We have all been hearing a lot lately about our Omega-3
fatty acid to Omega-6 ratios and how the typical western
diet has "flipped" the ratio backwards. Basically, we eat
too many omega-6, not enough omega-3 and too much saturated
and trans fat. Omega-3 fatty acids are sorely lacking in
the typical western diet having been replaced by oils with
a high proportion of omega-6 oils such as corn oil.
So what does all this mean?
The fats in foods are a combination of saturated,
monounsaturated and polyunsaturated. Omega-3 and 6 fats
are polyunsaturated. All oils and fats contain combination
of the above. But, some fats have a higher proportion of
saturates (butter) or monounsaturates (olive oil) or
polyunsaturates (nut oils, corn oil, etc.).
Trans fats are produced when an oil is "hydrogenated".
More simply, the oils are processed to make them more
stable and less likely to go rancid quickly. Trans fats
are used in most processed foods and are not good for the
body. Vegetable shortening is hydrogenated oil - lots of
trans fats!
With the exception of trans fats, the body requires all of
the above fatty acids in different combinations. Yes - even
saturated fats. These fatty acids are used to help the
body absorb vitamins such as Vitamin A as well as a host of
processes like cellular metabolism and the manufacture of
hormone like substances. Alpha-linolenic acid is one of
two fatty acids traditionally classified as "essential."
The other fatty acid traditionally known as "essential" is
an omega 6 fat called linoleic acid. "Essential" means that
the body is unable to manufacture them on its own and must
come from the diet.
The body converts alpha-linolenic acid into two important
omega 3 fats, eicosapentaenoic acid (EPA) and
docosahexanoic acid (DHA). EPA plays a role in the
prevention of cardiovascular disease, while DHA is the
necessary for proper brain and nerve development.
Omega 3 fats also play a role in the production of
hormone-like substances called prostaglandins.
Prostaglandins help regulate many functions like blood
pressure, blood clotting, nerve transmission, inflammation,
allergic responses, kidney function, gastrointestinal
function and the production of other hormones.
Depending on the type of fat in the diet, certain types of
prostaglandins may be produced in large quantities, while
others may not be produced at all. This can lead to an
imbalance in the body and ....disease.
From omega-3 fats are manufactured series 3 prostaglandins,
which act to reduce platelet aggregation, reduce
inflammation and improve blood flow. From omega 6 fats are
manufactured series 1 and series 2 prostaglandins. Like
series 3 prostaglandins, series 1 prostaglandins are
beneficial. On the other hand, series 2 prostaglandins
promote inflammation and increase platelet aggregation.
This is why it is important to balance the amounts of omega
3 and omega 6 fats in the diet- aiming for a higher
proportion of omega-3 fats.
Polyunsaturated oils are extremely susceptible to damage
from heat, light, and oxygen. When exposed to these
elements for too long, the fatty acids in the oil become
oxidized. The oil becomes rancid which means it tastes and
smells different. Oxidation also means free radicals. Free
radicals are not a good thing - contributing to the
development of degenerative diseases and cancer. Hence,
polyunsaturated oils should be stored in dark glass,
tightly closed containers in a cool place. Also, cooking
with oils high in polyunsaturates produces free radicals. A
better choice for cooking are oils rich in monounsaturates
(such as olive oil) which do not change in composition as
much when heated. Saturated fats (like butter) also do not
oxidize much when cooking, but only should be used in
limited amounts.
If you want to increase your omega-3 intake, the foods
providing the best omega-3 profiles are flaxseeds, walnuts
and salmon. There are many other foods rich in omega-3
fats as well as the oils derived from these foods. A simple
web search for "foods rich in omega-3 fats" will give you
all kinds of information on this topic.
To your health!
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About the Author:
Ainsley Laing, MSc. has been a Fitness Trainer for 27 years
and writes exclusively Body for Mind eZine. She holds
certifications in Group Exercise, Sports Nutrition and
Personal Fitness Training. She is also a professional
engineer and mom. To see more articles by Ainsley visit
http://www.bodyformind.com or the blog at
http://www.bodyformind.blogspot.com
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