As it was
underlined in the previous post, the olive oil
is the basic constituent of the Cretan diet. A
diet that is highlighted by the long live of
the cretan people and their good health.
Although these to two facts seem to be somewhat
unrelated, since one is a fat and the other is
health, the truth is (and it is backed up by
scientific evidence) that they shed some light
to the “mystery”. We will see why olive oil is
so good for you, but we will also see that
olive oil from olive oil is very different, not
only by the name they go by, but for the health
benefits.
Before we continue, let’s see first what an oil molecule is and how it is made. The foundation of all oils are the fatty acids. Fatty acids, and as all organic molecule consists of primarily Carbon and Hydrogen atoms.They are long chains of hydrocarbons terminating in a -COOH which is just an acid. One is shown in the picture below (a). To simplify the image we will do some assumptions that all chemist do (b). Carbon atoms are not shown but they will be assumed to be in either side of each line. The line will represents the bonds between the two items. The hydrogens are omitted because they don ‘t have any importance and they complicate the pictorial, but you can imagine that there are two in each carbon atom.
Before we continue, let’s see first what an oil molecule is and how it is made. The foundation of all oils are the fatty acids. Fatty acids, and as all organic molecule consists of primarily Carbon and Hydrogen atoms.They are long chains of hydrocarbons terminating in a -COOH which is just an acid. One is shown in the picture below (a). To simplify the image we will do some assumptions that all chemist do (b). Carbon atoms are not shown but they will be assumed to be in either side of each line. The line will represents the bonds between the two items. The hydrogens are omitted because they don ‘t have any importance and they complicate the pictorial, but you can imagine that there are two in each carbon atom.
The major
elements here are the length of the chains and
the bond type. The first item basically
determines the size of the molecule. The second
item is more important and determines the shape
of the molecule. Occasionally there is a double
bond meaning that one carbon atom is attached
to the next one with two bonds. That means not
only two less hydrogens, but also that creates
a kink in the molecule bending it as shown in
the picture. This is called monounsaturated
fat. If there are more than one double bond are
polyunsaturated.
This changes many
things in the properties of the molecule. As
you can imagine straight molecules can be
packed much more efficiently compared to the
kinked molecules. More packed molecules are
closer together making the macroscopic
properties more like a solid even at slightly
elevated temperatures. The kinked molecule on
the other hand are packed less cohesively
making them more like liquid rather than solid
in a wide range of temperature. Some studies
have shown that these kinds of fats can
actually lower LDL (bad) cholesterol and
maintain HDL (good) cholesterol. One drawback
with unsaturated fats, is that the double bond
is very easily broken and there are atoms that
can take its place. This results in rancidity
of the fats, and that’s why the food industry
does not prefer them over the saturated. One
more notable effect, is the effect they have on
cell membranes. Lipids like these, can come and
be adsorbed on the cell membrane
interstitially. Due to the high volume they
occupy they are pushing apart the bi-lipids
that consist the membrane making them more
elastic. This is especially good for the
arteries since the elasticity reduces the risk
of heart disease. It is theorized that, in the
long term, increased elasticity of arterial
walls reduces vascular stress and
consequentially the risk of two common causes
of death—heart attacks and stroke.
Since we are on
the topic we should mention about the omega-3
fatty acids that are monosaturated fatty acids,
with the double bond at a very specific
location. Omega denotes the endo of the chain,
while the 3 denotes the location of the bond.
So omega-3 means third from the end as in the
picture below. These include an “essential”
fatty acid, which means it’s critical for our
health but cannot be manufactured by our
bodies. Good sources of omega-3 fatty acids
include cold-water fish, flax seed, soy, and
walnuts. These fatty acids may reduce the risk
of coronary heart disease and also boost our
immune systems. Similar is the concept for the
omega-6 and omega-9 fatty acids, that are
however not so good for the heart.
And type fro
the big truth, the actual fats do not look like
that. Yes… I kinda lied. Well these molecules
are fatty acids, and they are the fats, but
they are nasty tasting and very foul smelling.
These are not what we eat. As I said these are
the building blocks that fats are made of. One
fat is actually made from a triglyceride which
is a glycerol molecule with three fatty acids
attached to it. The fundamentals of the
properties, we discussed above, are still in
effect and the significance of the double bond
is the same. A molecule that consists of oleic
acids, the major fatty acid of the olive oil,
LOOK LIKE THIS
And ow you know
why I did not drew this since the beginning.
