in (if not totally responsible
for) diverse diseases including heart diseases and cancer,
the two leading causes of death.
These “pseudo fats” are also referred to as
"polyunsaturated." If that word sounds familiar
it is. It's the same word repeated millions of times in TV
commercials designed to dupe you into believing that hydrogenated
fats are really healthy. Nothing could be farther from the
truth.
Fat has many duties in our bodies. In order to maximize
good health, we need avoid all refined and hydrogenated fats
and eat healthy mono and polyunsaturated fats. For more information
on your health and dietary needs please contact
our office.
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