Evidence from epidemiological studies suggests
that a higher proportion of monounsaturated
fats in the diet is linked with a reduction in
the risk of coronary heart disease. Although
the link is not yet understood it is something
that has been confirmed numerous times with
several unsaturated oils, predominately
however, with olive oil. This is significant
because olive oil is considerably rich in
monounsaturated fats, most notably oleic acid.
the Cretan diet has achieved this benefit, by
using olive oil to replace a similar amount of
saturated fat like butter, and animal rendered
fat. There is a large body of clinical data to
show that consumption of olive oil can provide
heart health benefits such as favorable effects
on cholesterol regulation and LDL cholesterol
oxidation, and that it exerts antiinflamatory,
antithrombotic, antihypertensive as well as
vasodilatory effects both in animals and in
humans. As they are the least processed forms
of olive oil, extra virgin or virgin olive oil
have more monounsaturated fatty acids than
other olive oil. These types also contain more
polyphenols, which may have benefits for the
heart.
Some clinical evidence suggests that it is olive oil’s phenolic content, rather than its fatty acid profile, that is responsible for at least some of its cardioprotective benefits. For example, a clinical trial published in 2005 compared the effects of different types of olive oil on arterial elasticity. Test subjects were given a serving of 60 g of white bread and 40 ml of olive oil each morning for two consecutive days. he study was conducted in two stages. During the first stage, the subjects received polyphenol-rich oil (extra virgin oil contains the highest amount of polyphenol antioxidants). During the second phase, they received oil with only one fifth the phenolic content. It was discovered that after the subjects had consumed olive oil high in polyphenol antioxidants, they exhibited increased arterial elasticity, while after the consumption of olive oil containing fewer polyphenols, they displayed no significant change in arterial elasticity.
To conclude I will refer to the observation that was made by the Rockafeler institute. In 1947 members of the Rockefeller Institute came to Crete in order to assess the health of the population after the war. They concluded that the level of their physical health was very good indeed. Cretans were 90% healthier than the American population. Even though the medical world needed a long time to comprehend the consequences of these discoveries, the basics of the Cretan diet have become a question for debate. Ten years later a study of seven countries, devised and directed by Dr. Ansel Keys, special cardiologist from Minnesota State, made Crete famous. He studied the health of people from 7 different countries; Holland, Finland, Japan, USA and of Mediterranean countries Italy, Yugoslavia and Greece. From Greece he studied Cretans and inhabitants of Corfu. From all the population groups studied, the groups of Italy and Yugoslavia presented lower mortality from cardiovascular diseases compared with the groups of North Europe and USA. However what astonished them were the results of Cretans; they presented the lowest rate of mortality, independently from the cause of death. The Research was continued in 1991. The Sector of Social Medicine of the University of Crete undertook the review of individuals that had taken part in the research 31 years previously, and found that the survival rate of the Cretan group was 50%, while in Finland there were no survivors.
Some clinical evidence suggests that it is olive oil’s phenolic content, rather than its fatty acid profile, that is responsible for at least some of its cardioprotective benefits. For example, a clinical trial published in 2005 compared the effects of different types of olive oil on arterial elasticity. Test subjects were given a serving of 60 g of white bread and 40 ml of olive oil each morning for two consecutive days. he study was conducted in two stages. During the first stage, the subjects received polyphenol-rich oil (extra virgin oil contains the highest amount of polyphenol antioxidants). During the second phase, they received oil with only one fifth the phenolic content. It was discovered that after the subjects had consumed olive oil high in polyphenol antioxidants, they exhibited increased arterial elasticity, while after the consumption of olive oil containing fewer polyphenols, they displayed no significant change in arterial elasticity.
To conclude I will refer to the observation that was made by the Rockafeler institute. In 1947 members of the Rockefeller Institute came to Crete in order to assess the health of the population after the war. They concluded that the level of their physical health was very good indeed. Cretans were 90% healthier than the American population. Even though the medical world needed a long time to comprehend the consequences of these discoveries, the basics of the Cretan diet have become a question for debate. Ten years later a study of seven countries, devised and directed by Dr. Ansel Keys, special cardiologist from Minnesota State, made Crete famous. He studied the health of people from 7 different countries; Holland, Finland, Japan, USA and of Mediterranean countries Italy, Yugoslavia and Greece. From Greece he studied Cretans and inhabitants of Corfu. From all the population groups studied, the groups of Italy and Yugoslavia presented lower mortality from cardiovascular diseases compared with the groups of North Europe and USA. However what astonished them were the results of Cretans; they presented the lowest rate of mortality, independently from the cause of death. The Research was continued in 1991. The Sector of Social Medicine of the University of Crete undertook the review of individuals that had taken part in the research 31 years previously, and found that the survival rate of the Cretan group was 50%, while in Finland there were no survivors.